diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 32048b8..0d7a4d5 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -3,6 +3,8 @@ name: CI
 on:
   push:
     branches: [main]
+  pull_request:
+    branches: [main]
 
 permissions:
   contents: read
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
new file mode 100644
index 0000000..0dccdcf
--- /dev/null
+++ b/CONTRIBUTING.md
@@ -0,0 +1,99 @@
+# Contributing to SecGo
+
+Thanks for helping improve SecGo! This repo enforces a **PR-first** workflow and requires CI to pass before merging to `main`.
+
+---
+
+## ✅ Workflow Summary
+
+1. **Create a branch** off `main`.
+2. **Make changes locally**.
+3. **Run checks locally** (lint + tests).
+4. **Open a PR** into `main`.
+5. **Wait for CI** to pass and get at least **1 approval**.
+6. **Merge via PR** (no direct pushes to `main`).
+
+---
+
+## 🌿 Branch Naming
+
+Use a descriptive prefix:
+
+- `feature/<short-desc>` — new features
+- `fix/<short-desc>` — bug fixes
+- `chore/<short-desc>` — tooling, docs, refactors
+- `docs/<short-desc>` — documentation only
+
+Examples:
+- `feature/kiosk-scan-overlay`
+- `fix/manager-sync-timeout`
+- `chore/ci-main-only`
+
+---
+
+## 🧪 Local Checks
+
+Run these from the app folders before opening a PR:
+
+### Kiosk
+```bash
+cd Kiosk
+flutter pub get
+flutter analyze
+flutter test
+```
+
+### Manager
+```bash
+cd Manager
+flutter pub get
+flutter analyze
+flutter test
+```
+
+> Integration tests are optional locally (device required) but encouraged when touching user flows.
+
+---
+
+## 🧷 Environment Setup
+
+Use the provided templates:
+
+- `Kiosk/.env_template`
+- `Manager/.env_template`
+
+Copy to `.env` and fill values:
+```bash
+cp Kiosk/.env_template Kiosk/.env
+cp Manager/.env_template Manager/.env
+```
+
+---
+
+## ✅ PR Requirements
+
+- **At least 1 approval**
+- **CI passes** (lint + tests)
+- **No direct pushes** to `main`
+
+---
+
+## 🧾 Commit Style
+
+Keep commits small and meaningful. Suggested format:
+
+```
+<type>: <short summary>
+
+- bullet 1
+- bullet 2
+```
+
+Examples:
+- `feat: add kiosk pairing retry`
+- `fix: handle null barcode in scanner`
+- `chore: update ci workflow`
+
+---
+
+Thanks for contributing! 🙌