From a44599827ceb9cae19f843e13675d59a8e0eccd1 Mon Sep 17 00:00:00 2001
From: Edmond <1571649+edmonddantes@users.noreply.github.com>
Date: Fri, 3 Jul 2026 16:12:58 +0000
Subject: [PATCH 1/2] =?UTF-8?q?feat:=20built-in=20hot-reload=20triggers=20?=
 =?UTF-8?q?=E2=80=94=20enableHotReload=20(watcher)=20+=20enableReloadOnSig?=
 =?UTF-8?q?nal=20(SIGHUP)=20(#93)?=
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Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- HttpServerConfig::enableHotReload(watchPaths, extensions, debounceMs,
  maxHoldMs): the pool parent arms one recursive Async\FileSystemWatcher
  per path (engine-side debounce collapses change bursts); each delivered
  event invalidates the watched trees in opcache and rotates the pool via
  HttpServer::reload(). Config fields are parent-only, never snapshotted.
- HttpServerConfig::enableReloadOnSignal(): a persistent SIGHUP event armed
  for the whole pool run (no unarmed window between deliveries), each
  delivery is one rotation. Throws on Windows.
- Orchestrators are internal main-scope coroutines on the parent; teardown
  closes the watchers (ends their iterators) and notifies the signal waiter,
  which observes hot_reload_stopping and disposes its own event.
- Logged through the parent's http_log: reload.watch armed/failed,
  reload.signal armed, reload.trigger source=watcher|sighup.
- reload() now refuses under TRUE_ASYNC_SERVER_REACTOR_POOL=1: reactors
  route through worker inboxes registered for the pool's lifetime and there
  is no registry unregister yet — retiring workers under live reactors
  corrupted the heap (found by the new h3 test). Guard + test document the
  limit until inbox rotation lands (#80 follow-up).
- tests: 053 watcher e2e (file edit -> new code served, no manual reload),
  054 SIGHUP rotation, websocket/034 reload with a live WS connection
  (old conn retired, fresh cohort serves WS), h3/045 reactor-pool guard.
  Full sweep: 277 passed, 0 failed.
---
 include/php_http_server.h                     |   9 +
 src/http_server_class.c                       | 462 ++++++++++++++++++
 src/http_server_config.c                      | 120 +++++
 stubs/HttpServerConfig.php                    |  21 +
 stubs/HttpServerConfig.php_arginfo.h          |  17 +-
 .../server/core/053-hot-reload-watcher.phpt   |  77 +++
 .../server/core/054-hot-reload-sighup.phpt    |  79 +++
 .../server/h3/045-h3-reload-reactor-pool.phpt |  90 ++++
 tests/phpt/websocket/034-hot-reload-ws.phpt   | 146 ++++++
 9 files changed, 1020 insertions(+), 1 deletion(-)
 create mode 100644 tests/phpt/server/core/053-hot-reload-watcher.phpt
 create mode 100644 tests/phpt/server/core/054-hot-reload-sighup.phpt
 create mode 100644 tests/phpt/server/h3/045-h3-reload-reactor-pool.phpt
 create mode 100644 tests/phpt/websocket/034-hot-reload-ws.phpt

diff --git a/include/php_http_server.h b/include/php_http_server.h
index 512747c..ae39b59 100644
--- a/include/php_http_server.h
+++ b/include/php_http_server.h
@@ -307,6 +307,15 @@ struct _http_server_config_t {
     zval     log_stream;
     bool     telemetry_enabled;
 
+    /* Hot-reload triggers (issue #93) — consumed by the pool parent only
+     * (the orchestrator coroutines run there), never snapshotted.
+     * hot_reload_paths IS_UNDEF = watcher trigger off. */
+    zval     hot_reload_paths;       /* array of directories to watch */
+    zval     hot_reload_extensions;  /* array of extensions; empty = all */
+    uint32_t hot_reload_debounce_ms;
+    uint32_t hot_reload_max_hold_ms;
+    bool     reload_on_sighup;
+
     /* Frozen persistent snapshot — populated at lock time, shared refcounted
      * across threads. NULL until the owning HttpServer constructs (which calls
      * http_server_config_lock) or the Config is transferred directly via a
diff --git a/src/http_server_class.c b/src/http_server_class.c
index 867c689..52198f0 100644
--- a/src/http_server_class.c
+++ b/src/http_server_class.c
@@ -33,6 +33,10 @@
 #include "core/worker_registry.h"
 #include "core/response_wire.h"
 #include "log/http_log.h"
+#ifndef PHP_WIN32
+#include <dirent.h>
+#include <sys/stat.h>
+#endif
 #include "static/static_handler.h"
 #include "static/http_static_cache.h"
 #ifdef HAVE_HTTP_SERVER_HTTP3
@@ -479,6 +483,14 @@ struct http_server_object {
     bool                     reload_in_progress;/* parent: one rotation at a time */
     void                    *pool_await_state;  /* parent: st of the active pool run */
 
+    /* Hot-reload triggers (issue #93), pool parent only. Watcher objects are
+     * closed and released by http_server_hot_reload_down; the SIGHUP event is
+     * owned by its orchestrator coroutine (the pointer here only lets teardown
+     * wake it). */
+    zval                     hot_reload_watchers; /* array of Async\FileSystemWatcher */
+    void                    *sighup_event;        /* zend_async_signal_event_t* */
+    bool                     hot_reload_stopping; /* orchestrators must exit */
+
     /* Transit sidecar — non-NULL only in the persistent shell created by
      * transfer_obj(TRANSFER). Holds pemalloc-copied closures so the LOAD
      * side can rebuild fcall_t entries in the destination thread's heap.
@@ -576,6 +588,9 @@ typedef struct {
 } http_server_reload_shared_t;
 
 static void http_server_do_stop(http_server_object *server, const char *reason);
+static void http_server_hot_reload_up(http_server_object *server, zval *this_zv,
+                                      http_server_config_t *cfg);
+static void http_server_hot_reload_down(http_server_object *server);
 
 /* Runs on a fresh coroutine enqueued by the deadline tick: stop() disposes that
  * very tick timer, which must not happen from inside its own callback. */
@@ -2710,6 +2725,12 @@ static int http_server_start_pool(http_server_object *server,
     server->in_pool_mode = true;
     server->running = true;
 
+    /* Arm hot-reload triggers (issue #93) on the parent before it suspends. */
+    if (boot_cfg != NULL
+        && (Z_TYPE(boot_cfg->hot_reload_paths) == IS_ARRAY || boot_cfg->reload_on_sighup)) {
+        http_server_hot_reload_up(server, this_zv, boot_cfg);
+    }
+
     /* Suspend until all submitted workers report done. Skip the suspend
      * entirely when nothing got submitted — there is no callback to
      * notify all_done, so awaiting on it would deadlock. */
@@ -2741,6 +2762,9 @@ static int http_server_start_pool(http_server_object *server,
     server->worker_pool = NULL;
     server->pool_await_state = NULL;
 
+    /* Retire the hot-reload orchestrators before the pool machinery goes. */
+    http_server_hot_reload_down(server);
+
     /* Workers have quiesced (the suspend returned). Tear down the transport
      * reactor pool: this releases the H3 listeners the gated reactors own,
      * frees the worker registry, and stops the reactor loops. */
@@ -3630,6 +3654,17 @@ ZEND_METHOD(TrueAsync_HttpServer, reload)
         RETURN_THROWS();
     }
 
+    /* The gated transport reactor pool (#80) routes requests through worker
+     * inboxes registered for the pool's lifetime; retiring a worker while the
+     * reactors are live would leave them posting into freed inboxes (there is
+     * no registry unregister yet). Refuse loudly instead of corrupting. */
+    if (UNEXPECTED(http_server_reactor_pool_enabled())) {
+        zend_throw_exception(http_server_runtime_exception_ce,
+            "reload() is not yet supported with TRUE_ASYNC_SERVER_REACTOR_POOL=1 "
+            "(worker inbox rotation is not implemented, #93)", 0);
+        RETURN_THROWS();
+    }
+
     if (server->reload_in_progress) {
         RETURN_FALSE; /* one rotation at a time — call again after it returns */
     }
@@ -3743,6 +3778,433 @@ ZEND_METHOD(TrueAsync_HttpServer, reload)
 }
 /* }}} */
 
+/* ==========================================================================
+ * Hot-reload triggers (issue #93) — pool-parent orchestrators.
+ * ========================================================================== */
+
+typedef struct {
+    zend_object *server_obj;   /* addref'd parent HttpServer */
+    zval         watcher;      /* owned Async\FileSystemWatcher */
+} hot_reload_watch_ctx_t;
+
+typedef struct {
+    zend_object *server_obj;
+} hot_reload_sighup_ctx_t;
+
+static void hot_reload_watch_ctx_dispose(zend_coroutine_t *co)
+{
+    hot_reload_watch_ctx_t *ctx = co->extended_data;
+
+    if (ctx == NULL) {
+        return;
+    }
+
+    co->extended_data = NULL;
+    zval_ptr_dtor(&ctx->watcher);
+    OBJ_RELEASE(ctx->server_obj);
+    efree(ctx);
+}
+
+static void hot_reload_sighup_ctx_dispose(zend_coroutine_t *co)
+{
+    hot_reload_sighup_ctx_t *ctx = co->extended_data;
+
+    if (ctx == NULL) {
+        return;
+    }
+
+    co->extended_data = NULL;
+    OBJ_RELEASE(ctx->server_obj);
+    efree(ctx);
+}
+
+#ifndef PHP_WIN32
+/* Case-insensitive extension allow-list check; NULL/empty list = every file. */
+static bool hot_reload_ext_matches(const HashTable *exts, const char *name)
+{
+    if (exts == NULL || zend_hash_num_elements((HashTable *)exts) == 0) {
+        return true;
+    }
+
+    const char *dot = strrchr(name, '.');
+
+    if (dot == NULL || dot[1] == '\0') {
+        return false;
+    }
+
+    const zval *entry;
+    ZEND_HASH_FOREACH_VAL((HashTable *)exts, entry)
+    {
+        if (Z_TYPE_P(entry) != IS_STRING) {
+            continue;
+        }
+
+        const char *e = Z_STRVAL_P(entry);
+
+        if (e[0] == '.') {
+            e++;
+        }
+
+        if (strcasecmp(dot + 1, e) == 0) {
+            return true;
+        }
+    }
+    ZEND_HASH_FOREACH_END();
+
+    return false;
+}
+
+/* opcache_invalidate($file, true) for every matching file under `dir`.
+ * `fname` is the pre-resolved "opcache_invalidate" callable zval. */
+static void hot_reload_invalidate_tree(const char *dir, const HashTable *exts,
+                                       zval *fname, const int depth)
+{
+    if (depth > 16) {
+        return;
+    }
+
+    DIR *d = opendir(dir);
+
+    if (d == NULL) {
+        return;
+    }
+
+    const struct dirent *ent;
+
+    while ((ent = readdir(d)) != NULL) {
+        if (ent->d_name[0] == '.'
+            && (ent->d_name[1] == '\0' || (ent->d_name[1] == '.' && ent->d_name[2] == '\0'))) {
+            continue;
+        }
+
+        char full[MAXPATHLEN];
+
+        if ((size_t)snprintf(full, sizeof(full), "%s/%s", dir, ent->d_name) >= sizeof(full)) {
+            continue;
+        }
+
+        struct stat st;
+
+        if (lstat(full, &st) != 0) {
+            continue;
+        }
+
+        if (S_ISDIR(st.st_mode)) {
+            hot_reload_invalidate_tree(full, exts, fname, depth + 1);
+            continue;
+        }
+
+        if (!S_ISREG(st.st_mode) || !hot_reload_ext_matches(exts, ent->d_name)) {
+            continue;
+        }
+
+        zval rv, params[2];
+        ZVAL_UNDEF(&rv);
+        ZVAL_STRING(&params[0], full);
+        ZVAL_TRUE(&params[1]);
+        call_user_function(NULL, NULL, fname, &rv, 2, params);
+        zval_ptr_dtor(&params[0]);
+        zval_ptr_dtor(&rv);
+
+        if (EG(exception)) {
+            zend_clear_exception();
+        }
+    }
+
+    closedir(d);
+}
+#endif /* !PHP_WIN32 */
+
+/* One trigger firing: invalidate the watched trees in opcache (so replacement
+ * bootloaders recompile the changed files) and rotate via HttpServer::reload(). */
+static void http_server_hot_reload_fire(zend_object *server_obj, const char *trigger)
+{
+    http_server_object *server = http_server_from_obj(server_obj);
+
+    if (server->hot_reload_stopping || !server->in_pool_mode) {
+        return;
+    }
+
+    http_logf_info(&server->log_state, "reload.trigger source=%s", trigger);
+
+#ifndef PHP_WIN32
+    http_server_config_t *cfg = http_server_get_config(server);
+
+    if (cfg != NULL && Z_TYPE(cfg->hot_reload_paths) == IS_ARRAY) {
+        zval fname;
+        ZVAL_STRING(&fname, "opcache_invalidate");
+
+        if (zend_is_callable(&fname, 0, NULL)) {
+            const HashTable *exts = (Z_TYPE(cfg->hot_reload_extensions) == IS_ARRAY)
+                                  ? Z_ARRVAL(cfg->hot_reload_extensions) : NULL;
+            const zval *path;
+            ZEND_HASH_FOREACH_VAL(Z_ARRVAL(cfg->hot_reload_paths), path)
+            {
+                hot_reload_invalidate_tree(Z_STRVAL_P(path), exts, &fname, 0);
+            }
+            ZEND_HASH_FOREACH_END();
+        }
+
+        zval_ptr_dtor(&fname);
+    }
+#endif
+
+    zval rv;
+    ZVAL_UNDEF(&rv);
+    zend_call_method_with_0_params(server_obj, NULL, NULL, "reload", &rv);
+    zval_ptr_dtor(&rv);
+
+    if (EG(exception)) {
+        http_logf_info(&server->log_state, "reload.trigger source=%s failed", trigger);
+        zend_clear_exception();
+    }
+}
+
+/* Coroutine: drive one watcher's iterator; every delivered (debounced) event
+ * is one reload. Ends when the watcher is closed by teardown. */
+static void http_server_hot_reload_watch_entry(void)
+{
+    zend_coroutine_t *co = ZEND_ASYNC_CURRENT_COROUTINE;
+    hot_reload_watch_ctx_t *ctx = co->extended_data;
+    http_server_object *server = http_server_from_obj(ctx->server_obj);
+
+    zval iter;
+    ZVAL_UNDEF(&iter);
+    zend_call_method_with_0_params(Z_OBJ(ctx->watcher), NULL, NULL, "getIterator", &iter);
+
+    if (EG(exception) || Z_TYPE(iter) != IS_OBJECT) {
+        zend_clear_exception();
+        zval_ptr_dtor(&iter);
+        return;
+    }
+
+    zval rv;
+    ZVAL_UNDEF(&rv);
+    zend_call_method_with_0_params(Z_OBJ(iter), NULL, NULL, "rewind", &rv);
+    zval_ptr_dtor(&rv);
+
+    while (!EG(exception) && !server->hot_reload_stopping) {
+        zval valid;
+        ZVAL_UNDEF(&valid);
+        zend_call_method_with_0_params(Z_OBJ(iter), NULL, NULL, "valid", &valid);
+
+        const bool go = !EG(exception) && zend_is_true(&valid);
+        zval_ptr_dtor(&valid);
+
+        if (!go || server->hot_reload_stopping) {
+            break;
+        }
+
+        http_server_hot_reload_fire(ctx->server_obj, "watcher");
+
+        if (server->hot_reload_stopping) {
+            break;
+        }
+
+        ZVAL_UNDEF(&rv);
+        zend_call_method_with_0_params(Z_OBJ(iter), NULL, NULL, "next", &rv);
+        zval_ptr_dtor(&rv);
+    }
+
+    if (EG(exception)) {
+        zend_clear_exception();
+    }
+
+    zval_ptr_dtor(&iter);
+}
+
+#ifndef PHP_WIN32
+/* Coroutine: persistent SIGHUP handler — one signal event armed for the whole
+ * pool run (no unarmed window), each delivery is one reload. */
+static void http_server_hot_reload_sighup_entry(void)
+{
+    zend_coroutine_t *co = ZEND_ASYNC_CURRENT_COROUTINE;
+    hot_reload_sighup_ctx_t *ctx = co->extended_data;
+    http_server_object *server = http_server_from_obj(ctx->server_obj);
+
+    zend_async_signal_event_t *sig = ZEND_ASYNC_NEW_SIGNAL_EVENT(SIGHUP);
+
+    if (UNEXPECTED(sig == NULL)) {
+        zend_clear_exception();
+        return;
+    }
+
+    if (UNEXPECTED(!sig->base.start(&sig->base))) {
+        zend_clear_exception();
+        sig->base.dispose(&sig->base);
+        return;
+    }
+
+    server->sighup_event = sig;
+    http_logf_info(&server->log_state, "reload.signal armed signal=SIGHUP");
+
+    while (!server->hot_reload_stopping) {
+        zend_async_resume_when(co, &sig->base, false, zend_async_waker_callback_resolve, NULL);
+        ZEND_ASYNC_SUSPEND();
+        ZEND_ASYNC_WAKER_DESTROY(co);
+
+        if (EG(exception)) {
+            zend_clear_exception();
+            break;
+        }
+
+        if (server->hot_reload_stopping) {
+            break;
+        }
+
+        http_server_hot_reload_fire(ctx->server_obj, "sighup");
+    }
+
+    server->sighup_event = NULL;
+    sig->base.stop(&sig->base);
+    sig->base.dispose(&sig->base);
+}
+#endif /* !PHP_WIN32 */
+
+/* Arm the configured triggers on the pool parent (called from start_pool just
+ * before it suspends). Failures degrade to "trigger off" with a log line. */
+static void http_server_hot_reload_up(http_server_object *server, zval *this_zv,
+                                      http_server_config_t *cfg)
+{
+    server->hot_reload_stopping = false;
+
+    if (Z_TYPE(cfg->hot_reload_paths) == IS_ARRAY) {
+        zend_string *cls = zend_string_init("Async\\FileSystemWatcher",
+                                            sizeof("Async\\FileSystemWatcher") - 1, 0);
+        zend_class_entry *ce = zend_lookup_class(cls);
+        zend_string_release(cls);
+
+        if (UNEXPECTED(ce == NULL)) {
+            zend_clear_exception();
+            http_logf_info(&server->log_state,
+                           "reload.watch unavailable (Async\\FileSystemWatcher missing)");
+            return;
+        }
+
+        array_init(&server->hot_reload_watchers);
+
+        const zval *path;
+        ZEND_HASH_FOREACH_VAL(Z_ARRVAL(cfg->hot_reload_paths), path)
+        {
+            zval watcher;
+
+            if (object_init_ex(&watcher, ce) != SUCCESS) {
+                zend_clear_exception();
+                continue;
+            }
+
+            zval args[6], rv;
+            ZVAL_COPY(&args[0], path);
+            ZVAL_TRUE(&args[1]);                                /* recursive */
+            ZVAL_TRUE(&args[2]);                                /* coalesce  */
+            ZVAL_LONG(&args[3], cfg->hot_reload_debounce_ms);
+            ZVAL_LONG(&args[4], cfg->hot_reload_max_hold_ms);
+
+            if (Z_TYPE(cfg->hot_reload_extensions) == IS_ARRAY) {
+                ZVAL_COPY(&args[5], &cfg->hot_reload_extensions);
+            } else {
+                array_init(&args[5]);
+            }
+
+            ZVAL_UNDEF(&rv);
+            zend_call_known_function(ce->constructor, Z_OBJ(watcher), ce, &rv,
+                                     6, args, NULL);
+            zval_ptr_dtor(&rv);
+            zval_ptr_dtor(&args[0]);
+            zval_ptr_dtor(&args[5]);
+
+            if (EG(exception)) {
+                http_logf_info(&server->log_state, "reload.watch failed path=%s",
+                               Z_STRVAL_P(path));
+                zend_clear_exception();
+                zval_ptr_dtor(&watcher);
+                continue;
+            }
+
+            hot_reload_watch_ctx_t *wctx = emalloc(sizeof(*wctx));
+            wctx->server_obj = Z_OBJ_P(this_zv);
+            GC_ADDREF(wctx->server_obj);
+            ZVAL_COPY(&wctx->watcher, &watcher);
+
+            zend_coroutine_t *co = ZEND_ASYNC_NEW_COROUTINE(ZEND_ASYNC_MAIN_SCOPE);
+
+            if (UNEXPECTED(co == NULL)) {
+                zend_clear_exception();
+                zval_ptr_dtor(&wctx->watcher);
+                OBJ_RELEASE(wctx->server_obj);
+                efree(wctx);
+                zval_ptr_dtor(&watcher);
+                continue;
+            }
+
+            co->internal_entry   = http_server_hot_reload_watch_entry;
+            co->extended_data    = wctx;
+            co->extended_dispose = hot_reload_watch_ctx_dispose;
+            ZEND_ASYNC_ENQUEUE_COROUTINE(co);
+
+            add_next_index_zval(&server->hot_reload_watchers, &watcher);
+            http_logf_info(&server->log_state,
+                           "reload.watch armed path=%s debounce_ms=%u max_hold_ms=%u",
+                           Z_STRVAL_P(path), cfg->hot_reload_debounce_ms,
+                           cfg->hot_reload_max_hold_ms);
+        }
+        ZEND_HASH_FOREACH_END();
+    }
+
+#ifndef PHP_WIN32
+    if (cfg->reload_on_sighup) {
+        hot_reload_sighup_ctx_t *sctx = emalloc(sizeof(*sctx));
+        sctx->server_obj = Z_OBJ_P(this_zv);
+        GC_ADDREF(sctx->server_obj);
+
+        zend_coroutine_t *co = ZEND_ASYNC_NEW_COROUTINE(ZEND_ASYNC_MAIN_SCOPE);
+
+        if (UNEXPECTED(co == NULL)) {
+            zend_clear_exception();
+            OBJ_RELEASE(sctx->server_obj);
+            efree(sctx);
+            return;
+        }
+
+        co->internal_entry   = http_server_hot_reload_sighup_entry;
+        co->extended_data    = sctx;
+        co->extended_dispose = hot_reload_sighup_ctx_dispose;
+        ZEND_ASYNC_ENQUEUE_COROUTINE(co);
+    }
+#endif
+}
+
+/* Retire the triggers: closing a watcher ends its iterator (the orchestrator
+ * sees valid()=false); notifying the signal event wakes its waiter, which
+ * observes hot_reload_stopping and disposes the event itself. */
+static void http_server_hot_reload_down(http_server_object *server)
+{
+    server->hot_reload_stopping = true;
+
+    if (Z_TYPE(server->hot_reload_watchers) == IS_ARRAY) {
+        const zval *w;
+        ZEND_HASH_FOREACH_VAL(Z_ARRVAL(server->hot_reload_watchers), w)
+        {
+            zval rv;
+            ZVAL_UNDEF(&rv);
+            zend_call_method_with_0_params(Z_OBJ_P(w), NULL, NULL, "close", &rv);
+            zval_ptr_dtor(&rv);
+
+            if (EG(exception)) {
+                zend_clear_exception();
+            }
+        }
+        ZEND_HASH_FOREACH_END();
+
+        zval_ptr_dtor(&server->hot_reload_watchers);
+        ZVAL_UNDEF(&server->hot_reload_watchers);
+    }
+
+    if (server->sighup_event != NULL) {
+        ZEND_ASYNC_CALLBACKS_NOTIFY((zend_async_event_t *) server->sighup_event, NULL, NULL);
+    }
+}
+
 /* {{{ proto HttpServer::isRunning(): bool */
 ZEND_METHOD(TrueAsync_HttpServer, isRunning)
 {
diff --git a/src/http_server_config.c b/src/http_server_config.c
index c668667..15a1e5a 100644
--- a/src/http_server_config.c
+++ b/src/http_server_config.c
@@ -411,6 +411,11 @@ ZEND_METHOD(TrueAsync_HttpServerConfig, __construct)
     config->stream_write_buffer_bytes    = DEFAULT_STREAM_WRITE_BUFFER_BYTES;
     config->max_body_size                = DEFAULT_MAX_BODY_SIZE;
     config->h2_static_budget_max         = 0;  /* 0 = auto from memory_limit */
+    ZVAL_UNDEF(&config->hot_reload_paths);
+    ZVAL_UNDEF(&config->hot_reload_extensions);
+    config->hot_reload_debounce_ms       = 300;
+    config->hot_reload_max_hold_ms       = 2000;
+    config->reload_on_sighup             = false;
     config->http3_idle_timeout_ms        = DEFAULT_HTTP3_IDLE_TIMEOUT_MS;
     config->http3_stream_window_bytes    = DEFAULT_HTTP3_STREAM_WINDOW_BYTES;
     config->http3_max_concurrent_streams = DEFAULT_HTTP3_MAX_CONCURRENT_STREAMS;
@@ -727,6 +732,111 @@ ZEND_METHOD(TrueAsync_HttpServerConfig, getWorkers)
 }
 /* }}} */
 
+/* {{{ proto HttpServerConfig::enableHotReload(array $watchPaths, array $extensions = ['php'], int $debounceMs = 300, int $maxHoldMs = 2000): static
+ *
+ * Dev hot-reload trigger (issue #93), pool mode only. The pool parent spawns
+ * one recursive Async\FileSystemWatcher per path with the given debounce; a
+ * collapsed change event invalidates the watched trees in opcache and calls
+ * HttpServer::reload() — replacement workers re-run the bootloader. */
+ZEND_METHOD(TrueAsync_HttpServerConfig, enableHotReload)
+{
+    HashTable *paths;
+    HashTable *extensions = NULL;
+    zend_long debounce_ms = 300;
+    zend_long max_hold_ms = 2000;
+
+    ZEND_PARSE_PARAMETERS_START(1, 4)
+        Z_PARAM_ARRAY_HT(paths)
+        Z_PARAM_OPTIONAL
+        Z_PARAM_ARRAY_HT(extensions)
+        Z_PARAM_LONG(debounce_ms)
+        Z_PARAM_LONG(max_hold_ms)
+    ZEND_PARSE_PARAMETERS_END();
+
+    http_server_config_t *config = Z_HTTP_SERVER_CONFIG_P(ZEND_THIS);
+
+    if (config_check_locked(config)) {
+        return;
+    }
+
+    if (zend_hash_num_elements(paths) == 0) {
+        zend_throw_exception(http_server_invalid_argument_exception_ce,
+            "enableHotReload() requires at least one watch path", 0);
+        return;
+    }
+
+    const zval *entry;
+    ZEND_HASH_FOREACH_VAL(paths, entry)
+    {
+        if (Z_TYPE_P(entry) != IS_STRING || Z_STRLEN_P(entry) == 0) {
+            zend_throw_exception(http_server_invalid_argument_exception_ce,
+                "enableHotReload() watch paths must be non-empty strings", 0);
+            return;
+        }
+    }
+    ZEND_HASH_FOREACH_END();
+
+    if (debounce_ms < 1 || debounce_ms > 600000 || max_hold_ms < 0 || max_hold_ms > 600000) {
+        zend_throw_exception(http_server_invalid_argument_exception_ce,
+            "enableHotReload() debounceMs must be 1..600000, maxHoldMs 0..600000", 0);
+        return;
+    }
+
+    if (Z_TYPE(config->hot_reload_paths) != IS_UNDEF) {
+        zval_ptr_dtor(&config->hot_reload_paths);
+    }
+
+    if (Z_TYPE(config->hot_reload_extensions) != IS_UNDEF) {
+        zval_ptr_dtor(&config->hot_reload_extensions);
+        ZVAL_UNDEF(&config->hot_reload_extensions);
+    }
+
+    ZVAL_ARR(&config->hot_reload_paths, zend_array_dup(paths));
+
+    if (extensions != NULL && zend_hash_num_elements(extensions) > 0) {
+        ZVAL_ARR(&config->hot_reload_extensions, zend_array_dup(extensions));
+    }
+
+    config->hot_reload_debounce_ms = (uint32_t)debounce_ms;
+    config->hot_reload_max_hold_ms = (uint32_t)max_hold_ms;
+
+    RETURN_OBJ_COPY(Z_OBJ_P(ZEND_THIS));
+}
+/* }}} */
+
+/* {{{ proto HttpServerConfig::enableReloadOnSignal(bool $enabled = true): static
+ *
+ * Prod hot-reload trigger (issue #93), pool mode only: the pool parent arms a
+ * persistent SIGHUP handler that calls HttpServer::reload(). */
+ZEND_METHOD(TrueAsync_HttpServerConfig, enableReloadOnSignal)
+{
+    bool enabled = true;
+
+    ZEND_PARSE_PARAMETERS_START(0, 1)
+        Z_PARAM_OPTIONAL
+        Z_PARAM_BOOL(enabled)
+    ZEND_PARSE_PARAMETERS_END();
+
+    http_server_config_t *config = Z_HTTP_SERVER_CONFIG_P(ZEND_THIS);
+
+    if (config_check_locked(config)) {
+        return;
+    }
+
+#ifdef PHP_WIN32
+    if (enabled) {
+        zend_throw_exception(http_server_invalid_argument_exception_ce,
+            "enableReloadOnSignal() is not supported on Windows (no SIGHUP)", 0);
+        return;
+    }
+#endif
+
+    config->reload_on_sighup = enabled;
+
+    RETURN_OBJ_COPY(Z_OBJ_P(ZEND_THIS));
+}
+/* }}} */
+
 /* {{{ proto HttpServerConfig::setBootloader(?Closure $bootloader): static
  *
  * Optional bootloader Closure handed to the built-in worker pool. The
@@ -2802,6 +2912,16 @@ static void http_server_config_free(zend_object *obj)
         ZVAL_UNDEF(&config->log_stream);
     }
 
+    if (Z_TYPE(config->hot_reload_paths) != IS_UNDEF) {
+        zval_ptr_dtor(&config->hot_reload_paths);
+        ZVAL_UNDEF(&config->hot_reload_paths);
+    }
+
+    if (Z_TYPE(config->hot_reload_extensions) != IS_UNDEF) {
+        zval_ptr_dtor(&config->hot_reload_extensions);
+        ZVAL_UNDEF(&config->hot_reload_extensions);
+    }
+
     if (Z_TYPE(config->bootloader) != IS_UNDEF) {
         zval_ptr_dtor(&config->bootloader);
         ZVAL_UNDEF(&config->bootloader);
diff --git a/stubs/HttpServerConfig.php b/stubs/HttpServerConfig.php
index 5b0695d..2a960a5 100644
--- a/stubs/HttpServerConfig.php
+++ b/stubs/HttpServerConfig.php
@@ -138,6 +138,27 @@ public function getWorkers(): int {}
      */
     public function setBootloader(?\Closure $bootloader): static {}
 
+    /**
+     * Dev hot-reload trigger (issue #93), pool mode only ({@see setWorkers()} > 1).
+     * The pool parent watches each path recursively (with the given debounce);
+     * a collapsed change event invalidates the watched trees in opcache and
+     * calls {@see HttpServer::reload()} — replacement workers re-run the
+     * bootloader with the changed code, on the same listen sockets.
+     *
+     * @param array $watchPaths Directories to watch (recursively).
+     * @param array $extensions Case-insensitive extension allow-list; empty = every file.
+     * @param int $debounceMs Quiet window before a burst of changes fires one reload.
+     * @param int $maxHoldMs Force a reload at most this long after the first change (0 = no cap).
+     */
+    public function enableHotReload(array $watchPaths, array $extensions = ['php'], int $debounceMs = 300, int $maxHoldMs = 2000): static {}
+
+    /**
+     * Prod hot-reload trigger (issue #93), pool mode only: the pool parent arms
+     * a persistent SIGHUP handler that calls {@see HttpServer::reload()}.
+     * Not supported on Windows.
+     */
+    public function enableReloadOnSignal(bool $enabled = true): static {}
+
     /**
      * Returns the bootloader previously set, or null.
      */
diff --git a/stubs/HttpServerConfig.php_arginfo.h b/stubs/HttpServerConfig.php_arginfo.h
index 4280a97..b7d2f86 100644
--- a/stubs/HttpServerConfig.php_arginfo.h
+++ b/stubs/HttpServerConfig.php_arginfo.h
@@ -1,5 +1,5 @@
 /* This is a generated file, edit HttpServerConfig.php.stub.php instead.
- * Stub hash: 3f74222f92482fa79cba17174f12fd9f023a317f */
+ * Stub hash: 4d389377f8768c3f1faf3593872627ba44c80676 */
 
 ZEND_BEGIN_ARG_INFO_EX(arginfo_class_TrueAsync_HttpServerConfig___construct, 0, 0, 0)
 	ZEND_ARG_TYPE_INFO_WITH_DEFAULT_VALUE(0, host, IS_STRING, 1, "null")
@@ -43,6 +43,17 @@ ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_class_TrueAsync_HttpServerConfig
 	ZEND_ARG_OBJ_INFO(0, bootloader, Closure, 1)
 ZEND_END_ARG_INFO()
 
+ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_class_TrueAsync_HttpServerConfig_enableHotReload, 0, 1, IS_STATIC, 0)
+	ZEND_ARG_TYPE_INFO(0, watchPaths, IS_ARRAY, 0)
+	ZEND_ARG_TYPE_INFO_WITH_DEFAULT_VALUE(0, extensions, IS_ARRAY, 0, "[\'php\']")
+	ZEND_ARG_TYPE_INFO_WITH_DEFAULT_VALUE(0, debounceMs, IS_LONG, 0, "300")
+	ZEND_ARG_TYPE_INFO_WITH_DEFAULT_VALUE(0, maxHoldMs, IS_LONG, 0, "2000")
+ZEND_END_ARG_INFO()
+
+ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_class_TrueAsync_HttpServerConfig_enableReloadOnSignal, 0, 0, IS_STATIC, 0)
+	ZEND_ARG_TYPE_INFO_WITH_DEFAULT_VALUE(0, enabled, _IS_BOOL, 0, "true")
+ZEND_END_ARG_INFO()
+
 ZEND_BEGIN_ARG_WITH_RETURN_OBJ_INFO_EX(arginfo_class_TrueAsync_HttpServerConfig_getBootloader, 0, 0, Closure, 1)
 ZEND_END_ARG_INFO()
 
@@ -289,6 +300,8 @@ ZEND_METHOD(TrueAsync_HttpServerConfig, setBacklog);
 ZEND_METHOD(TrueAsync_HttpServerConfig, setWorkers);
 ZEND_METHOD(TrueAsync_HttpServerConfig, getWorkers);
 ZEND_METHOD(TrueAsync_HttpServerConfig, setBootloader);
+ZEND_METHOD(TrueAsync_HttpServerConfig, enableHotReload);
+ZEND_METHOD(TrueAsync_HttpServerConfig, enableReloadOnSignal);
 ZEND_METHOD(TrueAsync_HttpServerConfig, getBootloader);
 ZEND_METHOD(TrueAsync_HttpServerConfig, getBacklog);
 ZEND_METHOD(TrueAsync_HttpServerConfig, setMaxConnections);
@@ -404,6 +417,8 @@ static const zend_function_entry class_TrueAsync_HttpServerConfig_methods[] = {
 	ZEND_ME(TrueAsync_HttpServerConfig, setWorkers, arginfo_class_TrueAsync_HttpServerConfig_setWorkers, ZEND_ACC_PUBLIC)
 	ZEND_ME(TrueAsync_HttpServerConfig, getWorkers, arginfo_class_TrueAsync_HttpServerConfig_getWorkers, ZEND_ACC_PUBLIC)
 	ZEND_ME(TrueAsync_HttpServerConfig, setBootloader, arginfo_class_TrueAsync_HttpServerConfig_setBootloader, ZEND_ACC_PUBLIC)
+	ZEND_ME(TrueAsync_HttpServerConfig, enableHotReload, arginfo_class_TrueAsync_HttpServerConfig_enableHotReload, ZEND_ACC_PUBLIC)
+	ZEND_ME(TrueAsync_HttpServerConfig, enableReloadOnSignal, arginfo_class_TrueAsync_HttpServerConfig_enableReloadOnSignal, ZEND_ACC_PUBLIC)
 	ZEND_ME(TrueAsync_HttpServerConfig, getBootloader, arginfo_class_TrueAsync_HttpServerConfig_getBootloader, ZEND_ACC_PUBLIC)
 	ZEND_ME(TrueAsync_HttpServerConfig, getBacklog, arginfo_class_TrueAsync_HttpServerConfig_getBacklog, ZEND_ACC_PUBLIC)
 	ZEND_ME(TrueAsync_HttpServerConfig, setMaxConnections, arginfo_class_TrueAsync_HttpServerConfig_setMaxConnections, ZEND_ACC_PUBLIC)
diff --git a/tests/phpt/server/core/053-hot-reload-watcher.phpt b/tests/phpt/server/core/053-hot-reload-watcher.phpt
new file mode 100644
index 0000000..701453f
--- /dev/null
+++ b/tests/phpt/server/core/053-hot-reload-watcher.phpt
@@ -0,0 +1,77 @@
+--TEST--
+HttpServerConfig::enableHotReload — file change triggers a pool rotation, new code served (#93)
+--EXTENSIONS--
+true_async_server
+true_async
+--SKIPIF--
+<?php
+if (PHP_OS_FAMILY === 'Windows') die('skip libuv on Windows lacks SO_REUSEPORT');
+if (!exec('curl --version 2>/dev/null')) die('skip curl CLI not available');
+?>
+--FILE--
+<?php
+/* The bootloader includes a watched PHP file for the app version. Rewriting
+ * that file must — with no manual reload() call — rotate the pool via the
+ * built-in watcher trigger and serve the new value on the same port. */
+
+use TrueAsync\HttpServer;
+use TrueAsync\HttpServerConfig;
+use function Async\spawn;
+
+require __DIR__ . '/../_free_port.inc';
+$port = tas_free_port();
+
+$dir  = sys_get_temp_dir() . '/tas_hotreload_' . getmypid();
+@mkdir($dir, 0777, true);
+$code = $dir . '/version.php';
+file_put_contents($code, "<?php return 'v1';");
+
+$config = (new HttpServerConfig())
+    ->addListener('127.0.0.1', $port)
+    ->setReadTimeout(5)
+    ->setWriteTimeout(5)
+    ->setWorkers(2)
+    ->setBootloader(static function () use ($code): void {
+        define('APP_V', (string) include $code);
+    })
+    ->enableHotReload([$dir], ['php'], 150, 1000);
+
+$server = new HttpServer($config);
+$server->addHttpHandler(function ($req, $res) {
+    $res->setStatusCode(200)->setBody(APP_V);
+});
+
+spawn(function () use ($port, $code, $dir) {
+    $curl = static fn (): string => (string) shell_exec(sprintf(
+        'curl -s --max-time 2 http://127.0.0.1:%d/ 2>/dev/null', $port));
+
+    $v1 = '';
+    for ($i = 0; $i < 50 && $v1 !== 'v1'; $i++) {
+        usleep(200000);
+        $v1 = $curl();
+    }
+
+    echo "before=", $v1, "\n";
+
+    /* The only action: rewrite the watched file. */
+    file_put_contents($code, "<?php return 'v2';");
+
+    $v2 = '';
+    for ($i = 0; $i < 100 && $v2 !== 'v2'; $i++) {
+        usleep(200000);
+        $v2 = $curl();
+    }
+
+    echo "after=", $v2, "\n";
+
+    @unlink($code);
+    @rmdir($dir);
+    posix_kill(getmypid(), SIGKILL);
+});
+
+$server->start();
+?>
+--EXPECTF--
+before=v1
+%A
+after=v2%A
diff --git a/tests/phpt/server/core/054-hot-reload-sighup.phpt b/tests/phpt/server/core/054-hot-reload-sighup.phpt
new file mode 100644
index 0000000..4625e06
--- /dev/null
+++ b/tests/phpt/server/core/054-hot-reload-sighup.phpt
@@ -0,0 +1,79 @@
+--TEST--
+HttpServerConfig::enableReloadOnSignal — SIGHUP rotates the pool, serving continues (#93)
+--EXTENSIONS--
+true_async_server
+true_async
+--SKIPIF--
+<?php
+if (PHP_OS_FAMILY === 'Windows') die('skip no SIGHUP on Windows');
+if (!exec('curl --version 2>/dev/null')) die('skip curl CLI not available');
+?>
+--FILE--
+<?php
+
+use TrueAsync\HttpServer;
+use TrueAsync\HttpServerConfig;
+use function Async\spawn;
+
+require __DIR__ . '/../_free_port.inc';
+$port  = tas_free_port();
+$bfile = sys_get_temp_dir() . '/tas_sighup_boot_' . getmypid();
+@unlink($bfile);
+
+$config = (new HttpServerConfig())
+    ->addListener('127.0.0.1', $port)
+    ->setReadTimeout(5)
+    ->setWriteTimeout(5)
+    ->setWorkers(2)
+    ->setBootloader(static function () use ($bfile): void {
+        file_put_contents($bfile, 'x', FILE_APPEND | LOCK_EX);
+    })
+    ->enableReloadOnSignal();
+
+$server = new HttpServer($config);
+$server->addHttpHandler(function ($req, $res) {
+    $res->setStatusCode(200)->setBody('pong');
+});
+
+spawn(function () use ($port, $bfile) {
+    $curl = static fn (): string => (string) shell_exec(sprintf(
+        'curl -s --max-time 2 http://127.0.0.1:%d/ 2>/dev/null', $port));
+
+    $up = '';
+    for ($i = 0; $i < 50 && $up !== 'pong'; $i++) {
+        usleep(200000);
+        $up = $curl();
+    }
+
+    echo "up=", $up, "\n";
+
+    posix_kill(getmypid(), SIGHUP);
+
+    /* Rotation done when both replacements have re-run the bootloader. */
+    $boots = 0;
+    for ($i = 0; $i < 100 && $boots < 4; $i++) {
+        usleep(200000);
+        $boots = strlen((string) @file_get_contents($bfile));
+    }
+
+    echo "boots=", $boots, "\n";
+
+    $again = '';
+    for ($i = 0; $i < 50 && $again !== 'pong'; $i++) {
+        usleep(200000);
+        $again = $curl();
+    }
+
+    echo "served_after=", $again, "\n";
+
+    @unlink($bfile);
+    posix_kill(getmypid(), SIGKILL);
+});
+
+$server->start();
+?>
+--EXPECTF--
+up=pong
+%A
+boots=4
+served_after=pong%A
diff --git a/tests/phpt/server/h3/045-h3-reload-reactor-pool.phpt b/tests/phpt/server/h3/045-h3-reload-reactor-pool.phpt
new file mode 100644
index 0000000..d9adfc5
--- /dev/null
+++ b/tests/phpt/server/h3/045-h3-reload-reactor-pool.phpt
@@ -0,0 +1,90 @@
+--TEST--
+HttpServer: reload() under the gated reactor pool is refused — inbox rotation not implemented (#93)
+--EXTENSIONS--
+true_async_server
+true_async
+--SKIPIF--
+<?php
+require __DIR__ . '/_h3_skipif.inc';
+if (PHP_OS_FAMILY === 'Windows') die('skip libuv on Windows lacks SO_REUSEPORT');
+h3_skipif(['openssl_cli' => true, 'h3client' => true]);
+?>
+--ENV--
+TRUE_ASYNC_SERVER_REACTOR_POOL=1
+PHP_HTTP3_DISABLE_RETRY=1
+--FILE--
+<?php
+/* Reactor-pool (#80) + hot reload (#93): the C transport reactors keep routing
+ * through worker inboxes registered for the pool's lifetime, and there is no
+ * registry unregister yet — retiring a worker under live reactors corrupts
+ * the heap (reactors post into freed inboxes). Until inbox rotation exists,
+ * reload() must refuse loudly, and H3 service must keep working afterwards. */
+
+use TrueAsync\HttpServer;
+use TrueAsync\HttpServerConfig;
+use function Async\spawn;
+
+require __DIR__ . '/_h3_skipif.inc';
+require __DIR__ . '/../_free_port.inc';
+
+$tmp = __DIR__ . '/tmp-045';
+@mkdir($tmp, 0700, true);
+$cert = $tmp . '/cert.pem';
+$key  = $tmp . '/key.pem';
+if (!h3_gen_cert($key, $cert)) { echo "cert gen failed\n"; exit(1); }
+register_shutdown_function(function () use ($tmp, $cert, $key) {
+    @unlink($cert); @unlink($key); @rmdir($tmp);
+});
+
+$port     = tas_free_port();
+$tcp_port = tas_free_port();
+
+$config = (new HttpServerConfig())
+    ->addListener('127.0.0.1', $tcp_port)   /* TCP listener required by start() */
+    ->addHttp3Listener('127.0.0.1', $port)
+    ->enableTls(true)->setCertificate($cert)->setPrivateKey($key)
+    ->setWorkers(2);
+$server = new HttpServer($config);
+$server->addHttpHandler(function ($req, $res) {
+    $res->setStatusCode(201)
+        ->setHeader('content-type', 'text/plain; charset=utf-8')
+        ->setBody('echo:' . $req->getMethod() . ':' . $req->getUri());
+});
+
+$client_bin = __DIR__ . '/../../../h3client/h3client';
+
+spawn(function () use ($server, $port, $client_bin) {
+    usleep(600000);   /* reactors + workers thread up and bind */
+
+    $get = static function (string $path) use ($client_bin, $port): string {
+        $cmd = sprintf('H3CLIENT_DEADLINE_MS=4000 %s 127.0.0.1 %d %s GET 2>&1',
+            escapeshellarg($client_bin), $port, $path);
+        $out = shell_exec($cmd) ?? '';
+        $status = preg_match('/^STATUS=(\d+)$/m', $out, $m) ? (int)$m[1] : -1;
+        $body = trim((string) preg_replace('/^STATUS=\d+\n?/m', '', $out));
+        return $status . ':' . $body;
+    };
+
+    echo "before=", $get('/one'), "\n";
+
+    try {
+        $server->reload();
+        echo "reload=no-throw\n";
+    } catch (\Throwable $e) {
+        echo "reload_refused=",
+            (int)(strpos($e->getMessage(), 'REACTOR_POOL') !== false), "\n";
+    }
+
+    /* The refusal must be side-effect free: H3 keeps serving. */
+    echo "after=", $get('/two'), "\n";
+
+    posix_kill(getmypid(), SIGKILL);
+});
+
+$server->start();
+?>
+--EXPECTF--
+%Abefore=201:echo:GET:/one
+reload_refused=1
+after=201:echo:GET:/two
+%A
diff --git a/tests/phpt/websocket/034-hot-reload-ws.phpt b/tests/phpt/websocket/034-hot-reload-ws.phpt
new file mode 100644
index 0000000..5a054e2
--- /dev/null
+++ b/tests/phpt/websocket/034-hot-reload-ws.phpt
@@ -0,0 +1,146 @@
+--TEST--
+WebSocket: pool reload with a live WS connection — old conn retired, fresh worker serves WS (#93)
+--EXTENSIONS--
+true_async_server
+true_async
+--SKIPIF--
+<?php
+if (PHP_OS_FAMILY === 'Windows') die('skip libuv on Windows lacks SO_REUSEPORT');
+?>
+--FILE--
+<?php
+/* A WS echo connection is open when HttpServer::reload() rotates the pool.
+ * The old worker's drain cancels the perpetual WS handler after the (short)
+ * grace window, the connection dies, the rotation completes, and a NEW WS
+ * connection to the same port echoes against the fresh cohort. */
+
+use TrueAsync\HttpServer;
+use TrueAsync\HttpServerConfig;
+use TrueAsync\WebSocket;
+use TrueAsync\HttpRequest;
+use function Async\spawn;
+
+require __DIR__ . '/../server/_free_port.inc';
+$port = tas_free_port();
+
+$config = (new HttpServerConfig())
+    ->addListener('127.0.0.1', $port)
+    ->setReadTimeout(5)
+    ->setWriteTimeout(5)
+    ->setShutdownTimeout(1)   /* keep the drain grace short for the rotation */
+    ->setWorkers(2);
+
+$server = new HttpServer($config);
+
+$server->addWebSocketHandler(function (WebSocket $ws, HttpRequest $req) {
+    while (($msg = $ws->recv()) !== null) {
+        $ws->send('echo: ' . $msg->data);
+    }
+});
+
+$server->addHttpHandler(function ($req, $resp) {
+    $resp->setStatusCode(404)->end();
+});
+
+function ws_client_text_frame(string $payload): string {
+    $mask = "abcd";
+    $masked = '';
+    for ($i = 0, $n = strlen($payload); $i < $n; $i++) {
+        $masked .= chr(ord($payload[$i]) ^ ord($mask[$i & 3]));
+    }
+    return chr(0x81) . chr(0x80 | strlen($payload)) . $mask . $masked;
+}
+
+function read_server_frame($fp): array {
+    $hdr = '';
+    while (strlen($hdr) < 2) {
+        $c = fread($fp, 2 - strlen($hdr));
+        if ($c === false || $c === '') return ['opcode' => -1, 'data' => ''];
+        $hdr .= $c;
+    }
+    $opcode = ord($hdr[0]) & 0x0f;
+    $len    = ord($hdr[1]) & 0x7f;
+    if ($len === 126) {
+        $extra = fread($fp, 2);
+        $len = (ord($extra[0]) << 8) | ord($extra[1]);
+    }
+    $data = '';
+    while (strlen($data) < $len) {
+        $c = fread($fp, $len - strlen($data));
+        if ($c === false || $c === '') break;
+        $data .= $c;
+    }
+    return ['opcode' => $opcode, 'data' => $data];
+}
+
+function ws_connect(int $port) {
+    $fp = @stream_socket_client("tcp://127.0.0.1:$port", $errno, $errstr, 2);
+    if ($fp === false) return false;
+    stream_set_timeout($fp, 5);
+    fwrite($fp,
+      "GET / HTTP/1.1\r\nHost: x\r\nUpgrade: websocket\r\nConnection: Upgrade\r\n"
+    . "Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==\r\nSec-WebSocket-Version: 13\r\n\r\n");
+    $hs = '';
+    while (!str_contains($hs, "\r\n\r\n")) {
+        $c = fread($fp, 4096);
+        if ($c === false || $c === '') return false;
+        $hs .= $c;
+    }
+    return str_contains($hs, ' 101 ') ? $fp : false;
+}
+
+spawn(function () use ($server, $port) {
+    usleep(400000);   /* let the pool come up */
+
+    /* Live WS connection on the old cohort. */
+    $fp = false;
+    for ($i = 0; $i < 25 && $fp === false; $i++) {
+        usleep(200000);
+        $fp = ws_connect($port);
+    }
+
+    if ($fp === false) {
+        echo "pre_ws=fail\n";
+        posix_kill(getmypid(), SIGKILL);
+    }
+
+    fwrite($fp, ws_client_text_frame('one'));
+    $r1 = read_server_frame($fp);
+    echo "pre_echo=", $r1['data'], "\n";
+
+    /* Rotate while the connection is open. */
+    $ok = $server->reload();
+    echo "reload=", var_export($ok, true), "\n";
+
+    /* The retired worker must end our connection: close frame (8) or EOF (-1). */
+    $r2 = read_server_frame($fp);
+    echo "old_conn_ended=", (int)($r2['opcode'] === 8 || $r2['opcode'] === -1), "\n";
+    fclose($fp);
+
+    /* Fresh cohort serves new WS connections on the same port. */
+    $fp2 = false;
+    for ($i = 0; $i < 50 && $fp2 === false; $i++) {
+        usleep(200000);
+        $fp2 = ws_connect($port);
+    }
+
+    if ($fp2 !== false) {
+        fwrite($fp2, ws_client_text_frame('two'));
+        $r3 = read_server_frame($fp2);
+        echo "post_echo=", $r3['data'], "\n";
+        fclose($fp2);
+    } else {
+        echo "post_echo=fail\n";
+    }
+
+    posix_kill(getmypid(), SIGKILL);
+});
+
+$server->start();
+?>
+--EXPECTF--
+pre_echo=echo: one
+%A
+reload=true
+old_conn_ended=1
+post_echo=echo: two%A

From 0f58b69b3334f0e8f98c237475c38f26dd4a8763 Mon Sep 17 00:00:00 2001
From: Edmond <1571649+edmonddantes@users.noreply.github.com>
Date: Fri, 3 Jul 2026 16:27:39 +0000
Subject: [PATCH 2/2] =?UTF-8?q?test:=20migrate=20every=20phpt=20to=20kerne?=
 =?UTF-8?q?l-allocated=20ports=20=E2=80=94=20kill=20the=20port-collision?=
 =?UTF-8?q?=20flake=20class=20(#93)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

206 tests used 'BASE + getmypid() % N' with massively overlapping ranges
(several %1000 spans, six tests sharing one literal base) while the server
binds with SO_REUSEPORT — so under run-tests -j any two concurrent tests
could silently share a port and split each other's traffic. That is the
mechanism behind the h2/012 flake fixed in #98 and the websocket/024
backpressure flake seen on this PR's first CI round (its base 19790+%100
sits in the middle of the crowd).

All 206 files now take tas_free_port(); tests that derive sibling ports
as $port+N use the new tas_free_port_span(N+1), which holds the whole
span before releasing it. Full suite at -j8, twice: 277 passed, 0 failed.
---
 tests/phpt/server/_free_port.inc              | 28 +++++++++++++++++++
 .../phpt/server/chaos/001-h2-rapid-reset.phpt |  3 +-
 .../chaos/002-h2-continuation-flood.phpt      |  3 +-
 .../compression/010-h1-buffered-gzip.phpt     |  3 +-
 .../compression/011-h1-buffered-skips.phpt    |  3 +-
 .../compression/012-h1-streaming-gzip.phpt    |  3 +-
 .../compression/020-h2-buffered-gzip.phpt     |  3 +-
 .../compression/030-h1-request-gzip-in.phpt   |  3 +-
 .../compression/040-h1-buffered-brotli.phpt   |  3 +-
 .../compression/041-h1-streaming-brotli.phpt  |  3 +-
 .../compression/050-h1-buffered-zstd.phpt     |  3 +-
 .../compression/060-h1-request-malformed.phpt |  3 +-
 .../compression/070-encoder-pool-reuse.phpt   |  3 +-
 .../server/core/004-server-start-stop.phpt    |  3 +-
 .../server/core/005-server-e2e-simple.phpt    |  3 +-
 .../007-server-transfer-handler-dispatch.phpt |  3 +-
 .../core/008-backpressure-telemetry.phpt      |  3 +-
 .../core/009-http-exception-from-handler.phpt |  4 ++-
 .../core/012-drain-telemetry-reset.phpt       |  3 +-
 .../core/014-log-emit-on-start-stop.phpt      |  4 ++-
 .../server/core/015-log-multipart-debug.phpt  |  4 ++-
 tests/phpt/server/core/016-log-tls-warn.phpt  |  4 ++-
 .../server/core/018-log-off-no-overhead.phpt  |  4 ++-
 .../server/core/019-parse-error-503-oom.phpt  |  3 +-
 .../server/core/020-builtin-worker-pool.phpt  |  4 ++-
 .../core/020-telemetry-trace-context.phpt     |  3 +-
 tests/phpt/server/core/021-bootloader.phpt    |  4 ++-
 .../server/core/021-response-headers-api.phpt |  3 +-
 .../server/core/022-response-status-api.phpt  |  3 +-
 .../server/core/023-response-body-api.phpt    |  3 +-
 .../server/core/024-response-helpers.phpt     |  3 +-
 .../server/core/025-response-state-api.phpt   |  3 +-
 .../core/026-response-trailers-api.phpt       |  3 +-
 .../server/core/027-response-validation.phpt  |  3 +-
 tests/phpt/server/core/030-response-json.phpt |  3 +-
 .../core/036-response-reason-phrases.phpt     |  4 ++-
 .../core/037-http-methods-end-to-end.phpt     |  4 ++-
 .../core/040-request-scope-isolation.phpt     |  3 +-
 .../041-current-context-child-coroutines.phpt |  3 +-
 .../phpt/server/core/042-request-context.phpt |  3 +-
 ...-request-context-equals-scope-context.phpt |  3 +-
 .../core/044-worker-pool-bound-handler.phpt   |  4 ++-
 .../server/core/045-request-context-h2.phpt   |  3 +-
 .../core/045-shutdown-drains-inflight.phpt    |  3 +-
 .../server/core/046-request-context-h3.phpt   |  3 +-
 .../core/047-request-context-concurrent.phpt  |  3 +-
 .../048-request-context-first-accessor.phpt   |  3 +-
 .../server/core/049-request-scope-setter.phpt |  3 +-
 .../core/050-request-scope-workers.phpt       |  3 +-
 tests/phpt/server/h1/001-pipelining.phpt      |  3 +-
 tests/phpt/server/h1/002-parse-error-414.phpt |  3 +-
 tests/phpt/server/h1/003-parse-error-431.phpt |  4 ++-
 tests/phpt/server/h1/004-parse-error-400.phpt |  4 ++-
 .../h1/005-parse-error-mid-stream-body.phpt   |  4 ++-
 tests/phpt/server/h1/006-smuggling-cl-te.phpt |  4 ++-
 .../phpt/server/h1/007-smuggling-dup-cl.phpt  |  4 ++-
 .../server/h1/008-invalid-content-length.phpt |  4 ++-
 .../phpt/server/h1/009-obs-fold-rejected.phpt |  4 ++-
 .../server/h1/010-drain-proactive-age-h1.phpt |  3 +-
 .../h1/011-drain-reactive-hardcap-h1.phpt     |  3 +-
 .../h1/012-drain-cooldown-blocks-refire.phpt  |  3 +-
 .../phpt/server/h1/013-h1-chunked-basic.phpt  |  3 +-
 tests/phpt/server/h1/014-h1-sse-pattern.phpt  |  3 +-
 .../server/h1/015-h1-stream-edge-cases.phpt   |  3 +-
 .../h1/016-h1-stream-after-send-many.phpt     |  3 +-
 .../server/h1/017-admission-reject-h1.phpt    |  3 +-
 .../phpt/server/h1/018-tcp-fragmentation.phpt |  3 +-
 tests/phpt/server/h1/019-host-validation.phpt |  4 ++-
 .../020-method-and-response-conformance.phpt  |  4 ++-
 .../h1/021-request-target-hardening.phpt      |  4 ++-
 tests/phpt/server/h1/022-h1-sse-api.phpt      |  3 +-
 .../phpt/server/h1/023-h1-sse-validation.phpt |  3 +-
 tests/phpt/server/h1/024-h1-sse-misuse.phpt   |  3 +-
 .../h1/025-h1-sse-client-disconnect.phpt      |  3 +-
 .../server/h1/050-stream-request-body.phpt    |  3 +-
 tests/phpt/server/h2/001-h2c-get.phpt         |  3 +-
 tests/phpt/server/h2/002-h2c-post.phpt        |  3 +-
 tests/phpt/server/h2/003-h2c-trailers.phpt    |  3 +-
 tests/phpt/server/h2/004-h2-tls-get.phpt      |  3 +-
 tests/phpt/server/h2/005-h2-tls-fallback.phpt |  3 +-
 tests/phpt/server/h2/006-h2c-multiplex.phpt   |  3 +-
 .../server/h2/007-h2c-peer-reset-cancel.phpt  |  3 +-
 .../h2/008-h2c-peer-reset-await-body.phpt     |  3 +-
 tests/phpt/server/h2/009-h2-h2spec-gate.phpt  |  4 +--
 .../h2/010-drain-proactive-age-h2-goaway.phpt |  3 +-
 .../h2/011-drain-h2-multiplex-completes.phpt  |  3 +-
 .../server/h2/013-h2-streaming-basic.phpt     |  3 +-
 .../server/h2/014-h2-streaming-large.phpt     |  3 +-
 .../h2/015-h2-streaming-backpressure.phpt     |  3 +-
 .../server/h2/016-h2-streaming-telemetry.phpt |  3 +-
 .../server/h2/017-h2-streaming-cancel.phpt    |  3 +-
 .../phpt/server/h2/018-h2-only-listener.phpt  |  3 +-
 .../server/h2/019-h2-stream-telemetry.phpt    |  3 +-
 .../server/h2/020-admission-reject-h2.phpt    |  3 +-
 .../phpt/server/h2/021-h2-tls-multiplex.phpt  |  4 ++-
 .../server/h2/022-h2-streaming-ring-full.phpt |  3 +-
 .../server/h2/023-h2-streaming-sendable.phpt  |  3 +-
 .../phpt/server/h2/024-h2-tls-large-body.phpt |  4 ++-
 tests/phpt/server/h2/025-h2-sse-api.phpt      |  3 +-
 .../server/h2/026-h2-sse-empty-start.phpt     |  3 +-
 .../server/h2/050-stream-request-body.phpt    |  3 +-
 tests/phpt/server/h3/001-h3-udp-recv.phpt     |  3 +-
 tests/phpt/server/h3/002-h3-packet-parse.phpt |  3 +-
 .../server/h3/004-h3-start-without-cert.phpt  |  3 +-
 .../h3/005-h3-repeat-initial-same-dcid.phpt   |  3 +-
 .../h3/008-h3-stats-handshake-keys.phpt       |  3 +-
 tests/phpt/server/h3/009-h3-e2e-get.phpt      |  3 +-
 .../server/h3/010-h3-e2e-post-await-body.phpt |  3 +-
 .../server/h3/011-h3-e2e-streaming-send.phpt  |  3 +-
 .../phpt/server/h3/012-h3-graceful-close.phpt |  3 +-
 .../server/h3/013-h3-stateless-reset.phpt     |  3 +-
 .../server/h3/014-h3-drain-max-conn-age.phpt  |  3 +-
 tests/phpt/server/h3/015-h3-idle-timeout.phpt |  3 +-
 .../server/h3/016-h3-per-peer-budget.phpt     |  3 +-
 .../phpt/server/h3/017-h3-alt-svc-header.phpt |  4 ++-
 .../server/h3/018-h3-version-negotiation.phpt |  3 +-
 .../h3/022-h3-stats-error-counters.phpt       |  3 +-
 .../server/h3/024-h3-config-setters-e2e.phpt  |  3 +-
 tests/phpt/server/h3/025-h3-retry-token.phpt  |  3 +-
 tests/phpt/server/h3/026-h3-static-file.phpt  |  3 +-
 tests/phpt/server/h3/027-h3-static-mount.phpt |  3 +-
 tests/phpt/server/h3/028-h3-large-body.phpt   |  4 +--
 .../phpt/server/h3/029-h3-pacing-setter.phpt  |  4 ++-
 .../031-h3-stats-nonzero-after-traffic.phpt   |  3 +-
 .../h3/032-h3-connection-migration.phpt       |  3 +-
 tests/phpt/server/h3/033-h3-head-request.phpt |  3 +-
 .../h3/034-h3-stateless-reset-clamps.phpt     |  3 +-
 .../h3/035-h3-request-body-overflow.phpt      |  3 +-
 .../server/h3/037-h3-reactor-pool-e2e.phpt    |  3 +-
 .../server/h3/038-h3-reactor-pool-post.phpt   |  3 +-
 .../server/h3/039-h3-reactor-pool-static.phpt |  3 +-
 .../h3/040-h3-reactor-pool-steering.phpt      |  3 +-
 .../h3/041-h3-migration-storm-guard.phpt      |  3 +-
 tests/phpt/server/h3/041-h3-sse-api.phpt      |  3 +-
 .../h3/042-h3-newcid-dcid-rotation.phpt       |  3 +-
 .../server/h3/042-h3-sse-empty-start.phpt     |  3 +-
 .../h3/043-h3-newcid-multi-rotation.phpt      |  3 +-
 tests/phpt/server/h3/044-hq-interop-file.phpt |  3 +-
 .../server/sendfile/001-sendfile-basic.phpt   |  4 ++-
 .../server/sendfile/002-sendfile-options.phpt |  4 ++-
 .../server/sendfile/003-sendfile-sealed.phpt  |  4 ++-
 .../server/sendfile/004-sendfile-errors.phpt  |  4 ++-
 .../server/sendfile/005-sendfile-rfc5987.phpt |  4 ++-
 .../phpt/server/static/001-static-basic.phpt  |  4 ++-
 .../002-static-dotfile-and-onmissing.phpt     |  4 ++-
 .../server/static/003-static-security.phpt    |  4 ++-
 .../server/static/004-static-workers.phpt     |  4 ++-
 .../static/005-static-if-modified-since.phpt  |  4 ++-
 .../006-static-zero-coroutine-counter.phpt    |  4 ++-
 .../static/007-static-tls-streaming.phpt      |  3 +-
 .../static/008-static-cache-counters.phpt     |  4 ++-
 .../static/009-static-symlink-owner.phpt      |  4 ++-
 .../static/010-static-precompressed.phpt      |  4 ++-
 .../011-static-precompressed-cache-uaf.phpt   |  4 ++-
 .../phpt/server/static/011-static-range.phpt  |  4 ++-
 tests/phpt/server/static/012-static-h2.phpt   |  4 ++-
 ...tic-precompressed-small-cache-headers.phpt |  4 ++-
 .../phpt/server/static/013-static-h2-tls.phpt |  3 +-
 .../server/static/014-static-body-cache.phpt  |  4 ++-
 .../static/015-static-ims-date-formats.phpt   |  4 ++-
 .../static/017-static-handler-locked.phpt     |  4 ++-
 .../static/018-static-hide-index-mime.phpt    |  4 ++-
 ...019-static-dotfile-ignore-and-noindex.phpt |  4 ++-
 .../020-static-extra-headers-and-mime.phpt    |  4 ++-
 .../021-static-symlink-reject-nofollow.phpt   |  4 ++-
 tests/phpt/server/tls/002-tls-config.phpt     |  4 +--
 tests/phpt/server/tls/003-tls-handshake.phpt  |  3 +-
 tests/phpt/server/tls/004-tls-get.phpt        |  3 +-
 tests/phpt/server/tls/005-tls-body.phpt       |  3 +-
 tests/phpt/server/tls/006-tls-keepalive.phpt  |  3 +-
 tests/phpt/server/tls/007-tls-pipelining.phpt |  3 +-
 tests/phpt/server/tls/008-tls-telemetry.phpt  |  3 +-
 tests/phpt/server/tls/009-tls-resumption.phpt |  3 +-
 tests/phpt/server/tls/010-tls-ktls.phpt       |  3 +-
 .../phpt/server/tls/011-tls-parse-error.phpt  |  3 +-
 .../server/tls/012-tls-security-level.phpt    |  4 ++-
 .../tls/013-tls-abrupt-and-plain-on-tls.phpt  |  3 +-
 .../tls/014-tls-h2-large-body-bio-park.phpt   |  4 ++-
 .../server/tls/015-tls-buffer-setter.phpt     |  4 ++-
 tests/phpt/websocket/005-handshake-101.phpt   |  3 +-
 tests/phpt/websocket/006-recv-text-frame.phpt |  3 +-
 tests/phpt/websocket/007-send-echo.phpt       |  3 +-
 tests/phpt/websocket/008-close-handshake.phpt |  3 +-
 tests/phpt/websocket/009-binary-frames.phpt   |  3 +-
 .../websocket/010-fragmented-message.phpt     |  3 +-
 tests/phpt/websocket/011-concurrent-recv.phpt |  3 +-
 tests/phpt/websocket/012-upgrade-reject.phpt  |  3 +-
 .../websocket/013-upgrade-subprotocol.phpt    |  3 +-
 tests/phpt/websocket/015-keepalive-ping.phpt  |  3 +-
 tests/phpt/websocket/016-auto-pong.phpt       |  3 +-
 tests/phpt/websocket/017-remote-address.phpt  |  3 +-
 tests/phpt/websocket/018-wss-echo.phpt        |  3 +-
 .../websocket/019-h2-extended-connect.phpt    |  3 +-
 .../020-permessage-deflate-echo.phpt          |  3 +-
 .../021-permessage-deflate-bomb.phpt          |  3 +-
 .../websocket/022-h2-permessage-deflate.phpt  |  3 +-
 .../websocket/023-backpressure-trysend.phpt   |  3 +-
 .../024-backpressure-send-blocks.phpt         |  3 +-
 .../025-spawned-writer-teardown.phpt          |  4 ++-
 .../websocket/026-pong-timeout-close.phpt     |  3 +-
 .../websocket/027-handshake-bad-version.phpt  |  3 +-
 .../websocket/028-handshake-missing-key.phpt  |  3 +-
 .../websocket/029-handshake-bad-method.phpt   |  3 +-
 .../websocket/030-utf8-failfast-teardown.phpt |  3 +-
 .../websocket/031-outbound-fragmentation.phpt |  3 +-
 .../websocket/032-closed-exception-code.phpt  |  3 +-
 .../phpt/websocket/033-foreach-iterator.phpt  |  3 +-
 207 files changed, 493 insertions(+), 209 deletions(-)

diff --git a/tests/phpt/server/_free_port.inc b/tests/phpt/server/_free_port.inc
index 0579fc9..b48f8dc 100644
--- a/tests/phpt/server/_free_port.inc
+++ b/tests/phpt/server/_free_port.inc
@@ -24,3 +24,31 @@ function tas_free_port(): int
 
     return (int) substr($name, strrpos($name, ':') + 1);
 }
+
+/* A base port P such that P..P+$count-1 are all bindable — for tests that
+ * derive sibling ports as $port + N (e.g. a TCP listener next to the H3 UDP
+ * one). Retries with fresh kernel-assigned bases until a whole span fits. */
+function tas_free_port_span(int $count): int
+{
+    for ($try = 0; $try < 32; $try++) {
+        $base = tas_free_port();
+        $held = [];
+        $ok = true;
+
+        for ($i = 0; $i < $count; $i++) {
+            $h = @stream_socket_server("tcp://127.0.0.1:" . ($base + $i), $e, $m);
+            if ($h === false) { $ok = false; break; }
+            $held[] = $h;
+        }
+
+        foreach ($held as $h) {
+            fclose($h);
+        }
+
+        if ($ok) {
+            return $base;
+        }
+    }
+
+    die('skip cannot allocate a free port span');
+}
diff --git a/tests/phpt/server/chaos/001-h2-rapid-reset.phpt b/tests/phpt/server/chaos/001-h2-rapid-reset.phpt
index 49f38d8..0ff5e53 100644
--- a/tests/phpt/server/chaos/001-h2-rapid-reset.phpt
+++ b/tests/phpt/server/chaos/001-h2-rapid-reset.phpt
@@ -26,8 +26,9 @@ use function Async\delay;
 
 require __DIR__ . '/../h2/_h2_client.inc';
 
-$port = 19870 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(10)
diff --git a/tests/phpt/server/chaos/002-h2-continuation-flood.phpt b/tests/phpt/server/chaos/002-h2-continuation-flood.phpt
index 2f402f7..e7edf3c 100644
--- a/tests/phpt/server/chaos/002-h2-continuation-flood.phpt
+++ b/tests/phpt/server/chaos/002-h2-continuation-flood.phpt
@@ -27,8 +27,9 @@ use function Async\delay;
 
 require __DIR__ . '/../h2/_h2_client.inc';
 
-$port = 19872 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(10)
diff --git a/tests/phpt/server/compression/010-h1-buffered-gzip.phpt b/tests/phpt/server/compression/010-h1-buffered-gzip.phpt
index 36e7322..01a7543 100644
--- a/tests/phpt/server/compression/010-h1-buffered-gzip.phpt
+++ b/tests/phpt/server/compression/010-h1-buffered-gzip.phpt
@@ -16,8 +16,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19200 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/compression/011-h1-buffered-skips.phpt b/tests/phpt/server/compression/011-h1-buffered-skips.phpt
index c5baae6..4a7ec4d 100644
--- a/tests/phpt/server/compression/011-h1-buffered-skips.phpt
+++ b/tests/phpt/server/compression/011-h1-buffered-skips.phpt
@@ -15,8 +15,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19250 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/compression/012-h1-streaming-gzip.phpt b/tests/phpt/server/compression/012-h1-streaming-gzip.phpt
index d4dfc8b..2fe8dba 100644
--- a/tests/phpt/server/compression/012-h1-streaming-gzip.phpt
+++ b/tests/phpt/server/compression/012-h1-streaming-gzip.phpt
@@ -16,8 +16,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19300 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/compression/020-h2-buffered-gzip.phpt b/tests/phpt/server/compression/020-h2-buffered-gzip.phpt
index 9f653e9..2edf48d 100644
--- a/tests/phpt/server/compression/020-h2-buffered-gzip.phpt
+++ b/tests/phpt/server/compression/020-h2-buffered-gzip.phpt
@@ -15,8 +15,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19350 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/compression/030-h1-request-gzip-in.phpt b/tests/phpt/server/compression/030-h1-request-gzip-in.phpt
index 51aea0f..da93377 100644
--- a/tests/phpt/server/compression/030-h1-request-gzip-in.phpt
+++ b/tests/phpt/server/compression/030-h1-request-gzip-in.phpt
@@ -16,8 +16,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19400 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/compression/040-h1-buffered-brotli.phpt b/tests/phpt/server/compression/040-h1-buffered-brotli.phpt
index 90e44bb..1f6cbef 100644
--- a/tests/phpt/server/compression/040-h1-buffered-brotli.phpt
+++ b/tests/phpt/server/compression/040-h1-buffered-brotli.phpt
@@ -18,8 +18,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19500 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/compression/041-h1-streaming-brotli.phpt b/tests/phpt/server/compression/041-h1-streaming-brotli.phpt
index 28d8dd7..7ba3d83 100644
--- a/tests/phpt/server/compression/041-h1-streaming-brotli.phpt
+++ b/tests/phpt/server/compression/041-h1-streaming-brotli.phpt
@@ -18,8 +18,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19700 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/compression/050-h1-buffered-zstd.phpt b/tests/phpt/server/compression/050-h1-buffered-zstd.phpt
index 185b7ba..98c9247 100644
--- a/tests/phpt/server/compression/050-h1-buffered-zstd.phpt
+++ b/tests/phpt/server/compression/050-h1-buffered-zstd.phpt
@@ -18,8 +18,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19600 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/compression/060-h1-request-malformed.phpt b/tests/phpt/server/compression/060-h1-request-malformed.phpt
index 9d154fd..e97fbcd 100644
--- a/tests/phpt/server/compression/060-h1-request-malformed.phpt
+++ b/tests/phpt/server/compression/060-h1-request-malformed.phpt
@@ -19,8 +19,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19800 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/compression/070-encoder-pool-reuse.phpt b/tests/phpt/server/compression/070-encoder-pool-reuse.phpt
index d6c5b7d..ba2009f 100644
--- a/tests/phpt/server/compression/070-encoder-pool-reuse.phpt
+++ b/tests/phpt/server/compression/070-encoder-pool-reuse.phpt
@@ -16,8 +16,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19300 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/core/004-server-start-stop.phpt b/tests/phpt/server/core/004-server-start-stop.phpt
index 4b90387..acd1cb1 100644
--- a/tests/phpt/server/core/004-server-start-stop.phpt
+++ b/tests/phpt/server/core/004-server-start-stop.phpt
@@ -9,8 +9,9 @@ use TrueAsync\HttpServer;
 use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 
-$port = 19900 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/core/005-server-e2e-simple.phpt b/tests/phpt/server/core/005-server-e2e-simple.phpt
index 459c6f4..04b28d0 100644
--- a/tests/phpt/server/core/005-server-e2e-simple.phpt
+++ b/tests/phpt/server/core/005-server-e2e-simple.phpt
@@ -10,8 +10,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19800 + getmypid() % 1000;  // Random-ish port to avoid conflicts
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/core/007-server-transfer-handler-dispatch.phpt b/tests/phpt/server/core/007-server-transfer-handler-dispatch.phpt
index f7d1f87..846f2aa 100644
--- a/tests/phpt/server/core/007-server-transfer-handler-dispatch.phpt
+++ b/tests/phpt/server/core/007-server-transfer-handler-dispatch.phpt
@@ -33,8 +33,9 @@ use Async\ThreadPool;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19840 + getmypid() % 50;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $coro = spawn(function () use ($port) {
     $config = (new HttpServerConfig())
         ->addListener('127.0.0.1', $port)
diff --git a/tests/phpt/server/core/008-backpressure-telemetry.phpt b/tests/phpt/server/core/008-backpressure-telemetry.phpt
index 4d6ef8c..795074f 100644
--- a/tests/phpt/server/core/008-backpressure-telemetry.phpt
+++ b/tests/phpt/server/core/008-backpressure-telemetry.phpt
@@ -10,8 +10,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19700 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/core/009-http-exception-from-handler.phpt b/tests/phpt/server/core/009-http-exception-from-handler.phpt
index f54c089..df0ac98 100644
--- a/tests/phpt/server/core/009-http-exception-from-handler.phpt
+++ b/tests/phpt/server/core/009-http-exception-from-handler.phpt
@@ -11,7 +11,9 @@ use TrueAsync\HttpException;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19820 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)->setWriteTimeout(5);
diff --git a/tests/phpt/server/core/012-drain-telemetry-reset.phpt b/tests/phpt/server/core/012-drain-telemetry-reset.phpt
index 1a0a417..e5fbf49 100644
--- a/tests/phpt/server/core/012-drain-telemetry-reset.phpt
+++ b/tests/phpt/server/core/012-drain-telemetry-reset.phpt
@@ -16,8 +16,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19845 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(10)
diff --git a/tests/phpt/server/core/014-log-emit-on-start-stop.phpt b/tests/phpt/server/core/014-log-emit-on-start-stop.phpt
index 6e05ff7..6718208 100644
--- a/tests/phpt/server/core/014-log-emit-on-start-stop.phpt
+++ b/tests/phpt/server/core/014-log-emit-on-start-stop.phpt
@@ -10,7 +10,9 @@ use TrueAsync\HttpServerConfig;
 use TrueAsync\LogSeverity;
 use function Async\spawn;
 
-$port = 19960 + getmypid() % 30;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port_span(2);
 $logfile = sys_get_temp_dir() . "/php-http-server-091-" . getmypid() . ".log";
 @unlink($logfile);
 $logfh = fopen($logfile, "w+b");
diff --git a/tests/phpt/server/core/015-log-multipart-debug.phpt b/tests/phpt/server/core/015-log-multipart-debug.phpt
index ebcea82..c94e6d4 100644
--- a/tests/phpt/server/core/015-log-multipart-debug.phpt
+++ b/tests/phpt/server/core/015-log-multipart-debug.phpt
@@ -11,7 +11,9 @@ use TrueAsync\LogSeverity;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19880 + getmypid() % 50;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port_span(2);
 $logfile = sys_get_temp_dir() . "/php-http-server-092-" . getmypid() . ".log";
 @unlink($logfile);
 $logfh = fopen($logfile, "w+b");
diff --git a/tests/phpt/server/core/016-log-tls-warn.phpt b/tests/phpt/server/core/016-log-tls-warn.phpt
index 8b45e28..e5f695e 100644
--- a/tests/phpt/server/core/016-log-tls-warn.phpt
+++ b/tests/phpt/server/core/016-log-tls-warn.phpt
@@ -23,7 +23,9 @@ $cert = $tmp . '/cert.pem';
 $key  = $tmp . '/key.pem';
 if (!tls_gen_cert($key, $cert)) { echo "cert generation failed\n"; exit(1); }
 
-$port = 19940 + getmypid() % 50;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $logfile = sys_get_temp_dir() . "/php-http-server-093-" . getmypid() . ".log";
 @unlink($logfile);
 $logfh = fopen($logfile, "w+b");
diff --git a/tests/phpt/server/core/018-log-off-no-overhead.phpt b/tests/phpt/server/core/018-log-off-no-overhead.phpt
index 218e385..87a1853 100644
--- a/tests/phpt/server/core/018-log-off-no-overhead.phpt
+++ b/tests/phpt/server/core/018-log-off-no-overhead.phpt
@@ -17,6 +17,8 @@ if (getenv('GITHUB_ACTIONS') !== false || getenv('SKIP_PERF_TESTS') !== false) {
 ?>
 --FILE--
 <?php
+require_once __DIR__ . '/../_free_port.inc';
+
 use TrueAsync\HttpServer;
 use TrueAsync\HttpServerConfig;
 use TrueAsync\LogSeverity;
@@ -46,7 +48,7 @@ function gen_body(string $boundary, int $fields): string {
 }
 
 function run(?int $severity_value, ?string $logfile): float {
-    $port = 19850 + getmypid() % 30 + ($severity_value ?? 0);
+    $port = tas_free_port();
     $cfg = (new HttpServerConfig())
         ->addListener('127.0.0.1', $port)
         ->setReadTimeout(5)
diff --git a/tests/phpt/server/core/019-parse-error-503-oom.phpt b/tests/phpt/server/core/019-parse-error-503-oom.phpt
index 2957f8a..bc903fc 100644
--- a/tests/phpt/server/core/019-parse-error-503-oom.phpt
+++ b/tests/phpt/server/core/019-parse-error-503-oom.phpt
@@ -22,8 +22,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19900 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setMaxBodySize(128 * 1024 * 1024)  /* allow big bodies in principle */
diff --git a/tests/phpt/server/core/020-builtin-worker-pool.phpt b/tests/phpt/server/core/020-builtin-worker-pool.phpt
index a5c8602..321064e 100644
--- a/tests/phpt/server/core/020-builtin-worker-pool.phpt
+++ b/tests/phpt/server/core/020-builtin-worker-pool.phpt
@@ -25,7 +25,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19880 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $workers = 2;
 
 $config = (new HttpServerConfig())
diff --git a/tests/phpt/server/core/020-telemetry-trace-context.phpt b/tests/phpt/server/core/020-telemetry-trace-context.phpt
index 3250f26..56a6a45 100644
--- a/tests/phpt/server/core/020-telemetry-trace-context.phpt
+++ b/tests/phpt/server/core/020-telemetry-trace-context.phpt
@@ -10,8 +10,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19770 + getmypid() % 50;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/core/021-bootloader.phpt b/tests/phpt/server/core/021-bootloader.phpt
index 2f10f1c..43e35b8 100644
--- a/tests/phpt/server/core/021-bootloader.phpt
+++ b/tests/phpt/server/core/021-bootloader.phpt
@@ -20,7 +20,9 @@ use TrueAsync\HttpServer;
 use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 
-$port    = 19980 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $workers = 2;
 
 $config = (new HttpServerConfig())
diff --git a/tests/phpt/server/core/021-response-headers-api.phpt b/tests/phpt/server/core/021-response-headers-api.phpt
index 0d27ce2..b5e432b 100644
--- a/tests/phpt/server/core/021-response-headers-api.phpt
+++ b/tests/phpt/server/core/021-response-headers-api.phpt
@@ -10,8 +10,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19200 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $server = new HttpServer((new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)->setWriteTimeout(5));
diff --git a/tests/phpt/server/core/022-response-status-api.phpt b/tests/phpt/server/core/022-response-status-api.phpt
index 50f014e..ad326e2 100644
--- a/tests/phpt/server/core/022-response-status-api.phpt
+++ b/tests/phpt/server/core/022-response-status-api.phpt
@@ -10,8 +10,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19210 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $server = new HttpServer((new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)->setWriteTimeout(5));
diff --git a/tests/phpt/server/core/023-response-body-api.phpt b/tests/phpt/server/core/023-response-body-api.phpt
index 2d48f75..56b9002 100644
--- a/tests/phpt/server/core/023-response-body-api.phpt
+++ b/tests/phpt/server/core/023-response-body-api.phpt
@@ -10,8 +10,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19220 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $server = new HttpServer((new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)->setWriteTimeout(5));
diff --git a/tests/phpt/server/core/024-response-helpers.phpt b/tests/phpt/server/core/024-response-helpers.phpt
index 031109d..753def7 100644
--- a/tests/phpt/server/core/024-response-helpers.phpt
+++ b/tests/phpt/server/core/024-response-helpers.phpt
@@ -13,8 +13,9 @@ use function Async\await;
 // One server, three requests against three different paths — each path
 // triggers a different helper. Server stops after the third response.
 
-$port = 19230 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $server = new HttpServer((new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)->setWriteTimeout(5));
diff --git a/tests/phpt/server/core/025-response-state-api.phpt b/tests/phpt/server/core/025-response-state-api.phpt
index e77f4cd..b58c3f1 100644
--- a/tests/phpt/server/core/025-response-state-api.phpt
+++ b/tests/phpt/server/core/025-response-state-api.phpt
@@ -10,8 +10,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19240 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $server = new HttpServer((new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)->setWriteTimeout(5));
diff --git a/tests/phpt/server/core/026-response-trailers-api.phpt b/tests/phpt/server/core/026-response-trailers-api.phpt
index 38ae4a3..64b65a5 100644
--- a/tests/phpt/server/core/026-response-trailers-api.phpt
+++ b/tests/phpt/server/core/026-response-trailers-api.phpt
@@ -14,8 +14,9 @@ use function Async\await;
 // drops trailers silently per the stub doc — no need for an H2 client
 // to verify the in-handler getters).
 
-$port = 19250 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $server = new HttpServer((new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)->setWriteTimeout(5));
diff --git a/tests/phpt/server/core/027-response-validation.phpt b/tests/phpt/server/core/027-response-validation.phpt
index b654d47..c3d2372 100644
--- a/tests/phpt/server/core/027-response-validation.phpt
+++ b/tests/phpt/server/core/027-response-validation.phpt
@@ -10,8 +10,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19260 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $server = new HttpServer((new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)->setWriteTimeout(5));
diff --git a/tests/phpt/server/core/030-response-json.phpt b/tests/phpt/server/core/030-response-json.phpt
index 3154f70..5cea3a6 100644
--- a/tests/phpt/server/core/030-response-json.phpt
+++ b/tests/phpt/server/core/030-response-json.phpt
@@ -15,8 +15,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19900 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/core/036-response-reason-phrases.phpt b/tests/phpt/server/core/036-response-reason-phrases.phpt
index 9313a18..95b96df 100644
--- a/tests/phpt/server/core/036-response-reason-phrases.phpt
+++ b/tests/phpt/server/core/036-response-reason-phrases.phpt
@@ -55,7 +55,9 @@ $codes = [
     299 => 'Unknown',
 ];
 
-$port = 19920 + getmypid() % 30;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 
diff --git a/tests/phpt/server/core/037-http-methods-end-to-end.phpt b/tests/phpt/server/core/037-http-methods-end-to-end.phpt
index 73b7e6d..0117674 100644
--- a/tests/phpt/server/core/037-http-methods-end-to-end.phpt
+++ b/tests/phpt/server/core/037-http-methods-end-to-end.phpt
@@ -15,7 +15,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port   = 20000 + getmypid() % 30;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 
diff --git a/tests/phpt/server/core/040-request-scope-isolation.phpt b/tests/phpt/server/core/040-request-scope-isolation.phpt
index 421f200..a0e3b3b 100644
--- a/tests/phpt/server/core/040-request-scope-isolation.phpt
+++ b/tests/phpt/server/core/040-request-scope-isolation.phpt
@@ -10,8 +10,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 20100 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/core/041-current-context-child-coroutines.phpt b/tests/phpt/server/core/041-current-context-child-coroutines.phpt
index ef4f1b9..03d429e 100644
--- a/tests/phpt/server/core/041-current-context-child-coroutines.phpt
+++ b/tests/phpt/server/core/041-current-context-child-coroutines.phpt
@@ -10,8 +10,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 20200 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/core/042-request-context.phpt b/tests/phpt/server/core/042-request-context.phpt
index dbdba66..f518b3b 100644
--- a/tests/phpt/server/core/042-request-context.phpt
+++ b/tests/phpt/server/core/042-request-context.phpt
@@ -10,8 +10,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 20300 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/core/043-request-context-equals-scope-context.phpt b/tests/phpt/server/core/043-request-context-equals-scope-context.phpt
index accf1b8..a198419 100644
--- a/tests/phpt/server/core/043-request-context-equals-scope-context.phpt
+++ b/tests/phpt/server/core/043-request-context-equals-scope-context.phpt
@@ -10,8 +10,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 20340 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/core/044-worker-pool-bound-handler.phpt b/tests/phpt/server/core/044-worker-pool-bound-handler.phpt
index 652cbf6..082fd6d 100644
--- a/tests/phpt/server/core/044-worker-pool-bound-handler.phpt
+++ b/tests/phpt/server/core/044-worker-pool-bound-handler.phpt
@@ -42,7 +42,9 @@ PHP;
 
 eval($handlerClassSrc);   // define BoundHandler in this (parent) thread
 
-$port    = 19840 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $workers = 2;
 
 $config = (new HttpServerConfig())
diff --git a/tests/phpt/server/core/045-request-context-h2.phpt b/tests/phpt/server/core/045-request-context-h2.phpt
index b49f14c..1ab2612 100644
--- a/tests/phpt/server/core/045-request-context-h2.phpt
+++ b/tests/phpt/server/core/045-request-context-h2.phpt
@@ -30,8 +30,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19790 + getmypid() % 60;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/core/045-shutdown-drains-inflight.phpt b/tests/phpt/server/core/045-shutdown-drains-inflight.phpt
index 0398f56..5a10cb4 100644
--- a/tests/phpt/server/core/045-shutdown-drains-inflight.phpt
+++ b/tests/phpt/server/core/045-shutdown-drains-inflight.phpt
@@ -15,8 +15,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 20180 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(10)
diff --git a/tests/phpt/server/core/046-request-context-h3.phpt b/tests/phpt/server/core/046-request-context-h3.phpt
index bca8f84..d098189 100644
--- a/tests/phpt/server/core/046-request-context-h3.phpt
+++ b/tests/phpt/server/core/046-request-context-h3.phpt
@@ -37,8 +37,9 @@ exec(sprintf('openssl req -x509 -newkey rsa:2048 -sha256 -days 1 -nodes '
     escapeshellarg($key), escapeshellarg($cert)), $_, $rc);
 if ($rc !== 0) { echo "cert gen failed\n"; exit(1); }
 
-$port = 20360 + getmypid() % 50;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/core/047-request-context-concurrent.phpt b/tests/phpt/server/core/047-request-context-concurrent.phpt
index 51822fe..ba1033e 100644
--- a/tests/phpt/server/core/047-request-context-concurrent.phpt
+++ b/tests/phpt/server/core/047-request-context-concurrent.phpt
@@ -26,8 +26,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 20120 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/core/048-request-context-first-accessor.phpt b/tests/phpt/server/core/048-request-context-first-accessor.phpt
index cf7629c..e9e31c0 100644
--- a/tests/phpt/server/core/048-request-context-first-accessor.phpt
+++ b/tests/phpt/server/core/048-request-context-first-accessor.phpt
@@ -10,8 +10,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 20340 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/core/049-request-scope-setter.phpt b/tests/phpt/server/core/049-request-scope-setter.phpt
index 3f20196..497b092 100644
--- a/tests/phpt/server/core/049-request-scope-setter.phpt
+++ b/tests/phpt/server/core/049-request-scope-setter.phpt
@@ -25,7 +25,8 @@ echo "set true  -> " . (int)$c->setRequestScope(true)->isRequestScope() . "\n";
 echo "chainable=" . (int)($c->setRequestScope(false) instanceof HttpServerConfig) . "\n"; /* 1 */
 
 /* === Part B: locked after the config is handed to a server === */
-$port = 19965 + getmypid() % 20;
+require_once __DIR__ . '/../_free_port.inc';
+$port = tas_free_port();
 $cfg = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setRequestScope(false)                /* serve with the per-request scope OFF */
diff --git a/tests/phpt/server/core/050-request-scope-workers.phpt b/tests/phpt/server/core/050-request-scope-workers.phpt
index 9ebb2bb..b8dfa82 100644
--- a/tests/phpt/server/core/050-request-scope-workers.phpt
+++ b/tests/phpt/server/core/050-request-scope-workers.phpt
@@ -23,8 +23,9 @@ use TrueAsync\HttpServer;
 use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 
-$port = 19985 + getmypid() % 20;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/h1/001-pipelining.phpt b/tests/phpt/server/h1/001-pipelining.phpt
index dd980e0..aa88f42 100644
--- a/tests/phpt/server/h1/001-pipelining.phpt
+++ b/tests/phpt/server/h1/001-pipelining.phpt
@@ -18,8 +18,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19650 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/h1/002-parse-error-414.phpt b/tests/phpt/server/h1/002-parse-error-414.phpt
index 7093083..3cedd88 100644
--- a/tests/phpt/server/h1/002-parse-error-414.phpt
+++ b/tests/phpt/server/h1/002-parse-error-414.phpt
@@ -10,8 +10,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19817 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/h1/003-parse-error-431.phpt b/tests/phpt/server/h1/003-parse-error-431.phpt
index 849a18c..d1e54e0 100644
--- a/tests/phpt/server/h1/003-parse-error-431.phpt
+++ b/tests/phpt/server/h1/003-parse-error-431.phpt
@@ -10,7 +10,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19818 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)->setReadTimeout(5)->setWriteTimeout(5);
 $server = new HttpServer($config);
diff --git a/tests/phpt/server/h1/004-parse-error-400.phpt b/tests/phpt/server/h1/004-parse-error-400.phpt
index 064373c..2682749 100644
--- a/tests/phpt/server/h1/004-parse-error-400.phpt
+++ b/tests/phpt/server/h1/004-parse-error-400.phpt
@@ -10,7 +10,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19819 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)->setReadTimeout(5)->setWriteTimeout(5);
 $server = new HttpServer($config);
diff --git a/tests/phpt/server/h1/005-parse-error-mid-stream-body.phpt b/tests/phpt/server/h1/005-parse-error-mid-stream-body.phpt
index 161c443..58852eb 100644
--- a/tests/phpt/server/h1/005-parse-error-mid-stream-body.phpt
+++ b/tests/phpt/server/h1/005-parse-error-mid-stream-body.phpt
@@ -10,7 +10,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19821 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(10)->setWriteTimeout(10);
diff --git a/tests/phpt/server/h1/006-smuggling-cl-te.phpt b/tests/phpt/server/h1/006-smuggling-cl-te.phpt
index 57cf406..5d17341 100644
--- a/tests/phpt/server/h1/006-smuggling-cl-te.phpt
+++ b/tests/phpt/server/h1/006-smuggling-cl-te.phpt
@@ -10,7 +10,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19822 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)->setReadTimeout(5)->setWriteTimeout(5);
 $server = new HttpServer($config);
diff --git a/tests/phpt/server/h1/007-smuggling-dup-cl.phpt b/tests/phpt/server/h1/007-smuggling-dup-cl.phpt
index efd8911..635e651 100644
--- a/tests/phpt/server/h1/007-smuggling-dup-cl.phpt
+++ b/tests/phpt/server/h1/007-smuggling-dup-cl.phpt
@@ -10,7 +10,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19823 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)->setReadTimeout(5)->setWriteTimeout(5);
 $server = new HttpServer($config);
diff --git a/tests/phpt/server/h1/008-invalid-content-length.phpt b/tests/phpt/server/h1/008-invalid-content-length.phpt
index 033f96a..6160a31 100644
--- a/tests/phpt/server/h1/008-invalid-content-length.phpt
+++ b/tests/phpt/server/h1/008-invalid-content-length.phpt
@@ -10,7 +10,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19824 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)->setReadTimeout(5)->setWriteTimeout(5);
 $server = new HttpServer($config);
diff --git a/tests/phpt/server/h1/009-obs-fold-rejected.phpt b/tests/phpt/server/h1/009-obs-fold-rejected.phpt
index 1f29cc1..92f5a9b 100644
--- a/tests/phpt/server/h1/009-obs-fold-rejected.phpt
+++ b/tests/phpt/server/h1/009-obs-fold-rejected.phpt
@@ -10,7 +10,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19825 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)->setReadTimeout(5)->setWriteTimeout(5);
 $server = new HttpServer($config);
diff --git a/tests/phpt/server/h1/010-drain-proactive-age-h1.phpt b/tests/phpt/server/h1/010-drain-proactive-age-h1.phpt
index 792ece8..e98d6d1 100644
--- a/tests/phpt/server/h1/010-drain-proactive-age-h1.phpt
+++ b/tests/phpt/server/h1/010-drain-proactive-age-h1.phpt
@@ -16,8 +16,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19840 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(10)
diff --git a/tests/phpt/server/h1/011-drain-reactive-hardcap-h1.phpt b/tests/phpt/server/h1/011-drain-reactive-hardcap-h1.phpt
index 4253017..06724ef 100644
--- a/tests/phpt/server/h1/011-drain-reactive-hardcap-h1.phpt
+++ b/tests/phpt/server/h1/011-drain-reactive-hardcap-h1.phpt
@@ -16,8 +16,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19841 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(10)
diff --git a/tests/phpt/server/h1/012-drain-cooldown-blocks-refire.phpt b/tests/phpt/server/h1/012-drain-cooldown-blocks-refire.phpt
index f55e0a4..2ff1fee 100644
--- a/tests/phpt/server/h1/012-drain-cooldown-blocks-refire.phpt
+++ b/tests/phpt/server/h1/012-drain-cooldown-blocks-refire.phpt
@@ -16,8 +16,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19846 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(10)
diff --git a/tests/phpt/server/h1/013-h1-chunked-basic.phpt b/tests/phpt/server/h1/013-h1-chunked-basic.phpt
index e2e00a3..c261d83 100644
--- a/tests/phpt/server/h1/013-h1-chunked-basic.phpt
+++ b/tests/phpt/server/h1/013-h1-chunked-basic.phpt
@@ -14,8 +14,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19820 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $server = new HttpServer(
     (new HttpServerConfig())
         ->addListener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h1/014-h1-sse-pattern.phpt b/tests/phpt/server/h1/014-h1-sse-pattern.phpt
index 305ac13..60e28ac 100644
--- a/tests/phpt/server/h1/014-h1-sse-pattern.phpt
+++ b/tests/phpt/server/h1/014-h1-sse-pattern.phpt
@@ -14,8 +14,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19840 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $server = new HttpServer(
     (new HttpServerConfig())
         ->addListener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h1/015-h1-stream-edge-cases.phpt b/tests/phpt/server/h1/015-h1-stream-edge-cases.phpt
index ac56ea1..cbc7a43 100644
--- a/tests/phpt/server/h1/015-h1-stream-edge-cases.phpt
+++ b/tests/phpt/server/h1/015-h1-stream-edge-cases.phpt
@@ -14,8 +14,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19340 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $server = new HttpServer((new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(10)->setWriteTimeout(10));
diff --git a/tests/phpt/server/h1/016-h1-stream-after-send-many.phpt b/tests/phpt/server/h1/016-h1-stream-after-send-many.phpt
index b945ed7..465b07f 100644
--- a/tests/phpt/server/h1/016-h1-stream-after-send-many.phpt
+++ b/tests/phpt/server/h1/016-h1-stream-after-send-many.phpt
@@ -14,8 +14,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19350 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $server = new HttpServer((new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(10)->setWriteTimeout(10));
diff --git a/tests/phpt/server/h1/017-admission-reject-h1.phpt b/tests/phpt/server/h1/017-admission-reject-h1.phpt
index a16599b..1d450eb 100644
--- a/tests/phpt/server/h1/017-admission-reject-h1.phpt
+++ b/tests/phpt/server/h1/017-admission-reject-h1.phpt
@@ -23,8 +23,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19910 + getmypid() % 80;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setMaxConnections(32)
diff --git a/tests/phpt/server/h1/018-tcp-fragmentation.phpt b/tests/phpt/server/h1/018-tcp-fragmentation.phpt
index 07b96ca..3bac072 100644
--- a/tests/phpt/server/h1/018-tcp-fragmentation.phpt
+++ b/tests/phpt/server/h1/018-tcp-fragmentation.phpt
@@ -24,8 +24,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19850 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/h1/019-host-validation.phpt b/tests/phpt/server/h1/019-host-validation.phpt
index 0a7c929..b0fbe31 100644
--- a/tests/phpt/server/h1/019-host-validation.phpt
+++ b/tests/phpt/server/h1/019-host-validation.phpt
@@ -22,7 +22,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19824 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)->setReadTimeout(5)->setWriteTimeout(5);
 $server = new HttpServer($config);
diff --git a/tests/phpt/server/h1/020-method-and-response-conformance.phpt b/tests/phpt/server/h1/020-method-and-response-conformance.phpt
index 4650b2c..a8f2c01 100644
--- a/tests/phpt/server/h1/020-method-and-response-conformance.phpt
+++ b/tests/phpt/server/h1/020-method-and-response-conformance.phpt
@@ -21,7 +21,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19825 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $server = new HttpServer((new HttpServerConfig())
     ->addListener('127.0.0.1', $port)->setReadTimeout(5)->setWriteTimeout(5));
 $server->addHttpHandler(function ($req, $res) {
diff --git a/tests/phpt/server/h1/021-request-target-hardening.phpt b/tests/phpt/server/h1/021-request-target-hardening.phpt
index 7793db3..4808d57 100644
--- a/tests/phpt/server/h1/021-request-target-hardening.phpt
+++ b/tests/phpt/server/h1/021-request-target-hardening.phpt
@@ -22,7 +22,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19826 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $server = new HttpServer((new HttpServerConfig())
     ->addListener('127.0.0.1', $port)->setReadTimeout(5)->setWriteTimeout(5));
 $server->addHttpHandler(function ($req, $res) {
diff --git a/tests/phpt/server/h1/022-h1-sse-api.phpt b/tests/phpt/server/h1/022-h1-sse-api.phpt
index c735100..92c0e73 100644
--- a/tests/phpt/server/h1/022-h1-sse-api.phpt
+++ b/tests/phpt/server/h1/022-h1-sse-api.phpt
@@ -24,8 +24,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19880 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $server = new HttpServer(
     (new HttpServerConfig())
         ->addListener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h1/023-h1-sse-validation.phpt b/tests/phpt/server/h1/023-h1-sse-validation.phpt
index 9c1e657..4e4f5fb 100644
--- a/tests/phpt/server/h1/023-h1-sse-validation.phpt
+++ b/tests/phpt/server/h1/023-h1-sse-validation.phpt
@@ -20,8 +20,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19680 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $server = new HttpServer(
     (new HttpServerConfig())
         ->addListener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h1/024-h1-sse-misuse.phpt b/tests/phpt/server/h1/024-h1-sse-misuse.phpt
index 88b946e..9f57e12 100644
--- a/tests/phpt/server/h1/024-h1-sse-misuse.phpt
+++ b/tests/phpt/server/h1/024-h1-sse-misuse.phpt
@@ -23,8 +23,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19700 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $server = new HttpServer(
     (new HttpServerConfig())
         ->addListener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h1/025-h1-sse-client-disconnect.phpt b/tests/phpt/server/h1/025-h1-sse-client-disconnect.phpt
index 83bd4c6..ab8f001 100644
--- a/tests/phpt/server/h1/025-h1-sse-client-disconnect.phpt
+++ b/tests/phpt/server/h1/025-h1-sse-client-disconnect.phpt
@@ -22,8 +22,9 @@ use TrueAsync\HttpException;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19780 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $server = new HttpServer(
     (new HttpServerConfig())
         ->addListener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h1/050-stream-request-body.phpt b/tests/phpt/server/h1/050-stream-request-body.phpt
index 1c4a0a3..fe95017 100644
--- a/tests/phpt/server/h1/050-stream-request-body.phpt
+++ b/tests/phpt/server/h1/050-stream-request-body.phpt
@@ -14,8 +14,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19920 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $server = new HttpServer(
     (new HttpServerConfig())
         ->addListener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h2/001-h2c-get.phpt b/tests/phpt/server/h2/001-h2c-get.phpt
index cc433a8..5b44e76 100644
--- a/tests/phpt/server/h2/001-h2c-get.phpt
+++ b/tests/phpt/server/h2/001-h2c-get.phpt
@@ -24,8 +24,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19700 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/h2/002-h2c-post.phpt b/tests/phpt/server/h2/002-h2c-post.phpt
index 4b3ec49..4d3aef1 100644
--- a/tests/phpt/server/h2/002-h2c-post.phpt
+++ b/tests/phpt/server/h2/002-h2c-post.phpt
@@ -21,8 +21,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19710 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/h2/003-h2c-trailers.phpt b/tests/phpt/server/h2/003-h2c-trailers.phpt
index f0db5cd..aadf7de 100644
--- a/tests/phpt/server/h2/003-h2c-trailers.phpt
+++ b/tests/phpt/server/h2/003-h2c-trailers.phpt
@@ -21,8 +21,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19720 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/h2/004-h2-tls-get.phpt b/tests/phpt/server/h2/004-h2-tls-get.phpt
index dbf5a6a..21fc9be 100644
--- a/tests/phpt/server/h2/004-h2-tls-get.phpt
+++ b/tests/phpt/server/h2/004-h2-tls-get.phpt
@@ -29,8 +29,9 @@ $cert = $tmp_dir . '/cert.pem';
 $key  = $tmp_dir . '/key.pem';
 if (!h2_gen_cert($key, $cert)) { echo "cert gen failed\n"; exit(1); }
 
-$port = 19970 + getmypid() % 20;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port, true)
     ->enableTls(true)
diff --git a/tests/phpt/server/h2/005-h2-tls-fallback.phpt b/tests/phpt/server/h2/005-h2-tls-fallback.phpt
index cf1b578..b2178bb 100644
--- a/tests/phpt/server/h2/005-h2-tls-fallback.phpt
+++ b/tests/phpt/server/h2/005-h2-tls-fallback.phpt
@@ -29,8 +29,9 @@ $cert = $tmp_dir . '/cert.pem';
 $key  = $tmp_dir . '/key.pem';
 if (!h2_gen_cert($key, $cert)) { echo "cert gen failed\n"; exit(1); }
 
-$port = 19990 + getmypid() % 9;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port, true)
     ->enableTls(true)
diff --git a/tests/phpt/server/h2/006-h2c-multiplex.phpt b/tests/phpt/server/h2/006-h2c-multiplex.phpt
index c3e49ca..2e11142 100644
--- a/tests/phpt/server/h2/006-h2c-multiplex.phpt
+++ b/tests/phpt/server/h2/006-h2c-multiplex.phpt
@@ -26,8 +26,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19730 + getmypid() % 60;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/server/h2/007-h2c-peer-reset-cancel.phpt b/tests/phpt/server/h2/007-h2c-peer-reset-cancel.phpt
index f6e99e9..36e21aa 100644
--- a/tests/phpt/server/h2/007-h2c-peer-reset-cancel.phpt
+++ b/tests/phpt/server/h2/007-h2c-peer-reset-cancel.phpt
@@ -31,8 +31,9 @@ use function Async\delay;
 
 require __DIR__ . '/_h2_client.inc';
 
-$port = 19830 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(10)
diff --git a/tests/phpt/server/h2/008-h2c-peer-reset-await-body.phpt b/tests/phpt/server/h2/008-h2c-peer-reset-await-body.phpt
index f6b7ddd..5bbe3ff 100644
--- a/tests/phpt/server/h2/008-h2c-peer-reset-await-body.phpt
+++ b/tests/phpt/server/h2/008-h2c-peer-reset-await-body.phpt
@@ -29,8 +29,9 @@ use function Async\delay;
 
 require __DIR__ . '/_h2_client.inc';
 
-$port = 19831 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(10)
diff --git a/tests/phpt/server/h2/009-h2-h2spec-gate.phpt b/tests/phpt/server/h2/009-h2-h2spec-gate.phpt
index 00b4435..45575c6 100644
--- a/tests/phpt/server/h2/009-h2-h2spec-gate.phpt
+++ b/tests/phpt/server/h2/009-h2-h2spec-gate.phpt
@@ -41,9 +41,9 @@ if ($h2spec === '' && is_executable($home = (string)getenv('HOME') . '/.local/bi
     $h2spec = $home;
 }
 
-$port = 19500 + getmypid() % 200;
+require_once __DIR__ . '/../_free_port.inc';
 
-// PHP_BINARY would re-enter THIS test under the phpt runner; use its
+$port = tas_free_port();
 // caller chain via posix or fall back to reading /proc/self/exe.
 $php = PHP_BINARY;
 
diff --git a/tests/phpt/server/h2/010-drain-proactive-age-h2-goaway.phpt b/tests/phpt/server/h2/010-drain-proactive-age-h2-goaway.phpt
index e93afef..8ba43ee 100644
--- a/tests/phpt/server/h2/010-drain-proactive-age-h2-goaway.phpt
+++ b/tests/phpt/server/h2/010-drain-proactive-age-h2-goaway.phpt
@@ -22,8 +22,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19842 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(10)
diff --git a/tests/phpt/server/h2/011-drain-h2-multiplex-completes.phpt b/tests/phpt/server/h2/011-drain-h2-multiplex-completes.phpt
index a71e8ef..c8dc030 100644
--- a/tests/phpt/server/h2/011-drain-h2-multiplex-completes.phpt
+++ b/tests/phpt/server/h2/011-drain-h2-multiplex-completes.phpt
@@ -21,8 +21,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19843 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(10)
diff --git a/tests/phpt/server/h2/013-h2-streaming-basic.phpt b/tests/phpt/server/h2/013-h2-streaming-basic.phpt
index 609c145..b7fc636 100644
--- a/tests/phpt/server/h2/013-h2-streaming-basic.phpt
+++ b/tests/phpt/server/h2/013-h2-streaming-basic.phpt
@@ -23,8 +23,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19850 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(10)
diff --git a/tests/phpt/server/h2/014-h2-streaming-large.phpt b/tests/phpt/server/h2/014-h2-streaming-large.phpt
index b38229f..278c4af 100644
--- a/tests/phpt/server/h2/014-h2-streaming-large.phpt
+++ b/tests/phpt/server/h2/014-h2-streaming-large.phpt
@@ -21,8 +21,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19851 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(10)
diff --git a/tests/phpt/server/h2/015-h2-streaming-backpressure.phpt b/tests/phpt/server/h2/015-h2-streaming-backpressure.phpt
index 0343b2a..7bbaf60 100644
--- a/tests/phpt/server/h2/015-h2-streaming-backpressure.phpt
+++ b/tests/phpt/server/h2/015-h2-streaming-backpressure.phpt
@@ -25,8 +25,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19870 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(15)
diff --git a/tests/phpt/server/h2/016-h2-streaming-telemetry.phpt b/tests/phpt/server/h2/016-h2-streaming-telemetry.phpt
index 15b453c..17f763a 100644
--- a/tests/phpt/server/h2/016-h2-streaming-telemetry.phpt
+++ b/tests/phpt/server/h2/016-h2-streaming-telemetry.phpt
@@ -20,8 +20,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19910 + getmypid() % 80;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $server = new HttpServer(
     (new HttpServerConfig())
         ->addListener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h2/017-h2-streaming-cancel.phpt b/tests/phpt/server/h2/017-h2-streaming-cancel.phpt
index f45d890..46a413a 100644
--- a/tests/phpt/server/h2/017-h2-streaming-cancel.phpt
+++ b/tests/phpt/server/h2/017-h2-streaming-cancel.phpt
@@ -32,8 +32,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19860 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $server = new HttpServer(
     (new HttpServerConfig())
         ->addListener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h2/018-h2-only-listener.phpt b/tests/phpt/server/h2/018-h2-only-listener.phpt
index ae79752..0118a1c 100644
--- a/tests/phpt/server/h2/018-h2-only-listener.phpt
+++ b/tests/phpt/server/h2/018-h2-only-listener.phpt
@@ -26,8 +26,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19880 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $server = new HttpServer(
     (new HttpServerConfig())
         ->addListener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h2/019-h2-stream-telemetry.phpt b/tests/phpt/server/h2/019-h2-stream-telemetry.phpt
index 2f3ecff..d514743 100644
--- a/tests/phpt/server/h2/019-h2-stream-telemetry.phpt
+++ b/tests/phpt/server/h2/019-h2-stream-telemetry.phpt
@@ -16,8 +16,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19900 + getmypid() % 80;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $server = new HttpServer(
     (new HttpServerConfig())
         ->addListener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h2/020-admission-reject-h2.phpt b/tests/phpt/server/h2/020-admission-reject-h2.phpt
index 924167e..9e35172 100644
--- a/tests/phpt/server/h2/020-admission-reject-h2.phpt
+++ b/tests/phpt/server/h2/020-admission-reject-h2.phpt
@@ -33,8 +33,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19980 + getmypid() % 10;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setMaxConnections(32)
diff --git a/tests/phpt/server/h2/021-h2-tls-multiplex.phpt b/tests/phpt/server/h2/021-h2-tls-multiplex.phpt
index 85d0250..4bfc4bf 100644
--- a/tests/phpt/server/h2/021-h2-tls-multiplex.phpt
+++ b/tests/phpt/server/h2/021-h2-tls-multiplex.phpt
@@ -46,7 +46,9 @@ if (!tls_gen_cert($key, $cert)) {
     exit(1);
 }
 
-$port = 19800 + getmypid() % 200;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $body_bytes = 256 * 1024;
 
 $config = (new HttpServerConfig())
diff --git a/tests/phpt/server/h2/022-h2-streaming-ring-full.phpt b/tests/phpt/server/h2/022-h2-streaming-ring-full.phpt
index f350982..6646960 100644
--- a/tests/phpt/server/h2/022-h2-streaming-ring-full.phpt
+++ b/tests/phpt/server/h2/022-h2-streaming-ring-full.phpt
@@ -30,8 +30,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19890 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $CHUNK_SZ = 8192;
 $N_CHUNKS = 64;
 
diff --git a/tests/phpt/server/h2/023-h2-streaming-sendable.phpt b/tests/phpt/server/h2/023-h2-streaming-sendable.phpt
index b1bb8db..d7f7478 100644
--- a/tests/phpt/server/h2/023-h2-streaming-sendable.phpt
+++ b/tests/phpt/server/h2/023-h2-streaming-sendable.phpt
@@ -25,8 +25,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19920 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $CHUNK_SZ = 8192;
 $N_CHUNKS = 48;
 
diff --git a/tests/phpt/server/h2/024-h2-tls-large-body.phpt b/tests/phpt/server/h2/024-h2-tls-large-body.phpt
index ea4d9a8..bb5720b 100644
--- a/tests/phpt/server/h2/024-h2-tls-large-body.phpt
+++ b/tests/phpt/server/h2/024-h2-tls-large-body.phpt
@@ -28,7 +28,9 @@ $cert = $tmp_dir . '/cert.pem';
 $key  = $tmp_dir . '/key.pem';
 if (!h2_gen_cert($key, $cert)) { echo "cert gen failed\n"; exit(1); }
 
-$port = 19890 + getmypid() % 20;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $size = 256 * 1024;
 $body = str_repeat('A', $size);
 
diff --git a/tests/phpt/server/h2/025-h2-sse-api.phpt b/tests/phpt/server/h2/025-h2-sse-api.phpt
index e26d196..0dc450c 100644
--- a/tests/phpt/server/h2/025-h2-sse-api.phpt
+++ b/tests/phpt/server/h2/025-h2-sse-api.phpt
@@ -20,8 +20,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19890 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(10)
diff --git a/tests/phpt/server/h2/026-h2-sse-empty-start.phpt b/tests/phpt/server/h2/026-h2-sse-empty-start.phpt
index cc405c2..9e78d84 100644
--- a/tests/phpt/server/h2/026-h2-sse-empty-start.phpt
+++ b/tests/phpt/server/h2/026-h2-sse-empty-start.phpt
@@ -23,8 +23,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19910 + getmypid() % 80;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(10)
diff --git a/tests/phpt/server/h2/050-stream-request-body.phpt b/tests/phpt/server/h2/050-stream-request-body.phpt
index a0783fe..d682e7f 100644
--- a/tests/phpt/server/h2/050-stream-request-body.phpt
+++ b/tests/phpt/server/h2/050-stream-request-body.phpt
@@ -15,8 +15,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19950 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $server = new HttpServer(
     (new HttpServerConfig())
         ->addListener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/001-h3-udp-recv.phpt b/tests/phpt/server/h3/001-h3-udp-recv.phpt
index d6a69f5..5aa936e 100644
--- a/tests/phpt/server/h3/001-h3-udp-recv.phpt
+++ b/tests/phpt/server/h3/001-h3-udp-recv.phpt
@@ -30,8 +30,9 @@ $cert_path = $tmp_dir . '/cert.pem';
 $key_path  = $tmp_dir . '/key.pem';
 if (!h3_gen_cert($key_path, $cert_path)) { echo "cert gen failed\n"; exit(1); }
 
-$port = 19900 + getmypid() % 100;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)  /* dummy TCP so start() has >=1 listener pre-H3 */
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/002-h3-packet-parse.phpt b/tests/phpt/server/h3/002-h3-packet-parse.phpt
index 2a703e8..9f0c960 100644
--- a/tests/phpt/server/h3/002-h3-packet-parse.phpt
+++ b/tests/phpt/server/h3/002-h3-packet-parse.phpt
@@ -39,8 +39,9 @@ $cert_path = $tmp_dir . '/cert.pem';
 $key_path  = $tmp_dir . '/key.pem';
 if (!h3_gen_cert($key_path, $cert_path)) { echo "cert gen failed\n"; exit(1); }
 
-$port = 19950 + getmypid() % 30;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/004-h3-start-without-cert.phpt b/tests/phpt/server/h3/004-h3-start-without-cert.phpt
index 9917b67..4244c9f 100644
--- a/tests/phpt/server/h3/004-h3-start-without-cert.phpt
+++ b/tests/phpt/server/h3/004-h3-start-without-cert.phpt
@@ -18,8 +18,9 @@ if (!class_exists('TrueAsync\HttpServer')) die('skip http_server not loaded');
 use TrueAsync\HttpServer;
 use TrueAsync\HttpServerConfig;
 
-$port = 20100 + getmypid() % 50;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addHttp3Listener('127.0.0.1', $port)
     ->setReadTimeout(2);
diff --git a/tests/phpt/server/h3/005-h3-repeat-initial-same-dcid.phpt b/tests/phpt/server/h3/005-h3-repeat-initial-same-dcid.phpt
index 58b2c74..10ea722 100644
--- a/tests/phpt/server/h3/005-h3-repeat-initial-same-dcid.phpt
+++ b/tests/phpt/server/h3/005-h3-repeat-initial-same-dcid.phpt
@@ -32,8 +32,9 @@ $cert_path = $tmp_dir . '/cert.pem';
 $key_path  = $tmp_dir . '/key.pem';
 if (!h3_gen_cert($key_path, $cert_path)) { echo "cert gen failed\n"; exit(1); }
 
-$port = 20150 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/008-h3-stats-handshake-keys.phpt b/tests/phpt/server/h3/008-h3-stats-handshake-keys.phpt
index f36d1da..e606a7d 100644
--- a/tests/phpt/server/h3/008-h3-stats-handshake-keys.phpt
+++ b/tests/phpt/server/h3/008-h3-stats-handshake-keys.phpt
@@ -33,8 +33,9 @@ $cert_path = $tmp_dir . '/cert.pem';
 $key_path  = $tmp_dir . '/key.pem';
 if (!h3_gen_cert($key_path, $cert_path)) { echo "cert gen failed\n"; exit(1); }
 
-$port = 20250 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/009-h3-e2e-get.phpt b/tests/phpt/server/h3/009-h3-e2e-get.phpt
index 1d4ccbf..0dd444e 100644
--- a/tests/phpt/server/h3/009-h3-e2e-get.phpt
+++ b/tests/phpt/server/h3/009-h3-e2e-get.phpt
@@ -40,8 +40,9 @@ exec(sprintf('openssl req -x509 -newkey rsa:2048 -sha256 -days 1 -nodes '
     escapeshellarg($key), escapeshellarg($cert)), $_, $rc);
 if ($rc !== 0) { echo "cert gen failed\n"; exit(1); }
 
-$port = 20300 + getmypid() % 50;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)   /* TCP listener required by start() */
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/010-h3-e2e-post-await-body.phpt b/tests/phpt/server/h3/010-h3-e2e-post-await-body.phpt
index 25c3ecf..c046b19 100644
--- a/tests/phpt/server/h3/010-h3-e2e-post-await-body.phpt
+++ b/tests/phpt/server/h3/010-h3-e2e-post-await-body.phpt
@@ -38,8 +38,9 @@ file_put_contents($body_path, $body);
 $expected = sprintf("len=%d sha1=%s method=POST",
     strlen($body), sha1($body));
 
-$port = 20400 + getmypid() % 50;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/011-h3-e2e-streaming-send.phpt b/tests/phpt/server/h3/011-h3-e2e-streaming-send.phpt
index 2a10613..1beecd1 100644
--- a/tests/phpt/server/h3/011-h3-e2e-streaming-send.phpt
+++ b/tests/phpt/server/h3/011-h3-e2e-streaming-send.phpt
@@ -47,8 +47,9 @@ $expected_body = implode('', $chunks);
 $expected_sha1 = sha1($expected_body);
 $expected_len  = strlen($expected_body);
 
-$port = 20500 + getmypid() % 50;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/012-h3-graceful-close.phpt b/tests/phpt/server/h3/012-h3-graceful-close.phpt
index 31b5bc0..0c59db0 100644
--- a/tests/phpt/server/h3/012-h3-graceful-close.phpt
+++ b/tests/phpt/server/h3/012-h3-graceful-close.phpt
@@ -33,8 +33,9 @@ exec(sprintf('openssl req -x509 -newkey rsa:2048 -sha256 -days 1 -nodes '
     escapeshellarg($key), escapeshellarg($cert)), $_, $rc);
 if ($rc !== 0) { echo "cert gen failed\n"; exit(1); }
 
-$port = 20400 + getmypid() % 50;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/013-h3-stateless-reset.phpt b/tests/phpt/server/h3/013-h3-stateless-reset.phpt
index d3b8500..47e8a8c 100644
--- a/tests/phpt/server/h3/013-h3-stateless-reset.phpt
+++ b/tests/phpt/server/h3/013-h3-stateless-reset.phpt
@@ -33,8 +33,9 @@ $cert = $tmp . '/cert.pem';
 $key  = $tmp . '/key.pem';
 if (!h3_gen_cert($key, $cert)) { echo "cert gen failed\n"; exit(1); }
 
-$port = 20500 + getmypid() % 50;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/014-h3-drain-max-conn-age.phpt b/tests/phpt/server/h3/014-h3-drain-max-conn-age.phpt
index 46261b9..1322fa9 100644
--- a/tests/phpt/server/h3/014-h3-drain-max-conn-age.phpt
+++ b/tests/phpt/server/h3/014-h3-drain-max-conn-age.phpt
@@ -33,8 +33,9 @@ exec(sprintf('openssl req -x509 -newkey rsa:2048 -sha256 -days 1 -nodes '
     escapeshellarg($key), escapeshellarg($cert)), $_, $rc);
 if ($rc !== 0) { echo "cert gen failed\n"; exit(1); }
 
-$port = 20600 + getmypid() % 50;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/015-h3-idle-timeout.phpt b/tests/phpt/server/h3/015-h3-idle-timeout.phpt
index 1608023..4e318db 100644
--- a/tests/phpt/server/h3/015-h3-idle-timeout.phpt
+++ b/tests/phpt/server/h3/015-h3-idle-timeout.phpt
@@ -37,8 +37,9 @@ if ($rc !== 0) { echo "cert gen failed\n"; exit(1); }
 
 putenv('PHP_HTTP3_IDLE_TIMEOUT_MS=500');
 
-$port = 20700 + getmypid() % 50;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/016-h3-per-peer-budget.phpt b/tests/phpt/server/h3/016-h3-per-peer-budget.phpt
index bdc8696..efc05a5 100644
--- a/tests/phpt/server/h3/016-h3-per-peer-budget.phpt
+++ b/tests/phpt/server/h3/016-h3-per-peer-budget.phpt
@@ -38,8 +38,9 @@ if ($rc !== 0) { echo "cert gen failed\n"; exit(1); }
 
 putenv('PHP_HTTP3_PEER_BUDGET=1');
 
-$port = 20800 + getmypid() % 50;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/017-h3-alt-svc-header.phpt b/tests/phpt/server/h3/017-h3-alt-svc-header.phpt
index 67ddf04..3525c76 100644
--- a/tests/phpt/server/h3/017-h3-alt-svc-header.phpt
+++ b/tests/phpt/server/h3/017-h3-alt-svc-header.phpt
@@ -63,7 +63,9 @@ function run_server(int $tcp_port, int $udp_port, string $cert, string $key, boo
     return $captured;
 }
 
-$port_tcp = 20900 + getmypid() % 50;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port_tcp = tas_free_port_span(11);
 $port_udp = $port_tcp + 1;
 
 $out = run_server($port_tcp, $port_udp, $cert, $key, /* disable */ false);
diff --git a/tests/phpt/server/h3/018-h3-version-negotiation.phpt b/tests/phpt/server/h3/018-h3-version-negotiation.phpt
index 6d3cdc0..10457b6 100644
--- a/tests/phpt/server/h3/018-h3-version-negotiation.phpt
+++ b/tests/phpt/server/h3/018-h3-version-negotiation.phpt
@@ -31,8 +31,9 @@ $cert = $tmp . '/cert.pem';
 $key  = $tmp . '/key.pem';
 if (!h3_gen_cert($key, $cert)) { echo "cert gen failed\n"; exit(1); }
 
-$port = 21000 + getmypid() % 50;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1, true)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/022-h3-stats-error-counters.phpt b/tests/phpt/server/h3/022-h3-stats-error-counters.phpt
index 5975c3d..b749955 100644
--- a/tests/phpt/server/h3/022-h3-stats-error-counters.phpt
+++ b/tests/phpt/server/h3/022-h3-stats-error-counters.phpt
@@ -29,8 +29,9 @@ $cert_path = $tmp_dir . '/cert.pem';
 $key_path  = $tmp_dir . '/key.pem';
 if (!h3_gen_cert($key_path, $cert_path)) { echo "cert gen failed\n"; exit(1); }
 
-$port = 20300 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/024-h3-config-setters-e2e.phpt b/tests/phpt/server/h3/024-h3-config-setters-e2e.phpt
index 8bec6ec..9977c0d 100644
--- a/tests/phpt/server/h3/024-h3-config-setters-e2e.phpt
+++ b/tests/phpt/server/h3/024-h3-config-setters-e2e.phpt
@@ -38,8 +38,9 @@ exec(sprintf('openssl req -x509 -newkey rsa:2048 -sha256 -days 1 -nodes '
     escapeshellarg($key), escapeshellarg($cert)), $_, $rc);
 if ($rc !== 0) { echo "cert gen failed\n"; exit(1); }
 
-$port = 20920 + getmypid() % 50;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/025-h3-retry-token.phpt b/tests/phpt/server/h3/025-h3-retry-token.phpt
index 9415c7a..3467f16 100644
--- a/tests/phpt/server/h3/025-h3-retry-token.phpt
+++ b/tests/phpt/server/h3/025-h3-retry-token.phpt
@@ -25,8 +25,9 @@ exec(sprintf('openssl req -x509 -newkey rsa:2048 -sha256 -days 1 -nodes '
     escapeshellarg($key), escapeshellarg($cert)), $_, $rc);
 if ($rc !== 0) { echo "cert gen failed\n"; exit(1); }
 
-$port = 20420 + getmypid() % 30;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/026-h3-static-file.phpt b/tests/phpt/server/h3/026-h3-static-file.phpt
index e392e60..f5852f1 100644
--- a/tests/phpt/server/h3/026-h3-static-file.phpt
+++ b/tests/phpt/server/h3/026-h3-static-file.phpt
@@ -55,8 +55,9 @@ register_shutdown_function(function () use ($tmp, $root, $sizes) {
     @rmdir($root); @rmdir($tmp);
 });
 
-$port = 20360 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/027-h3-static-mount.phpt b/tests/phpt/server/h3/027-h3-static-mount.phpt
index 10c1d6c..162ac93 100644
--- a/tests/phpt/server/h3/027-h3-static-mount.phpt
+++ b/tests/phpt/server/h3/027-h3-static-mount.phpt
@@ -58,8 +58,9 @@ register_shutdown_function(function () use ($tmp, $root, $sizes) {
     @rmdir($root); @rmdir($tmp);
 });
 
-$port = 20400 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/028-h3-large-body.phpt b/tests/phpt/server/h3/028-h3-large-body.phpt
index 9a5b6cf..f680b7c 100644
--- a/tests/phpt/server/h3/028-h3-large-body.phpt
+++ b/tests/phpt/server/h3/028-h3-large-body.phpt
@@ -38,9 +38,9 @@ register_shutdown_function(function () use ($tmp, $cert, $key) {
     @unlink($cert); @unlink($key); @rmdir($tmp);
 });
 
-$port = 20440 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
-/* Position-varying content so a reorder/truncation shows as a sha1 miss. */
+$port = tas_free_port_span(2);
 $size = 2 * 1024 * 1024;
 $body = str_repeat("\0", $size);
 for ($i = 0; $i < $size; $i++) { $body[$i] = chr(($i * 31 + 7) & 0xff); }
diff --git a/tests/phpt/server/h3/029-h3-pacing-setter.phpt b/tests/phpt/server/h3/029-h3-pacing-setter.phpt
index 93e6fb1..424e67a 100644
--- a/tests/phpt/server/h3/029-h3-pacing-setter.phpt
+++ b/tests/phpt/server/h3/029-h3-pacing-setter.phpt
@@ -42,7 +42,9 @@ register_shutdown_function(function () use ($tmp, $cert, $key) {
     @unlink($cert); @unlink($key); @rmdir($tmp);
 });
 
-$port = 20460 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port_span(2);
 $size = 256 * 1024;
 $body = str_repeat("\0", $size);
 for ($i = 0; $i < $size; $i++) { $body[$i] = chr(($i * 31 + 7) & 0xff); }
diff --git a/tests/phpt/server/h3/031-h3-stats-nonzero-after-traffic.phpt b/tests/phpt/server/h3/031-h3-stats-nonzero-after-traffic.phpt
index f854ab7..d601178 100644
--- a/tests/phpt/server/h3/031-h3-stats-nonzero-after-traffic.phpt
+++ b/tests/phpt/server/h3/031-h3-stats-nonzero-after-traffic.phpt
@@ -33,8 +33,9 @@ register_shutdown_function(function () use ($tmp, $cert, $key) {
     @unlink($cert); @unlink($key); @rmdir($tmp);
 });
 
-$port = 20560 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/032-h3-connection-migration.phpt b/tests/phpt/server/h3/032-h3-connection-migration.phpt
index bce1a11..6ee050d 100644
--- a/tests/phpt/server/h3/032-h3-connection-migration.phpt
+++ b/tests/phpt/server/h3/032-h3-connection-migration.phpt
@@ -39,8 +39,9 @@ register_shutdown_function(function () use ($tmp, $cert, $key) {
     @unlink($cert); @unlink($key); @rmdir($tmp);
 });
 
-$port = 21100 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/033-h3-head-request.phpt b/tests/phpt/server/h3/033-h3-head-request.phpt
index 2348421..0e77191 100644
--- a/tests/phpt/server/h3/033-h3-head-request.phpt
+++ b/tests/phpt/server/h3/033-h3-head-request.phpt
@@ -31,8 +31,9 @@ register_shutdown_function(function () use ($tmp, $cert, $key) {
     @unlink($cert); @unlink($key); @rmdir($tmp);
 });
 
-$port = 20760 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/034-h3-stateless-reset-clamps.phpt b/tests/phpt/server/h3/034-h3-stateless-reset-clamps.phpt
index 3d3ddd0..b6ab2b6 100644
--- a/tests/phpt/server/h3/034-h3-stateless-reset-clamps.phpt
+++ b/tests/phpt/server/h3/034-h3-stateless-reset-clamps.phpt
@@ -35,8 +35,9 @@ register_shutdown_function(function () use ($tmp, $cert, $key) {
     @unlink($cert); @unlink($key); @rmdir($tmp);
 });
 
-$port = 20680 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/035-h3-request-body-overflow.phpt b/tests/phpt/server/h3/035-h3-request-body-overflow.phpt
index e7aee21..5e4e76a 100644
--- a/tests/phpt/server/h3/035-h3-request-body-overflow.phpt
+++ b/tests/phpt/server/h3/035-h3-request-body-overflow.phpt
@@ -39,8 +39,9 @@ register_shutdown_function(function () use ($tmp, $cert, $key, $big) {
     @unlink($cert); @unlink($key); @unlink($big); @rmdir($tmp);
 });
 
-$port = 20720 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/037-h3-reactor-pool-e2e.phpt b/tests/phpt/server/h3/037-h3-reactor-pool-e2e.phpt
index 7e5fa64..e96be10 100644
--- a/tests/phpt/server/h3/037-h3-reactor-pool-e2e.phpt
+++ b/tests/phpt/server/h3/037-h3-reactor-pool-e2e.phpt
@@ -45,8 +45,9 @@ register_shutdown_function(function () use ($tmp, $cert, $key) {
     @unlink($cert); @unlink($key); @rmdir($tmp);
 });
 
-$port = 21300 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)   /* TCP listener required by start() */
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/038-h3-reactor-pool-post.phpt b/tests/phpt/server/h3/038-h3-reactor-pool-post.phpt
index e83133f..2a3bba9 100644
--- a/tests/phpt/server/h3/038-h3-reactor-pool-post.phpt
+++ b/tests/phpt/server/h3/038-h3-reactor-pool-post.phpt
@@ -49,8 +49,9 @@ register_shutdown_function(function () use ($tmp, $cert, $key, $body_path) {
     @unlink($cert); @unlink($key); @unlink($body_path); @rmdir($tmp);
 });
 
-$port = 21380 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/039-h3-reactor-pool-static.phpt b/tests/phpt/server/h3/039-h3-reactor-pool-static.phpt
index 90c7392..d2e55de 100644
--- a/tests/phpt/server/h3/039-h3-reactor-pool-static.phpt
+++ b/tests/phpt/server/h3/039-h3-reactor-pool-static.phpt
@@ -52,8 +52,9 @@ register_shutdown_function(function () use ($tmp, $cert, $key, $root) {
     @rmdir($root); @rmdir($tmp);
 });
 
-$port = 21420 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/040-h3-reactor-pool-steering.phpt b/tests/phpt/server/h3/040-h3-reactor-pool-steering.phpt
index 94876ae..0f25e29 100644
--- a/tests/phpt/server/h3/040-h3-reactor-pool-steering.phpt
+++ b/tests/phpt/server/h3/040-h3-reactor-pool-steering.phpt
@@ -55,8 +55,9 @@ register_shutdown_function(function () use ($tmp, $cert, $key) {
     @unlink($cert); @unlink($key); @rmdir($tmp);
 });
 
-$port = 21340 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)   /* TCP listener required by start() */
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/041-h3-migration-storm-guard.phpt b/tests/phpt/server/h3/041-h3-migration-storm-guard.phpt
index 15c0ea3..5917d21 100644
--- a/tests/phpt/server/h3/041-h3-migration-storm-guard.phpt
+++ b/tests/phpt/server/h3/041-h3-migration-storm-guard.phpt
@@ -55,8 +55,9 @@ register_shutdown_function(function () use ($tmp, $cert, $key) {
     @unlink($cert); @unlink($key); @rmdir($tmp);
 });
 
-$port = 21380 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)   /* TCP listener required by start() */
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/041-h3-sse-api.phpt b/tests/phpt/server/h3/041-h3-sse-api.phpt
index e240d9d..5a52ae2 100644
--- a/tests/phpt/server/h3/041-h3-sse-api.phpt
+++ b/tests/phpt/server/h3/041-h3-sse-api.phpt
@@ -36,8 +36,9 @@ $expected_body =
     "data: multi\ndata: line\n\n" .
     "id: 7\nevent: ping\ndata: named\n\n";
 
-$port = 20560 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/042-h3-newcid-dcid-rotation.phpt b/tests/phpt/server/h3/042-h3-newcid-dcid-rotation.phpt
index 3fc45c6..f923b66 100644
--- a/tests/phpt/server/h3/042-h3-newcid-dcid-rotation.phpt
+++ b/tests/phpt/server/h3/042-h3-newcid-dcid-rotation.phpt
@@ -41,8 +41,9 @@ register_shutdown_function(function () use ($tmp, $cert, $key) {
     @unlink($cert); @unlink($key); @rmdir($tmp);
 });
 
-$port = 21420 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/042-h3-sse-empty-start.phpt b/tests/phpt/server/h3/042-h3-sse-empty-start.phpt
index 046e8b7..8902df1 100644
--- a/tests/phpt/server/h3/042-h3-sse-empty-start.phpt
+++ b/tests/phpt/server/h3/042-h3-sse-empty-start.phpt
@@ -32,8 +32,9 @@ exec(sprintf('openssl req -x509 -newkey rsa:2048 -sha256 -days 1 -nodes '
     escapeshellarg($key), escapeshellarg($cert)), $_, $rc);
 if ($rc !== 0) { echo "cert gen failed\n"; exit(1); }
 
-$port = 20600 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/043-h3-newcid-multi-rotation.phpt b/tests/phpt/server/h3/043-h3-newcid-multi-rotation.phpt
index c24417e..2b5e28b 100644
--- a/tests/phpt/server/h3/043-h3-newcid-multi-rotation.phpt
+++ b/tests/phpt/server/h3/043-h3-newcid-multi-rotation.phpt
@@ -36,8 +36,9 @@ register_shutdown_function(function () use ($tmp, $cert, $key) {
     @unlink($cert); @unlink($key); @rmdir($tmp);
 });
 
-$port = 21460 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/h3/044-hq-interop-file.phpt b/tests/phpt/server/h3/044-hq-interop-file.phpt
index ca36d2f..d35790c 100644
--- a/tests/phpt/server/h3/044-hq-interop-file.phpt
+++ b/tests/phpt/server/h3/044-hq-interop-file.phpt
@@ -55,8 +55,9 @@ register_shutdown_function(function () use ($tmp, $root, $sizes) {
     @rmdir($root); @rmdir($tmp);
 });
 
-$port = 20460 + getmypid() % 40;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port + 1)
     ->addHttp3Listener('127.0.0.1', $port)
diff --git a/tests/phpt/server/sendfile/001-sendfile-basic.phpt b/tests/phpt/server/sendfile/001-sendfile-basic.phpt
index 3f8f02d..c21626a 100644
--- a/tests/phpt/server/sendfile/001-sendfile-basic.phpt
+++ b/tests/phpt/server/sendfile/001-sendfile-basic.phpt
@@ -17,7 +17,9 @@ file_put_contents($tmp, "body{margin:0}");
 
 register_shutdown_function(function() use ($tmp) { @unlink($tmp); });
 
-$port = 28310 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 $server->addHttpHandler(function ($req, $res) use ($tmp) {
diff --git a/tests/phpt/server/sendfile/002-sendfile-options.phpt b/tests/phpt/server/sendfile/002-sendfile-options.phpt
index 855195b..299e5d3 100644
--- a/tests/phpt/server/sendfile/002-sendfile-options.phpt
+++ b/tests/phpt/server/sendfile/002-sendfile-options.phpt
@@ -17,7 +17,9 @@ file_put_contents($tmp, "abcdef");
 
 register_shutdown_function(function() use ($tmp) { @unlink($tmp); });
 
-$port = 28320 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 $server->addHttpHandler(function ($req, $res) use ($tmp) {
diff --git a/tests/phpt/server/sendfile/003-sendfile-sealed.phpt b/tests/phpt/server/sendfile/003-sendfile-sealed.phpt
index 373fee7..d580d5f 100644
--- a/tests/phpt/server/sendfile/003-sendfile-sealed.phpt
+++ b/tests/phpt/server/sendfile/003-sendfile-sealed.phpt
@@ -16,7 +16,9 @@ file_put_contents($tmp, "ZZZZZ");
 
 register_shutdown_function(function() use ($tmp) { @unlink($tmp); });
 
-$port = 28330 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 $server->addHttpHandler(function ($req, $res) use ($tmp) {
diff --git a/tests/phpt/server/sendfile/004-sendfile-errors.phpt b/tests/phpt/server/sendfile/004-sendfile-errors.phpt
index b3f6781..7c1b036 100644
--- a/tests/phpt/server/sendfile/004-sendfile-errors.phpt
+++ b/tests/phpt/server/sendfile/004-sendfile-errors.phpt
@@ -10,7 +10,9 @@ use TrueAsync\HttpServerConfig;
 use function Async\spawn;
 use function Async\await;
 
-$port = 28340 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 $server->addHttpHandler(function ($req, $res) {
diff --git a/tests/phpt/server/sendfile/005-sendfile-rfc5987.phpt b/tests/phpt/server/sendfile/005-sendfile-rfc5987.phpt
index c13f9d2..0b8c4eb 100644
--- a/tests/phpt/server/sendfile/005-sendfile-rfc5987.phpt
+++ b/tests/phpt/server/sendfile/005-sendfile-rfc5987.phpt
@@ -31,7 +31,9 @@ $cases = [
             "attachment; filename*=UTF-8''a%22b.txt"],
 ];
 
-$port   = 28430 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 $server->addHttpHandler(function ($req, $res) use ($tmp, $cases) {
diff --git a/tests/phpt/server/static/001-static-basic.phpt b/tests/phpt/server/static/001-static-basic.phpt
index 9606e1c..0cb1499 100644
--- a/tests/phpt/server/static/001-static-basic.phpt
+++ b/tests/phpt/server/static/001-static-basic.phpt
@@ -27,7 +27,9 @@ register_shutdown_function(function() use ($root) {
     @rmdir($root);
 });
 
-$port = 19817 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 $h = (new StaticHandler('/static/', $root))->setIndexFiles('index.html');
diff --git a/tests/phpt/server/static/002-static-dotfile-and-onmissing.phpt b/tests/phpt/server/static/002-static-dotfile-and-onmissing.phpt
index 8ff376b..f1ffc1f 100644
--- a/tests/phpt/server/static/002-static-dotfile-and-onmissing.phpt
+++ b/tests/phpt/server/static/002-static-dotfile-and-onmissing.phpt
@@ -25,7 +25,9 @@ register_shutdown_function(function() use ($root) {
     @rmdir($root);
 });
 
-$port = 19817 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 
diff --git a/tests/phpt/server/static/003-static-security.phpt b/tests/phpt/server/static/003-static-security.phpt
index 4b86e44..3bf2310 100644
--- a/tests/phpt/server/static/003-static-security.phpt
+++ b/tests/phpt/server/static/003-static-security.phpt
@@ -49,7 +49,9 @@ register_shutdown_function(function() use ($base, $forbidden) {
     $rm($base);
 });
 
-$port = 19817 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 $h = new StaticHandler('/static/', $root);
diff --git a/tests/phpt/server/static/004-static-workers.phpt b/tests/phpt/server/static/004-static-workers.phpt
index c70ed1d..27ba548 100644
--- a/tests/phpt/server/static/004-static-workers.phpt
+++ b/tests/phpt/server/static/004-static-workers.phpt
@@ -30,7 +30,9 @@ register_shutdown_function(function() use ($root) {
     @rmdir($root);
 });
 
-$port = 19940 + getmypid() % 50;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $workers = 2;
 
 $config = (new HttpServerConfig())
diff --git a/tests/phpt/server/static/005-static-if-modified-since.phpt b/tests/phpt/server/static/005-static-if-modified-since.phpt
index 7dfc88a..c4e858f 100644
--- a/tests/phpt/server/static/005-static-if-modified-since.phpt
+++ b/tests/phpt/server/static/005-static-if-modified-since.phpt
@@ -30,7 +30,9 @@ register_shutdown_function(function() use ($root) {
     @rmdir($root);
 });
 
-$port = 19960 + getmypid() % 30;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 $server->addStaticHandler(new StaticHandler('/static/', $root));
diff --git a/tests/phpt/server/static/006-static-zero-coroutine-counter.phpt b/tests/phpt/server/static/006-static-zero-coroutine-counter.phpt
index c87666e..b7cc35b 100644
--- a/tests/phpt/server/static/006-static-zero-coroutine-counter.phpt
+++ b/tests/phpt/server/static/006-static-zero-coroutine-counter.phpt
@@ -27,7 +27,9 @@ register_shutdown_function(function() use ($root) {
     @rmdir($root);
 });
 
-$port = 19990 + getmypid() % 9;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 $server->addStaticHandler((new StaticHandler('/static/', $root))->disableIndex());
diff --git a/tests/phpt/server/static/007-static-tls-streaming.phpt b/tests/phpt/server/static/007-static-tls-streaming.phpt
index 7d72461..935526d 100644
--- a/tests/phpt/server/static/007-static-tls-streaming.phpt
+++ b/tests/phpt/server/static/007-static-tls-streaming.phpt
@@ -38,8 +38,9 @@ register_shutdown_function(function() use ($root, $tmp) {
     @rmdir($tmp);
 });
 
-$port = 19960 + getmypid() % 20;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port, true)
     ->enableTls(true)
diff --git a/tests/phpt/server/static/008-static-cache-counters.phpt b/tests/phpt/server/static/008-static-cache-counters.phpt
index bc60a3a..ad80673 100644
--- a/tests/phpt/server/static/008-static-cache-counters.phpt
+++ b/tests/phpt/server/static/008-static-cache-counters.phpt
@@ -28,7 +28,9 @@ register_shutdown_function(function() use ($root) {
     @rmdir($root);
 });
 
-$port = 19940 + getmypid() % 9;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 $server->addStaticHandler(
diff --git a/tests/phpt/server/static/009-static-symlink-owner.phpt b/tests/phpt/server/static/009-static-symlink-owner.phpt
index d27cbca..91189c9 100644
--- a/tests/phpt/server/static/009-static-symlink-owner.phpt
+++ b/tests/phpt/server/static/009-static-symlink-owner.phpt
@@ -45,7 +45,9 @@ register_shutdown_function(function() use ($root) {
     @rmdir($root);
 });
 
-$port = 19960 + getmypid() % 9;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 
diff --git a/tests/phpt/server/static/010-static-precompressed.phpt b/tests/phpt/server/static/010-static-precompressed.phpt
index bca15c0..d803be5 100644
--- a/tests/phpt/server/static/010-static-precompressed.phpt
+++ b/tests/phpt/server/static/010-static-precompressed.phpt
@@ -38,7 +38,9 @@ register_shutdown_function(function() use ($root) {
     @rmdir($root);
 });
 
-$port = 19930 + getmypid() % 9;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 $server->addStaticHandler(
diff --git a/tests/phpt/server/static/011-static-precompressed-cache-uaf.phpt b/tests/phpt/server/static/011-static-precompressed-cache-uaf.phpt
index 87aef55..71c6e1a 100644
--- a/tests/phpt/server/static/011-static-precompressed-cache-uaf.phpt
+++ b/tests/phpt/server/static/011-static-precompressed-cache-uaf.phpt
@@ -41,7 +41,9 @@ register_shutdown_function(function() use ($root) {
     @rmdir($root);
 });
 
-$port = 19460 + getmypid() % 9;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 $server->addStaticHandler(
diff --git a/tests/phpt/server/static/011-static-range.phpt b/tests/phpt/server/static/011-static-range.phpt
index ab13e1d..857c192 100644
--- a/tests/phpt/server/static/011-static-range.phpt
+++ b/tests/phpt/server/static/011-static-range.phpt
@@ -28,7 +28,9 @@ register_shutdown_function(function() use ($root) {
     @rmdir($root);
 });
 
-$port = 19920 + getmypid() % 9;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 $server->addStaticHandler((new StaticHandler('/r/', $root))->disableIndex());
diff --git a/tests/phpt/server/static/012-static-h2.phpt b/tests/phpt/server/static/012-static-h2.phpt
index 58927d7..d9e8196 100644
--- a/tests/phpt/server/static/012-static-h2.phpt
+++ b/tests/phpt/server/static/012-static-h2.phpt
@@ -38,7 +38,9 @@ register_shutdown_function(function() use ($root) {
     @rmdir($root);
 });
 
-$port = 19940 + getmypid() % 50;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 $server->addStaticHandler(
diff --git a/tests/phpt/server/static/012-static-precompressed-small-cache-headers.phpt b/tests/phpt/server/static/012-static-precompressed-small-cache-headers.phpt
index 318165a..9109dc4 100644
--- a/tests/phpt/server/static/012-static-precompressed-small-cache-headers.phpt
+++ b/tests/phpt/server/static/012-static-precompressed-small-cache-headers.phpt
@@ -43,7 +43,9 @@ register_shutdown_function(function() use ($root) {
     @rmdir($root);
 });
 
-$port = 19480 + getmypid() % 9;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 $server->addStaticHandler(
diff --git a/tests/phpt/server/static/013-static-h2-tls.phpt b/tests/phpt/server/static/013-static-h2-tls.phpt
index e4a0dd1..9e3e753 100644
--- a/tests/phpt/server/static/013-static-h2-tls.phpt
+++ b/tests/phpt/server/static/013-static-h2-tls.phpt
@@ -49,8 +49,9 @@ register_shutdown_function(function() use ($root, $tmp) {
     @rmdir($tmp);
 });
 
-$port = 19980 + getmypid() % 15;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port, true)
     ->enableTls(true)
diff --git a/tests/phpt/server/static/014-static-body-cache.phpt b/tests/phpt/server/static/014-static-body-cache.phpt
index 7cfd39a..5dfa33a 100644
--- a/tests/phpt/server/static/014-static-body-cache.phpt
+++ b/tests/phpt/server/static/014-static-body-cache.phpt
@@ -27,7 +27,9 @@ register_shutdown_function(function () use ($root) {
     @rmdir($root);
 });
 
-$port = 19960 + getmypid() % 9;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 $server->addStaticHandler(
diff --git a/tests/phpt/server/static/015-static-ims-date-formats.phpt b/tests/phpt/server/static/015-static-ims-date-formats.phpt
index c0fdb2f..cc1c891 100644
--- a/tests/phpt/server/static/015-static-ims-date-formats.phpt
+++ b/tests/phpt/server/static/015-static-ims-date-formats.phpt
@@ -27,7 +27,9 @@ register_shutdown_function(function() use ($root) {
     @rmdir($root);
 });
 
-$port = 20040 + getmypid() % 30;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 $server->addStaticHandler(new StaticHandler('/s/', $root));
diff --git a/tests/phpt/server/static/017-static-handler-locked.phpt b/tests/phpt/server/static/017-static-handler-locked.phpt
index 458344c..617b8af 100644
--- a/tests/phpt/server/static/017-static-handler-locked.phpt
+++ b/tests/phpt/server/static/017-static-handler-locked.phpt
@@ -21,7 +21,9 @@ $root = sys_get_temp_dir() . '/sh-lock-' . getmypid() . '-' . bin2hex(random_byt
 mkdir($root, 0700, true);
 register_shutdown_function(fn() => @rmdir($root));
 
-$port   = 28560 + getmypid() % 1000;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $sh     = new StaticHandler('/s/', $root);
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
diff --git a/tests/phpt/server/static/018-static-hide-index-mime.phpt b/tests/phpt/server/static/018-static-hide-index-mime.phpt
index bab913e..0784339 100644
--- a/tests/phpt/server/static/018-static-hide-index-mime.phpt
+++ b/tests/phpt/server/static/018-static-hide-index-mime.phpt
@@ -38,7 +38,9 @@ register_shutdown_function(function() use ($root1, $root2) {
     @rmdir("$root1/sub"); @rmdir($root1); @rmdir($root2);
 });
 
-$port   = 19880 + getmypid() % 30;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 
diff --git a/tests/phpt/server/static/019-static-dotfile-ignore-and-noindex.phpt b/tests/phpt/server/static/019-static-dotfile-ignore-and-noindex.phpt
index e07613d..932f70a 100644
--- a/tests/phpt/server/static/019-static-dotfile-ignore-and-noindex.phpt
+++ b/tests/phpt/server/static/019-static-dotfile-ignore-and-noindex.phpt
@@ -35,7 +35,9 @@ register_shutdown_function(function() use ($root) {
     @rmdir($root);
 });
 
-$port   = 19960 + getmypid() % 30;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 
diff --git a/tests/phpt/server/static/020-static-extra-headers-and-mime.phpt b/tests/phpt/server/static/020-static-extra-headers-and-mime.phpt
index 6fa3cbf..d0e0137 100644
--- a/tests/phpt/server/static/020-static-extra-headers-and-mime.phpt
+++ b/tests/phpt/server/static/020-static-extra-headers-and-mime.phpt
@@ -27,7 +27,9 @@ register_shutdown_function(function() use ($root) {
     @unlink("$root/page.mdx"); @rmdir($root);
 });
 
-$port   = 20040 + getmypid() % 30;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 $h = (new StaticHandler('/s/', $root))
diff --git a/tests/phpt/server/static/021-static-symlink-reject-nofollow.phpt b/tests/phpt/server/static/021-static-symlink-reject-nofollow.phpt
index b2569cc..d95174e 100644
--- a/tests/phpt/server/static/021-static-symlink-reject-nofollow.phpt
+++ b/tests/phpt/server/static/021-static-symlink-reject-nofollow.phpt
@@ -46,7 +46,9 @@ register_shutdown_function(function() use ($root, $secret) {
     @unlink($secret);
 });
 
-$port = 19970 + getmypid() % 9;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port);
 $server = new HttpServer($config);
 $server->addStaticHandler(
diff --git a/tests/phpt/server/tls/002-tls-config.phpt b/tests/phpt/server/tls/002-tls-config.phpt
index eef50d6..fe6dce8 100644
--- a/tests/phpt/server/tls/002-tls-config.phpt
+++ b/tests/phpt/server/tls/002-tls-config.phpt
@@ -29,9 +29,9 @@ if (!tls_gen_cert($key_path, $cert_path)) {
     exit(1);
 }
 
-$port = 19960 + getmypid() % 30;
+require_once __DIR__ . '/../_free_port.inc';
 
-// --- Case 1: TLS listener with valid cert/key starts and stops cleanly.
+$port = tas_free_port_span(2);
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port, true)   // tls=true
     ->enableTls(true)
diff --git a/tests/phpt/server/tls/003-tls-handshake.phpt b/tests/phpt/server/tls/003-tls-handshake.phpt
index 81b2979..cf169f2 100644
--- a/tests/phpt/server/tls/003-tls-handshake.phpt
+++ b/tests/phpt/server/tls/003-tls-handshake.phpt
@@ -29,8 +29,9 @@ if (!tls_gen_cert($key_path, $cert_path)) {
     exit(1);
 }
 
-$port = 19970 + getmypid() % 20;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port, true)   // tls=true
     ->enableTls(true)
diff --git a/tests/phpt/server/tls/004-tls-get.phpt b/tests/phpt/server/tls/004-tls-get.phpt
index 3e221db..5ddd7cc 100644
--- a/tests/phpt/server/tls/004-tls-get.phpt
+++ b/tests/phpt/server/tls/004-tls-get.phpt
@@ -26,8 +26,9 @@ if (!tls_gen_cert($key, $cert)) {
     exit(1);
 }
 
-$port = 19940 + getmypid() % 20;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port, true)
     ->enableTls(true)
diff --git a/tests/phpt/server/tls/005-tls-body.phpt b/tests/phpt/server/tls/005-tls-body.phpt
index 447fa3e..0e55d43 100644
--- a/tests/phpt/server/tls/005-tls-body.phpt
+++ b/tests/phpt/server/tls/005-tls-body.phpt
@@ -40,8 +40,9 @@ $buf = substr($buf, 0, $size);
 file_put_contents($payload, $buf);
 $expected_sha1 = sha1($buf);
 
-$port = 19920 + getmypid() % 20;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port, true)
     ->enableTls(true)
diff --git a/tests/phpt/server/tls/006-tls-keepalive.phpt b/tests/phpt/server/tls/006-tls-keepalive.phpt
index 21171ac..01bd5d4 100644
--- a/tests/phpt/server/tls/006-tls-keepalive.phpt
+++ b/tests/phpt/server/tls/006-tls-keepalive.phpt
@@ -25,8 +25,9 @@ if (!tls_gen_cert($key, $cert)) {
     exit(1);
 }
 
-$port = 19880 + getmypid() % 20;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port, true)
     ->enableTls(true)
diff --git a/tests/phpt/server/tls/007-tls-pipelining.phpt b/tests/phpt/server/tls/007-tls-pipelining.phpt
index 00ac443..eda0ef6 100644
--- a/tests/phpt/server/tls/007-tls-pipelining.phpt
+++ b/tests/phpt/server/tls/007-tls-pipelining.phpt
@@ -34,8 +34,9 @@ if (!tls_gen_cert($key, $cert)) {
     exit(1);
 }
 
-$port = 19860 + getmypid() % 20;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port, true)
     ->enableTls(true)
diff --git a/tests/phpt/server/tls/008-tls-telemetry.phpt b/tests/phpt/server/tls/008-tls-telemetry.phpt
index 5d5ac4a..156af92 100644
--- a/tests/phpt/server/tls/008-tls-telemetry.phpt
+++ b/tests/phpt/server/tls/008-tls-telemetry.phpt
@@ -25,8 +25,9 @@ if (!tls_gen_cert($key, $cert)) {
     exit(1);
 }
 
-$port = 19820 + getmypid() % 20;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port, true)
     ->enableTls(true)
diff --git a/tests/phpt/server/tls/009-tls-resumption.phpt b/tests/phpt/server/tls/009-tls-resumption.phpt
index acd90c4..c243d13 100644
--- a/tests/phpt/server/tls/009-tls-resumption.phpt
+++ b/tests/phpt/server/tls/009-tls-resumption.phpt
@@ -32,8 +32,9 @@ if (!tls_gen_cert($key, $cert)) {
     exit(1);
 }
 
-$port = 19800 + getmypid() % 20;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port, true)
     ->enableTls(true)
diff --git a/tests/phpt/server/tls/010-tls-ktls.phpt b/tests/phpt/server/tls/010-tls-ktls.phpt
index 2b42e35..ca911ed 100644
--- a/tests/phpt/server/tls/010-tls-ktls.phpt
+++ b/tests/phpt/server/tls/010-tls-ktls.phpt
@@ -25,8 +25,9 @@ if (!tls_gen_cert($key, $cert)) {
     exit(1);
 }
 
-$port = 19780 + getmypid() % 20;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port, true)
     ->enableTls(true)
diff --git a/tests/phpt/server/tls/011-tls-parse-error.phpt b/tests/phpt/server/tls/011-tls-parse-error.phpt
index 32b5aec..196e87f 100644
--- a/tests/phpt/server/tls/011-tls-parse-error.phpt
+++ b/tests/phpt/server/tls/011-tls-parse-error.phpt
@@ -26,8 +26,9 @@ if (!tls_gen_cert($key, $cert)) {
     exit(1);
 }
 
-$port = 19960 + getmypid() % 20;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port, true)
     ->enableTls(true)
diff --git a/tests/phpt/server/tls/012-tls-security-level.phpt b/tests/phpt/server/tls/012-tls-security-level.phpt
index 90b28ca..490fd72 100644
--- a/tests/phpt/server/tls/012-tls-security-level.phpt
+++ b/tests/phpt/server/tls/012-tls-security-level.phpt
@@ -27,7 +27,9 @@ if (!tls_gen_cert($key_path, $cert_path, 1024, 'sha1')) {
     exit(1);
 }
 
-$port = 19990 + getmypid() % 20;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port, true)
     ->enableTls(true)
diff --git a/tests/phpt/server/tls/013-tls-abrupt-and-plain-on-tls.phpt b/tests/phpt/server/tls/013-tls-abrupt-and-plain-on-tls.phpt
index d4b2b33..f0398f8 100644
--- a/tests/phpt/server/tls/013-tls-abrupt-and-plain-on-tls.phpt
+++ b/tests/phpt/server/tls/013-tls-abrupt-and-plain-on-tls.phpt
@@ -26,8 +26,9 @@ if (!tls_gen_cert($key, $cert)) {
     exit(1);
 }
 
-$port = 19990 + getmypid() % 9;
+require_once __DIR__ . '/../_free_port.inc';
 
+$port = tas_free_port();
 $server = new HttpServer((new HttpServerConfig())
     ->addListener('127.0.0.1', $port, true)
     ->enableTls(true)
diff --git a/tests/phpt/server/tls/014-tls-h2-large-body-bio-park.phpt b/tests/phpt/server/tls/014-tls-h2-large-body-bio-park.phpt
index 2f076c9..97ae49b 100644
--- a/tests/phpt/server/tls/014-tls-h2-large-body-bio-park.phpt
+++ b/tests/phpt/server/tls/014-tls-h2-large-body-bio-park.phpt
@@ -48,7 +48,9 @@ register_shutdown_function(function () use ($tmp, $cert, $key) {
     @unlink($cert); @unlink($key); @rmdir($tmp);
 });
 
-$port = 19930 + getmypid() % 20;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $size = 256 * 1024;                       /* 8x the 32 KiB gather cap */
 $body = str_repeat("\0", $size);
 for ($i = 0; $i < $size; $i++) { $body[$i] = chr(($i * 31 + 7) & 0xff); }
diff --git a/tests/phpt/server/tls/015-tls-buffer-setter.phpt b/tests/phpt/server/tls/015-tls-buffer-setter.phpt
index 5a0d72d..b28ff4a 100644
--- a/tests/phpt/server/tls/015-tls-buffer-setter.phpt
+++ b/tests/phpt/server/tls/015-tls-buffer-setter.phpt
@@ -47,7 +47,9 @@ $key  = sys_get_temp_dir() . '/tls015-' . getmypid() . '.key';
 if (!tls_gen_cert($key, $cert)) { echo "cert gen failed\n"; exit(1); }
 register_shutdown_function(function () use ($cert, $key) { @unlink($cert); @unlink($key); });
 
-$port = 19945 + getmypid() % 20;
+require_once __DIR__ . '/../_free_port.inc';
+
+$port = tas_free_port();
 $size = 200000;                                            /* > one record → exercises park path */
 $body = str_repeat("\0", $size);
 for ($i = 0; $i < $size; $i++) { $body[$i] = chr(($i * 31 + 7) & 0xff); }
diff --git a/tests/phpt/websocket/005-handshake-101.phpt b/tests/phpt/websocket/005-handshake-101.phpt
index 26358cb..ad4f67f 100644
--- a/tests/phpt/websocket/005-handshake-101.phpt
+++ b/tests/phpt/websocket/005-handshake-101.phpt
@@ -12,8 +12,9 @@ use TrueAsync\HttpRequest;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19850 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/websocket/006-recv-text-frame.phpt b/tests/phpt/websocket/006-recv-text-frame.phpt
index 007737b..cd3bee7 100644
--- a/tests/phpt/websocket/006-recv-text-frame.phpt
+++ b/tests/phpt/websocket/006-recv-text-frame.phpt
@@ -13,8 +13,9 @@ use TrueAsync\HttpRequest;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19860 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/websocket/007-send-echo.phpt b/tests/phpt/websocket/007-send-echo.phpt
index 6386cc7..aee822c 100644
--- a/tests/phpt/websocket/007-send-echo.phpt
+++ b/tests/phpt/websocket/007-send-echo.phpt
@@ -12,8 +12,9 @@ use TrueAsync\HttpRequest;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19870 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/websocket/008-close-handshake.phpt b/tests/phpt/websocket/008-close-handshake.phpt
index 2e75b85..2ea9373 100644
--- a/tests/phpt/websocket/008-close-handshake.phpt
+++ b/tests/phpt/websocket/008-close-handshake.phpt
@@ -13,8 +13,9 @@ use TrueAsync\HttpRequest;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19880 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/websocket/009-binary-frames.phpt b/tests/phpt/websocket/009-binary-frames.phpt
index 14d5b0b..2a66d02 100644
--- a/tests/phpt/websocket/009-binary-frames.phpt
+++ b/tests/phpt/websocket/009-binary-frames.phpt
@@ -12,8 +12,9 @@ use TrueAsync\HttpRequest;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19890 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)->setWriteTimeout(5);
 $server = new HttpServer($config);
diff --git a/tests/phpt/websocket/010-fragmented-message.phpt b/tests/phpt/websocket/010-fragmented-message.phpt
index fc562e8..a2946c8 100644
--- a/tests/phpt/websocket/010-fragmented-message.phpt
+++ b/tests/phpt/websocket/010-fragmented-message.phpt
@@ -12,8 +12,9 @@ use TrueAsync\HttpRequest;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19900 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)->setWriteTimeout(5);
 $server = new HttpServer($config);
diff --git a/tests/phpt/websocket/011-concurrent-recv.phpt b/tests/phpt/websocket/011-concurrent-recv.phpt
index 5e2f66d..0e36db2 100644
--- a/tests/phpt/websocket/011-concurrent-recv.phpt
+++ b/tests/phpt/websocket/011-concurrent-recv.phpt
@@ -14,8 +14,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19910 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)->setWriteTimeout(5);
 $server = new HttpServer($config);
diff --git a/tests/phpt/websocket/012-upgrade-reject.phpt b/tests/phpt/websocket/012-upgrade-reject.phpt
index 4da5301..16a0500 100644
--- a/tests/phpt/websocket/012-upgrade-reject.phpt
+++ b/tests/phpt/websocket/012-upgrade-reject.phpt
@@ -13,8 +13,9 @@ use TrueAsync\HttpRequest;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19920 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)->setWriteTimeout(5);
 $server = new HttpServer($config);
diff --git a/tests/phpt/websocket/013-upgrade-subprotocol.phpt b/tests/phpt/websocket/013-upgrade-subprotocol.phpt
index 96dc8c7..bf601f2 100644
--- a/tests/phpt/websocket/013-upgrade-subprotocol.phpt
+++ b/tests/phpt/websocket/013-upgrade-subprotocol.phpt
@@ -13,8 +13,9 @@ use TrueAsync\HttpRequest;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19930 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)->setWriteTimeout(5);
 $server = new HttpServer($config);
diff --git a/tests/phpt/websocket/015-keepalive-ping.phpt b/tests/phpt/websocket/015-keepalive-ping.phpt
index a1bc423..86c41e8 100644
--- a/tests/phpt/websocket/015-keepalive-ping.phpt
+++ b/tests/phpt/websocket/015-keepalive-ping.phpt
@@ -13,8 +13,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19940 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/websocket/016-auto-pong.phpt b/tests/phpt/websocket/016-auto-pong.phpt
index b60b705..bc6d596 100644
--- a/tests/phpt/websocket/016-auto-pong.phpt
+++ b/tests/phpt/websocket/016-auto-pong.phpt
@@ -12,8 +12,9 @@ use TrueAsync\HttpRequest;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19960 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/websocket/017-remote-address.phpt b/tests/phpt/websocket/017-remote-address.phpt
index 1c440a8..a137e09 100644
--- a/tests/phpt/websocket/017-remote-address.phpt
+++ b/tests/phpt/websocket/017-remote-address.phpt
@@ -12,8 +12,9 @@ use TrueAsync\HttpRequest;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19980 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/websocket/018-wss-echo.phpt b/tests/phpt/websocket/018-wss-echo.phpt
index b74d660..4bfe666 100644
--- a/tests/phpt/websocket/018-wss-echo.phpt
+++ b/tests/phpt/websocket/018-wss-echo.phpt
@@ -52,8 +52,9 @@ echo "$status op=0x", dechex($op), " payload=$p\n";
 CLIENT
 );
 
-$port = 19920 + getmypid() % 30;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port, true)
     ->enableTls(true)
diff --git a/tests/phpt/websocket/019-h2-extended-connect.phpt b/tests/phpt/websocket/019-h2-extended-connect.phpt
index edddc02..59be653 100644
--- a/tests/phpt/websocket/019-h2-extended-connect.phpt
+++ b/tests/phpt/websocket/019-h2-extended-connect.phpt
@@ -13,8 +13,9 @@ use TrueAsync\HttpRequest;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19890 + getmypid() % 50;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(10)
diff --git a/tests/phpt/websocket/020-permessage-deflate-echo.phpt b/tests/phpt/websocket/020-permessage-deflate-echo.phpt
index 932f883..21a0a31 100644
--- a/tests/phpt/websocket/020-permessage-deflate-echo.phpt
+++ b/tests/phpt/websocket/020-permessage-deflate-echo.phpt
@@ -21,8 +21,9 @@ use TrueAsync\HttpRequest;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19880 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/websocket/021-permessage-deflate-bomb.phpt b/tests/phpt/websocket/021-permessage-deflate-bomb.phpt
index 866a03f..a91a06e 100644
--- a/tests/phpt/websocket/021-permessage-deflate-bomb.phpt
+++ b/tests/phpt/websocket/021-permessage-deflate-bomb.phpt
@@ -21,8 +21,9 @@ use TrueAsync\HttpRequest;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19890 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/websocket/022-h2-permessage-deflate.phpt b/tests/phpt/websocket/022-h2-permessage-deflate.phpt
index 6877d03..3b15c50 100644
--- a/tests/phpt/websocket/022-h2-permessage-deflate.phpt
+++ b/tests/phpt/websocket/022-h2-permessage-deflate.phpt
@@ -22,8 +22,9 @@ use TrueAsync\HttpRequest;
 use function Async\spawn;
 use function Async\await;
 
-$port = 19940 + getmypid() % 50;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(10)
diff --git a/tests/phpt/websocket/023-backpressure-trysend.phpt b/tests/phpt/websocket/023-backpressure-trysend.phpt
index b716279..fd0d03f 100644
--- a/tests/phpt/websocket/023-backpressure-trysend.phpt
+++ b/tests/phpt/websocket/023-backpressure-trysend.phpt
@@ -13,8 +13,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19990 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/websocket/024-backpressure-send-blocks.phpt b/tests/phpt/websocket/024-backpressure-send-blocks.phpt
index ee004cb..2ac6dac 100644
--- a/tests/phpt/websocket/024-backpressure-send-blocks.phpt
+++ b/tests/phpt/websocket/024-backpressure-send-blocks.phpt
@@ -13,8 +13,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19790 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/websocket/025-spawned-writer-teardown.phpt b/tests/phpt/websocket/025-spawned-writer-teardown.phpt
index 2e5cd18..607189e 100644
--- a/tests/phpt/websocket/025-spawned-writer-teardown.phpt
+++ b/tests/phpt/websocket/025-spawned-writer-teardown.phpt
@@ -32,7 +32,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19680 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
+
+$port = tas_free_port();
 $N    = 4;
 
 $config = (new HttpServerConfig())
diff --git a/tests/phpt/websocket/026-pong-timeout-close.phpt b/tests/phpt/websocket/026-pong-timeout-close.phpt
index 67839fc..e815de5 100644
--- a/tests/phpt/websocket/026-pong-timeout-close.phpt
+++ b/tests/phpt/websocket/026-pong-timeout-close.phpt
@@ -13,8 +13,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19960 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())
     ->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)
diff --git a/tests/phpt/websocket/027-handshake-bad-version.phpt b/tests/phpt/websocket/027-handshake-bad-version.phpt
index 9f71462..287d9a9 100644
--- a/tests/phpt/websocket/027-handshake-bad-version.phpt
+++ b/tests/phpt/websocket/027-handshake-bad-version.phpt
@@ -13,8 +13,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19970 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)->setWriteTimeout(5);
 $server = new HttpServer($config);
diff --git a/tests/phpt/websocket/028-handshake-missing-key.phpt b/tests/phpt/websocket/028-handshake-missing-key.phpt
index eea590b..62f99d4 100644
--- a/tests/phpt/websocket/028-handshake-missing-key.phpt
+++ b/tests/phpt/websocket/028-handshake-missing-key.phpt
@@ -13,8 +13,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19980 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)->setWriteTimeout(5);
 $server = new HttpServer($config);
diff --git a/tests/phpt/websocket/029-handshake-bad-method.phpt b/tests/phpt/websocket/029-handshake-bad-method.phpt
index 645aa65..81c4d3c 100644
--- a/tests/phpt/websocket/029-handshake-bad-method.phpt
+++ b/tests/phpt/websocket/029-handshake-bad-method.phpt
@@ -13,8 +13,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19990 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)->setWriteTimeout(5);
 $server = new HttpServer($config);
diff --git a/tests/phpt/websocket/030-utf8-failfast-teardown.phpt b/tests/phpt/websocket/030-utf8-failfast-teardown.phpt
index 1ac7883..a0461b5 100644
--- a/tests/phpt/websocket/030-utf8-failfast-teardown.phpt
+++ b/tests/phpt/websocket/030-utf8-failfast-teardown.phpt
@@ -19,8 +19,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19730 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)->setWriteTimeout(5);
 $server = new HttpServer($config);
diff --git a/tests/phpt/websocket/031-outbound-fragmentation.phpt b/tests/phpt/websocket/031-outbound-fragmentation.phpt
index 42d9f64..f15aef5 100644
--- a/tests/phpt/websocket/031-outbound-fragmentation.phpt
+++ b/tests/phpt/websocket/031-outbound-fragmentation.phpt
@@ -13,8 +13,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19740 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)->setWriteTimeout(5)
     ->setWsMaxFrameSize(128);   // cap each frame at 128 bytes (setter minimum)
diff --git a/tests/phpt/websocket/032-closed-exception-code.phpt b/tests/phpt/websocket/032-closed-exception-code.phpt
index 48e3aaa..d06a098 100644
--- a/tests/phpt/websocket/032-closed-exception-code.phpt
+++ b/tests/phpt/websocket/032-closed-exception-code.phpt
@@ -14,8 +14,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19750 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)->setWriteTimeout(5);
 $server = new HttpServer($config);
diff --git a/tests/phpt/websocket/033-foreach-iterator.phpt b/tests/phpt/websocket/033-foreach-iterator.phpt
index 1d4b01f..52676e9 100644
--- a/tests/phpt/websocket/033-foreach-iterator.phpt
+++ b/tests/phpt/websocket/033-foreach-iterator.phpt
@@ -13,8 +13,9 @@ use function Async\spawn;
 use function Async\await;
 use function Async\delay;
 
-$port = 19760 + getmypid() % 100;
+require_once __DIR__ . '/../server/_free_port.inc';
 
+$port = tas_free_port();
 $config = (new HttpServerConfig())->addListener('127.0.0.1', $port)
     ->setReadTimeout(5)->setWriteTimeout(5);
 $server = new HttpServer($config);