diff --git a/.github/workflows/check.yaml b/.github/workflows/check.yaml
index 30bf51ed..e4e221bc 100644
--- a/.github/workflows/check.yaml
+++ b/.github/workflows/check.yaml
@@ -5,6 +5,22 @@ name: Check
 on:
     pull_request:
     workflow_call:
+        inputs:
+            bun_e2e_mode:
+                description: 'Bun e2e suite scope: `compatible` (curated subset known to pass) or `full` (entire suite).'
+                type: string
+                default: compatible
+                required: false
+    workflow_dispatch:
+        inputs:
+            bun_e2e_mode:
+                description: 'Bun e2e suite scope'
+                type: choice
+                options:
+                    - compatible
+                    - full
+                default: compatible
+                required: true
 
 jobs:
     lint:
@@ -53,7 +69,7 @@ jobs:
               run: npm run test:unit
 
     e2e:
-        name: E2E tests
+        name: E2E tests (Node.js 24)
         if: ${{ !contains(github.event.head_commit.message, '[skip ci]') }}
         runs-on: ubuntu-24.04
 
@@ -74,3 +90,58 @@ jobs:
 
             - name: Run E2E tests
               run: npm run test:e2e
+
+    bun_unit:
+        name: Unit tests (Bun)
+        if: ${{ !contains(github.event.head_commit.message, '[skip ci]') }}
+        runs-on: ubuntu-24.04
+        timeout-minutes: 15
+
+        steps:
+            - name: Checkout repository
+              uses: actions/checkout@v6
+
+            - name: Use Node.js 24
+              uses: actions/setup-node@v6
+              with:
+                  node-version: 24
+
+            - name: Install Bun
+              uses: oven-sh/setup-bun@v2
+              with:
+                  bun-version: latest
+
+            - name: Install Dependencies
+              run: npm install
+
+            - name: Run unit tests with Bun
+              run: npm run test:bun
+
+    bun_e2e:
+        name: E2E tests (Bun, ${{ inputs.bun_e2e_mode || 'compatible' }})
+        if: ${{ !contains(github.event.head_commit.message, '[skip ci]') }}
+        runs-on: ubuntu-24.04
+        timeout-minutes: 30
+
+        steps:
+            - name: Checkout repository
+              uses: actions/checkout@v6
+
+            - name: Use Node.js 24
+              uses: actions/setup-node@v6
+              with:
+                  node-version: 24
+
+            - name: Install Bun
+              uses: oven-sh/setup-bun@v2
+              with:
+                  bun-version: latest
+
+            - name: Install Dependencies
+              run: npm install
+
+            - name: Add localhost-test to Linux hosts file
+              run: sudo echo "127.0.0.1 localhost-test" | sudo tee -a /etc/hosts
+
+            - name: Run E2E tests (Bun, ${{ inputs.bun_e2e_mode || 'compatible' }})
+              run: npm run test:bun:e2e:${{ inputs.bun_e2e_mode || 'compatible' }}
diff --git a/package.json b/package.json
index 472fe551..d5873ba0 100644
--- a/package.json
+++ b/package.json
@@ -47,6 +47,9 @@
         "test": "nyc cross-env NODE_OPTIONS=--insecure-http-parser mocha 'test/unit/**/*.js' 'test/e2e/**/*.js'",
         "test:unit": "mocha 'test/unit/**/*.js'",
         "test:e2e": "nyc cross-env NODE_OPTIONS=--insecure-http-parser mocha 'test/e2e/**/*.js'",
+        "test:bun": "bun --bun run mocha --no-config --exit 'test/unit/**/*.js'",
+        "test:bun:e2e:compatible": "bun --bun run mocha --no-config --exit --grep 'throws error' test/e2e/tcp_tunnel.js",
+        "test:bun:e2e:full": "bun --bun run mocha --no-config --exit 'test/e2e/**/*.js'",
         "test:docker": "docker build --tag proxy-chain-tests --file test/Dockerfile . && docker run --add-host localhost-test:127.0.0.1 proxy-chain-tests",
         "test:docker:all": "bash scripts/test-docker-all.sh",
         "lint": "eslint .",
diff --git a/test/README.md b/test/README.md
index b96f4b71..4b72a7c7 100644
--- a/test/README.md
+++ b/test/README.md
@@ -80,3 +80,33 @@ Note: for test in Docker no changes in `/etc/hosts` needed.
     ```bash
     npm test test/e2e/anonymize_proxy.js
     ```
+
+### Run tests with Bun
+
+[Bun](https://bun.com) is supported as an alternative runtime. Install it from
+https://bun.com, then run:
+
+```bash
+# Unit tests (always green on Bun, gates every PR)
+npm run test:bun
+
+# E2E tests — curated subset known to pass on Bun
+npm run test:bun:e2e:compatible
+
+# E2E tests — entire suite (some tests rely on Node-only HTTP semantics
+# such as HTTP/1.1 pipelining and stream.pipeline behaviour that current
+# Bun releases don't fully emulate; expect failures)
+npm run test:bun:e2e:full
+```
+
+In CI, `bun_unit` and `bun_e2e` (in `compatible` mode) run on every PR.
+The full Bun e2e suite is opt-in: trigger the **Check** workflow via
+**Actions → Check → Run workflow** and pick `full` for the
+`bun_e2e_mode` input.
+
+The `compatible` subset is intentionally narrow today — it only runs the
+URL-validation tests in `test/e2e/tcp_tunnel.js` (via `--grep 'throws
+error'`), which exercise `createTunnel`'s error paths without touching
+the network. As individual networked tests are confirmed to pass on
+Bun, widen the `test:bun:e2e:compatible` script in `package.json` (drop
+the `--grep`, add files, or list specific test names).