diff --git a/Makefile b/Makefile
index 731b6a7..c3226eb 100644
--- a/Makefile
+++ b/Makefile
@@ -8,10 +8,30 @@ endif
 
 include docker/.env
 
-# Current user ID and group ID except MacOS where it conflicts with Docker abilities
-ifeq ($(shell uname), Darwin)
+# Current user ID and group ID with platform-specific handling
+# Detect OS
+UNAME_S := $(shell uname -s 2>/dev/null || echo Unknown)
+IS_WSL := $(shell grep -qi microsoft /proc/version 2>/dev/null && echo 1 || echo 0)
+
+# MacOS: Use fixed UIDs to avoid conflicts with existing groups
+ifeq ($(UNAME_S),Darwin)
+    export UID=1000
+    export GID=1000
+# WSL (Windows Subsystem for Linux): Use fixed UIDs
+else ifeq ($(IS_WSL),1)
+    export UID=1000
+    export GID=1000
+# Windows (Git Bash/MSYS/MinGW/Cygwin): Use fixed UIDs
+else ifneq (,$(findstring MINGW,$(UNAME_S)))
+    export UID=1000
+    export GID=1000
+else ifneq (,$(findstring MSYS,$(UNAME_S)))
+    export UID=1000
+    export GID=1000
+else ifneq (,$(findstring CYGWIN,$(UNAME_S)))
     export UID=1000
     export GID=1000
+# Linux (native): Use current user's IDs
 else
     export UID=$(shell id -u)
     export GID=$(shell id -g)
diff --git a/docker/Dockerfile b/docker/Dockerfile
index 67445c3..f2c2bc8 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -38,12 +38,14 @@ COPY --from=composer /composer /usr/bin/composer
 
 # Based on https://frankenphp.dev/docs/docker/#running-as-a-non-root-user
 RUN \
-	groupadd --gid ${GROUP_ID} ${GROUP_NAME}; \
-    useradd --gid ${GROUP_ID} --uid ${USER_ID} ${GROUP_NAME}; \
+	# Create group if it doesn't exist (handles Mac GID 20 conflict) \
+	getent group ${GROUP_ID} || groupadd --gid ${GROUP_ID} ${GROUP_NAME}; \
+	# Create user \
+    useradd --gid ${GROUP_ID} --uid ${USER_ID} ${USER_NAME}; \
 	# Add additional capability to bind to port 80 and 443 \
 	setcap CAP_NET_BIND_SERVICE=+eip /usr/local/bin/frankenphp; \
-	# Give write access to /data/caddy and /config/caddy \
-	chown -R ${USER_NAME}:${GROUP_NAME} /data/caddy && chown -R ${USER_NAME}:${GROUP_NAME} /config/caddy
+	# Give write access to /data/caddy and /config/caddy (using GID for cross-platform compatibility) \
+	chown -R ${USER_NAME}:${GROUP_ID} /data/caddy && chown -R ${USER_NAME}:${GROUP_ID} /config/caddy
 USER ${USER_NAME}
 
 #