diff --git a/app/terminal/repl.tsx b/app/terminal/repl.tsx
index cc31d14..f1a9b46 100644
--- a/app/terminal/repl.tsx
+++ b/app/terminal/repl.tsx
@@ -17,8 +17,9 @@ import { useEmbedContext } from "./embedContext";
 import { emptyMutex, langConstants, RuntimeLang, useRuntime } from "./runtime";
 import clsx from "clsx";
 
+export type ReplOutputType = "stdout" | "stderr" | "error" | "return" | "trace" | "system";
 export interface ReplOutput {
-  type: "stdout" | "stderr" | "error" | "return" | "trace" | "system"; // 出力の種類
+  type: ReplOutputType; // 出力の種類
   message: string; // 出力メッセージ
 }
 export interface ReplCommand {
diff --git a/app/terminal/worker/jsEval.worker.ts b/app/terminal/worker/jsEval.worker.ts
index 1377410..64e2302 100644
--- a/app/terminal/worker/jsEval.worker.ts
+++ b/app/terminal/worker/jsEval.worker.ts
@@ -10,24 +10,20 @@ function format(...args: unknown[]): string {
   // https://nodejs.org/api/util.html#utilformatformat-args
   return args.map((a) => (typeof a === "string" ? a : inspect(a))).join(" ");
 }
-let jsOutput: ReplOutput[] = [];
+let currentOutputCallback: ((output: ReplOutput) => void) | null = null;
 
 // Helper function to capture console output
 const originalConsole = self.console;
 self.console = {
   ...originalConsole,
-  log: (...args: unknown[]) => {
-    jsOutput.push({ type: "stdout", message: format(...args) });
-  },
-  error: (...args: unknown[]) => {
-    jsOutput.push({ type: "stderr", message: format(...args) });
-  },
-  warn: (...args: unknown[]) => {
-    jsOutput.push({ type: "stderr", message: format(...args) });
-  },
-  info: (...args: unknown[]) => {
-    jsOutput.push({ type: "stdout", message: format(...args) });
-  },
+  log: (...args: unknown[]) =>
+    currentOutputCallback?.({ type: "stdout", message: format(...args) }),
+  error: (...args: unknown[]) =>
+    currentOutputCallback?.({ type: "stderr", message: format(...args) }),
+  warn: (...args: unknown[]) =>
+    currentOutputCallback?.({ type: "stderr", message: format(...args) }),
+  info: (...args: unknown[]) =>
+    currentOutputCallback?.({ type: "stdout", message: format(...args) }),
 };
 
 async function init(/*_interruptBuffer?: Uint8Array*/): Promise<{
@@ -73,13 +69,16 @@ async function replLikeEval(code: string): Promise<unknown> {
   }
 }
 
-async function runCode(code: string): Promise<{
-  output: ReplOutput[];
+async function runCode(
+  code: string,
+  onOutput: (output: ReplOutput) => void
+): Promise<{
   updatedFiles: Record<string, string>;
 }> {
+  currentOutputCallback = onOutput;
   try {
     const result = await replLikeEval(code);
-    jsOutput.push({
+    onOutput({
       type: "return",
       message: inspect(result),
     });
@@ -87,51 +86,51 @@ async function runCode(code: string): Promise<{
     originalConsole.log(e);
     // TODO: stack trace?
     if (e instanceof Error) {
-      jsOutput.push({
+      onOutput({
         type: "error",
         message: `${e.name}: ${e.message}`,
       });
     } else {
-      jsOutput.push({
+      onOutput({
         type: "error",
         message: `${String(e)}`,
       });
     }
+  } finally {
+    currentOutputCallback = null;
   }
 
-  const output = [...jsOutput];
-  jsOutput = []; // Clear output
-
-  return { output, updatedFiles: {} as Record<string, string> };
+  return { updatedFiles: {} as Record<string, string> };
 }
 
 function runFile(
   name: string,
-  files: Record<string, string>
-): { output: ReplOutput[]; updatedFiles: Record<string, string> } {
+  files: Record<string, string>,
+  onOutput: (output: ReplOutput) => void
+): { updatedFiles: Record<string, string> } {
   // pyodide worker などと異なり、複数ファイルを読み込んでimportのようなことをするのには対応していません。
+  currentOutputCallback = onOutput;
   try {
     self.eval(files[name]);
   } catch (e) {
     originalConsole.log(e);
     // TODO: stack trace?
     if (e instanceof Error) {
-      jsOutput.push({
+      onOutput({
         type: "error",
         message: `${e.name}: ${e.message}`,
       });
     } else {
-      jsOutput.push({
+      onOutput({
         type: "error",
         message: `${String(e)}`,
       });
     }
+  } finally {
+    currentOutputCallback = null;
   }
 
-  const output = [...jsOutput];
-  jsOutput = []; // Clear output
-
-  return { output, updatedFiles: {} as Record<string, string> };
+  return { updatedFiles: {} as Record<string, string> };
 }
 
 async function checkSyntax(
@@ -162,8 +161,6 @@ async function checkSyntax(
 
 async function restoreState(commands: string[]): Promise<object> {
   // Re-execute all previously successful commands to restore state
-  jsOutput = []; // Clear output for restoration
-
   for (const command of commands) {
     try {
       replLikeEval(command);
@@ -173,7 +170,6 @@ async function restoreState(commands: string[]): Promise<object> {
     }
   }
 
-  jsOutput = []; // Clear any output from restoration
   return {};
 }
 
diff --git a/app/terminal/worker/pyodide.worker.ts b/app/terminal/worker/pyodide.worker.ts
index e6cb985..fbfbe7e 100644
--- a/app/terminal/worker/pyodide.worker.ts
+++ b/app/terminal/worker/pyodide.worker.ts
@@ -16,7 +16,7 @@ const PYODIDE_CDN = `https://cdn.jsdelivr.net/pyodide/v${pyodideVersion}/full/`;
 const HOME = `/home/pyodide/`;
 
 let pyodide: PyodideInterface;
-let pyodideOutput: ReplOutput[] = [];
+let currentOutputCallback: ((output: ReplOutput) => void) | null = null;
 
 // Helper function to read all files from the Pyodide file system
 function readAllFiles(): Record<string, string> {
@@ -47,14 +47,12 @@ async function init(
     pyodide = await (self as any).loadPyodide({ indexURL: PYODIDE_CDN });
 
     pyodide.setStdout({
-      batched: (str: string) => {
-        pyodideOutput.push({ type: "stdout", message: str });
-      },
+      batched: (str: string) =>
+        currentOutputCallback?.({ type: "stdout", message: str }),
     });
     pyodide.setStderr({
-      batched: (str: string) => {
-        pyodideOutput.push({ type: "stderr", message: str });
-      },
+      batched: (str: string) =>
+        currentOutputCallback?.({ type: "stderr", message: str }),
     });
 
     pyodide.setInterruptBuffer(interruptBuffer);
@@ -62,17 +60,20 @@ async function init(
   return { capabilities: { interrupt: "buffer" } };
 }
 
-async function runCode(code: string): Promise<{
-  output: ReplOutput[];
+async function runCode(
+  code: string,
+  onOutput: (output: ReplOutput) => void
+): Promise<{
   updatedFiles: Record<string, string>;
 }> {
   if (!pyodide) {
     throw new Error("Pyodide not initialized");
   }
+  currentOutputCallback = onOutput;
   try {
     const result = await pyodide.runPythonAsync(code);
     if (result !== undefined) {
-      pyodideOutput.push({
+      onOutput({
         type: "return",
         message: String(result),
       });
@@ -86,7 +87,7 @@ async function runCode(code: string): Promise<{
         const execLineIndex = lines.findIndex((line) =>
           line.includes("<exec>")
         );
-        pyodideOutput.push({
+        onOutput({
           type: "error",
           message: lines
             .slice(0, 1)
@@ -95,33 +96,35 @@ async function runCode(code: string): Promise<{
             .trim(),
         });
       } else {
-        pyodideOutput.push({
+        onOutput({
           type: "error",
           message: `予期せぬエラー: ${e.message.trim()}`,
         });
       }
     } else {
-      pyodideOutput.push({
+      onOutput({
         type: "error",
         message: `予期せぬエラー: ${String(e).trim()}`,
       });
     }
+  } finally {
+    currentOutputCallback = null;
   }
 
   const updatedFiles = readAllFiles();
-  const output = [...pyodideOutput];
-  pyodideOutput = []; // 出力をクリア
 
-  return { output, updatedFiles };
+  return { updatedFiles };
 }
 
 async function runFile(
   name: string,
-  files: Record<string, string>
-): Promise<{ output: ReplOutput[]; updatedFiles: Record<string, string> }> {
+  files: Record<string, string>,
+  onOutput: (output: ReplOutput) => void
+): Promise<{ updatedFiles: Record<string, string> }> {
   if (!pyodide) {
     throw new Error("Pyodide not initialized");
   }
+  currentOutputCallback = onOutput;
   try {
     // Use Pyodide FS API to write files to the file system
     for (const filename of Object.keys(files)) {
@@ -142,7 +145,7 @@ async function runFile(
         const execLineIndex = lines.findLastIndex((line) =>
           line.includes("<exec>")
         );
-        pyodideOutput.push({
+        onOutput({
           type: "error",
           message: lines
             .slice(0, 1)
@@ -151,23 +154,23 @@ async function runFile(
             .trim(),
         });
       } else {
-        pyodideOutput.push({
+        onOutput({
           type: "error",
           message: `予期せぬエラー: ${e.message.trim()}`,
         });
       }
     } else {
-      pyodideOutput.push({
+      onOutput({
         type: "error",
         message: `予期せぬエラー: ${String(e).trim()}`,
       });
     }
+  } finally {
+    currentOutputCallback = null;
   }
 
   const updatedFiles = readAllFiles();
-  const output = [...pyodideOutput];
-  pyodideOutput = []; // 出力をクリア
-  return { output, updatedFiles };
+  return { updatedFiles };
 }
 
 async function checkSyntax(
diff --git a/app/terminal/worker/ruby.worker.ts b/app/terminal/worker/ruby.worker.ts
index ccc4a99..af6779d 100644
--- a/app/terminal/worker/ruby.worker.ts
+++ b/app/terminal/worker/ruby.worker.ts
@@ -5,12 +5,12 @@ import { expose } from "comlink";
 import { DefaultRubyVM } from "@ruby/wasm-wasi/dist/browser";
 import type { RubyVM } from "@ruby/wasm-wasi/dist/vm";
 import type { WorkerCapabilities } from "./runtime";
-import type { ReplOutput } from "../repl";
+import type { ReplOutput, ReplOutputType } from "../repl";
 
 import init_rb from "./ruby/init.rb?raw";
 
 let rubyVM: RubyVM | null = null;
-let rubyOutput: ReplOutput[] = [];
+let currentOutputCallback: ((output: ReplOutput) => void) | null = null;
 let stdoutBuffer = "";
 let stderrBuffer = "";
 
@@ -21,13 +21,26 @@ declare global {
 self.stdout = {
   write(str: string) {
     stdoutBuffer += str;
+    stdoutBuffer = handleBatchOutput(stdoutBuffer, "stdout");
   },
 };
 self.stderr = {
   write(str: string) {
     stderrBuffer += str;
+    stderrBuffer = handleBatchOutput(stderrBuffer, "stderr");
   },
 };
+function handleBatchOutput(buffer: string, type: ReplOutputType): string {
+  // If buffer contains newlines, flush complete lines immediately
+  if (buffer.includes("\n")) {
+    const lines = buffer.split("\n");
+    for (let i = 0; i < lines.length - 1; i++) {
+      currentOutputCallback?.({ type, message: lines[i] });
+    }
+    return lines[lines.length - 1];
+  }
+  return buffer;
+}
 
 async function init(/*_interruptBuffer?: Uint8Array*/): Promise<{
   capabilities: WorkerCapabilities;
@@ -55,28 +68,14 @@ async function init(/*_interruptBuffer?: Uint8Array*/): Promise<{
 }
 
 function flushOutput() {
-  if (stdoutBuffer) {
-    const lines = stdoutBuffer.split("\n");
-    for (let i = 0; i < lines.length - 1; i++) {
-      rubyOutput.push({ type: "stdout", message: lines[i] });
-    }
-    stdoutBuffer = lines[lines.length - 1];
-  }
-  // Final flush if there's remaining non-empty text
+  // Flush any remaining non-empty text without newlines
   if (stdoutBuffer && stdoutBuffer.trim()) {
-    rubyOutput.push({ type: "stdout", message: stdoutBuffer });
+    currentOutputCallback?.({ type: "stdout", message: stdoutBuffer });
   }
   stdoutBuffer = "";
 
-  if (stderrBuffer) {
-    const lines = stderrBuffer.split("\n");
-    for (let i = 0; i < lines.length - 1; i++) {
-      rubyOutput.push({ type: "stderr", message: lines[i] });
-    }
-    stderrBuffer = lines[lines.length - 1];
-  }
   if (stderrBuffer && stderrBuffer.trim()) {
-    rubyOutput.push({ type: "stderr", message: stderrBuffer });
+    currentOutputCallback?.({ type: "stderr", message: stderrBuffer });
   }
   stderrBuffer = "";
 }
@@ -101,58 +100,63 @@ function formatRubyError(error: unknown, isFile: boolean): string {
   return errorMessage;
 }
 
-async function runCode(code: string): Promise<{
-  output: ReplOutput[];
+async function runCode(
+  code: string,
+  onOutput: (output: ReplOutput) => void
+): Promise<{
   updatedFiles: Record<string, string>;
 }> {
   if (!rubyVM) {
     throw new Error("Ruby VM not initialized");
   }
 
+  currentOutputCallback = onOutput;
   try {
-    rubyOutput = [];
     stdoutBuffer = "";
     stderrBuffer = "";
 
     const result = rubyVM.eval(code);
 
+    const resultStr = await result.callAsync("inspect");
+
     // Flush any buffered output
     flushOutput();
 
-    const resultStr = await result.callAsync("inspect");
-
     // Add result to output if it's not nil and not empty
-    rubyOutput.push({
+    onOutput({
       type: "return",
       message: resultStr.toString(),
     });
   } catch (e) {
     console.log(e);
+
+    // Flush any buffered output
     flushOutput();
 
-    rubyOutput.push({
+    onOutput({
       type: "error",
       message: formatRubyError(e, false),
     });
+  } finally {
+    currentOutputCallback = null;
   }
 
   const updatedFiles = readAllFiles();
-  const output = [...rubyOutput];
-  rubyOutput = [];
 
-  return { output, updatedFiles };
+  return { updatedFiles };
 }
 
 async function runFile(
   name: string,
-  files: Record<string, string>
-): Promise<{ output: ReplOutput[]; updatedFiles: Record<string, string> }> {
+  files: Record<string, string>,
+  onOutput: (output: ReplOutput) => void
+): Promise<{ updatedFiles: Record<string, string> }> {
   if (!rubyVM) {
     throw new Error("Ruby VM not initialized");
   }
 
+  currentOutputCallback = onOutput;
   try {
-    rubyOutput = [];
     stdoutBuffer = "";
     stderrBuffer = "";
 
@@ -177,19 +181,21 @@ async function runFile(
     flushOutput();
   } catch (e) {
     console.log(e);
+
+    // Flush any buffered output
     flushOutput();
 
-    rubyOutput.push({
+    onOutput({
       type: "error",
       message: formatRubyError(e, true),
     });
+  } finally {
+    currentOutputCallback = null;
   }
 
   const updatedFiles = readAllFiles();
-  const output = [...rubyOutput];
-  rubyOutput = [];
 
-  return { output, updatedFiles };
+  return { updatedFiles };
 }
 
 async function checkSyntax(
@@ -266,7 +272,6 @@ async function restoreState(commands: string[]): Promise<object> {
     throw new Error("Ruby VM not initialized");
   }
 
-  rubyOutput = []; // Clear output for restoration
   stdoutBuffer = "";
   stderrBuffer = "";
 
@@ -279,9 +284,9 @@ async function restoreState(commands: string[]): Promise<object> {
     }
   }
 
-  // Clear any output from restoration
-  flushOutput();
-  rubyOutput = [];
+  // Clear any buffered output from restoration
+  stdoutBuffer = "";
+  stderrBuffer = "";
 
   return {};
 }
diff --git a/app/terminal/worker/runtime.tsx b/app/terminal/worker/runtime.tsx
index 99c2bf0..abc0291 100644
--- a/app/terminal/worker/runtime.tsx
+++ b/app/terminal/worker/runtime.tsx
@@ -9,7 +9,7 @@ import {
   useRef,
   useState,
 } from "react";
-import { wrap, Remote } from "comlink";
+import { wrap, Remote, proxy } from "comlink";
 import { RuntimeContext, RuntimeLang } from "../runtime";
 import { ReplOutput, SyntaxStatus } from "../repl";
 import { Mutex, MutexInterface } from "async-mutex";
@@ -26,12 +26,14 @@ export interface WorkerAPI {
     interruptBuffer: Uint8Array
   ): Promise<{ capabilities: WorkerCapabilities }>;
   runCode(
-    code: string
-  ): Promise<{ output: ReplOutput[]; updatedFiles: Record<string, string> }>;
+    code: string,
+    onOutput: (output: ReplOutput) => void
+  ): Promise<{ updatedFiles: Record<string, string> }>;
   runFile(
     name: string,
-    files: Record<string, string>
-  ): Promise<{ output: ReplOutput[]; updatedFiles: Record<string, string> }>;
+    files: Record<string, string>,
+    onOutput: (output: ReplOutput) => void
+  ): Promise<{ updatedFiles: Record<string, string> }>;
   checkSyntax(code: string): Promise<{ status: SyntaxStatus }>;
   restoreState(commands: string[]): Promise<object>;
 }
@@ -191,8 +193,14 @@ export function WorkerProvider({
       }
 
       try {
-        const { output, updatedFiles } = await trackPromise(
-          workerApiRef.current.runCode(code)
+        const output: ReplOutput[] = [];
+        const { updatedFiles } = await trackPromise(
+          workerApiRef.current.runCode(
+            code,
+            proxy((item: ReplOutput) => {
+              output.push(item);
+            })
+          )
         );
 
         writeFile(updatedFiles);
@@ -255,8 +263,15 @@ export function WorkerProvider({
         interruptBuffer.current[0] = 0;
       }
       return mutex.runExclusive(async () => {
-        const { output, updatedFiles } = await trackPromise(
-          workerApiRef.current!.runFile(filenames[0], files)
+        const output: ReplOutput[] = [];
+        const { updatedFiles } = await trackPromise(
+          workerApiRef.current!.runFile(
+            filenames[0],
+            files,
+            proxy((item: ReplOutput) => {
+              output.push(item);
+            })
+          )
         );
         writeFile(updatedFiles);
         return output;
diff --git a/package-lock.json b/package-lock.json
index 94e3088..f7bd4d7 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -40,7 +40,6 @@
         "remark-gfm": "^4.0.1",
         "remark-remove-comments": "^1.1.1",
         "swr": "^2.3.6",
-        "typescript": "^5.9.3",
         "zod": "^4.0.17"
       },
       "devDependencies": {
@@ -63,6 +62,7 @@
         "prisma": "^6.18.0",
         "tailwindcss": "^4",
         "tsx": "^4.20.6",
+        "typescript": "5.9.3",
         "wrangler": "^4.27.0"
       }
     },
diff --git a/package.json b/package.json
index 383b17c..0f7993c 100644
--- a/package.json
+++ b/package.json
@@ -48,7 +48,6 @@
     "remark-gfm": "^4.0.1",
     "remark-remove-comments": "^1.1.1",
     "swr": "^2.3.6",
-    "typescript": "^5.9.3",
     "zod": "^4.0.17"
   },
   "devDependencies": {
@@ -71,6 +70,7 @@
     "prisma": "^6.18.0",
     "tailwindcss": "^4",
     "tsx": "^4.20.6",
+    "typescript": "5.9.3",
     "wrangler": "^4.27.0"
   }
 }