deployments-cicd

SKILL.md

Vercel Deployments & CI/CD

You are an expert in Vercel deployment workflows — vercel deploy, vercel promote, vercel rollback, vercel inspect, vercel build, and CI/CD pipeline integration with GitHub Actions, GitLab CI, and Bitbucket Pipelines.

Deployment Commands

Preview Deployment

# Deploy from project root (creates preview URL)
vercel

# Equivalent explicit form
vercel deploy

Preview deployments are created automatically for every push to a non-production branch when using Git integration. They provide a unique URL for testing.

Production Deployment
# Deploy directly to production
vercel --prod
vercel deploy --prod

# Force a new deployment (skip cache)
vercel --prod --force

Build Locally, Deploy Build Output

# Build locally (uses development env vars by default)
vercel build

# Build with production env vars
vercel build --prod

# Deploy only the build output (no remote build)
vercel deploy --prebuilt
vercel deploy --prebuilt --prod

When to use --prebuilt: Custom CI pipelines where you control the build step, need build caching at the CI level, or need to run tests between build and deploy.

Promote & Rollback

# Promote a preview deployment to production
vercel promote <deployment-url-or-id>

# Rollback to the previous production deployment
vercel rollback

# Rollback to a specific deployment
vercel rollback <deployment-url-or-id>

Promote vs deploy --prod: promote is instant — it re-points the production alias without rebuilding. Use it when a preview deployment has been validated and is ready for production.

Inspect Deployments

# View deployment details (build info, functions, metadata)
vercel inspect <deployment-url>

# List recent deployments
vercel ls

# View logs for a deployment
vercel logs <deployment-url>
vercel logs <deployment-url> --follow

CI/CD Integration

Required Environment Variables

Every CI pipeline needs these three variables:

VERCEL_TOKEN=<your-token>        # Personal or team token
VERCEL_ORG_ID=<org-id>           # From .vercel/project.json
VERCEL_PROJECT_ID=<project-id>   # From .vercel/project.json

Set these as secrets in your CI provider. Never commit them to source control.

GitHub Actions

name: Deploy to Vercel
on:
  push:
    branches: [main]

jobs:
  deploy:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Install Vercel CLI
        run: npm install -g vercel

      - name: Pull Vercel Environment
        run: vercel pull --yes --environment=production --token=${{ secrets.VERCEL_TOKEN }}

      - name: Build
        run: vercel build --prod --token=${{ secrets.VERCEL_TOKEN }}

      - name: Deploy
        run: vercel deploy --prebuilt --prod --token=${{ secrets.VERCEL_TOKEN }}

OIDC Federation (Secure Backend Access)

Vercel OIDC federation is for secure backend access — letting your deployed Vercel functions authenticate with third-party services (AWS, GCP, HashiCorp Vault) without storing long-lived secrets. It does not replace VERCEL_TOKEN for CLI deployments.

What OIDC does: Your Vercel function requests a short-lived OIDC token from Vercel at runtime, then exchanges it with an external provider's STS/token endpoint for scoped credentials.

What OIDC does not do: Authenticate the Vercel CLI in CI pipelines. All vercel pull, vercel build, and vercel deploy commands still require --token=${{ secrets.VERCEL_TOKEN }}.

When to use OIDC:

Serverless functions that need to call AWS APIs (S3, DynamoDB, SQS)

Functions authenticating to GCP services via Workload Identity Federation

Any runtime service-to-service auth where you want to avoid storing static secrets in Vercel env vars

GitLab CI

deploy:
  image: node:20
  stage: deploy
  script:
    - npm install -g vercel
    - vercel pull --yes --environment=production --token=$VERCEL_TOKEN
    - vercel build --prod --token=$VERCEL_TOKEN
    - vercel deploy --prebuilt --prod --token=$VERCEL_TOKEN
  only:
    - main

Bitbucket Pipelines

pipelines:
  branches:
    main:
      - step:
          name: Deploy to Vercel
          image: node:20
          script:
            - npm install -g vercel
            - vercel pull --yes --environment=production --token=$VERCEL_TOKEN
            - vercel build --prod --token=$VERCEL_TOKEN
            - vercel deploy --prebuilt --prod --token=$VERCEL_TOKEN

Common CI Patterns

Preview Deployments on PRs

# GitHub Actions
on:
  pull_request:
    types: [opened, synchronize]

jobs:
  preview:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - run: npm install -g vercel
      - run: vercel pull --yes --environment=preview --token=${{ secrets.VERCEL_TOKEN }}
      - run: vercel build --token=${{ secrets.VERCEL_TOKEN }}
      - id: deploy
        run: echo "url=$(vercel deploy --prebuilt --token=${{ secrets.VERCEL_TOKEN }})" >> $GITHUB_OUTPUT
      - name: Comment PR
        uses: actions/github-script@v7
        with:
          script: |
            github.rest.issues.createComment({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
              body: `Preview: ${{ steps.deploy.outputs.url }}`
            })

Promote After Tests Pass

jobs:
  deploy-preview:
    # ... deploy preview ...
    outputs:
      url: ${{ steps.deploy.outputs.url }}

  e2e-tests:
    needs: deploy-preview
    runs-on: ubuntu-latest
    steps:
      - run: npx playwright test --base-url=${{ needs.deploy-preview.outputs.url }}

  promote:
    needs: [deploy-preview, e2e-tests]
    runs-on: ubuntu-latest
    if: github.ref == 'refs/heads/main'
    steps:
      - run: npm install -g vercel
      - run: vercel promote ${{ needs.deploy-preview.outputs.url }} --token=${{ secrets.VERCEL_TOKEN }}

Global CLI Flags for CI

Flag
Purpose

--token <token>
Authenticate (required in CI)

--yes / -y
Skip confirmation prompts

--scope <team>
Execute as a specific team

--cwd <dir>
Set working directory

Best Practices

Always use --prebuilt in CI — separates build from deploy, enables build caching and test gates

Use vercel pull before build — ensures correct env vars and project settings

Prefer promote over re-deploy — instant, no rebuild, same artifact

Use OIDC federation for runtime backend access — lets Vercel functions auth to AWS/GCP without static secrets (does not replace VERCEL_TOKEN for CLI)

Pin the Vercel CLI version in CI — npm install -g vercel@latest can break unexpectedly

Add --yes flag in CI — prevents interactive prompts from hanging pipelines

Deployment Strategy Matrix

Scenario
Strategy
Commands

Standard team workflow
Git-push deploy
Push to main/feature branches

Custom CI/CD (Actions, CircleCI)
Prebuilt deploy
vercel build && vercel deploy --prebuilt

Monorepo with Turborepo
Affected + remote cache
turbo run build --affected --remote-cache

Preview for every PR
Default behavior
Auto-creates preview URL per branch

Promote preview to production
CLI promotion
vercel promote <url>

Atomic deploys with DB migrations
Two-phase
Run migration → verify → vercel promote

Edge-first architecture
Edge Functions
Set runtime: 'edge' in route config

Common Build Errors

Error
Cause
Fix

ERR_PNPM_OUTDATED_LOCKFILE
Lockfile doesn't match package.json
Run pnpm install, commit lockfile

NEXT_NOT_FOUND
Root directory misconfigured
Set rootDirectory in Project Settings

Invalid next.config.js
Config syntax error
Validate config locally with next build

functions/api/*.js mismatch
Wrong file structure
Move to app/api/ directory (App Router)

Error: EPERM
File permission issue in build
Don't chmod in build scripts; use postinstall

Deploy Summary Format

Present a structured deploy result block:

## Deploy Result
- **URL**: <deployment-url>
- **Target**: production | preview
- **Status**: READY | ERROR | BUILDING | QUEUED
- **Commit**: <short-sha>
- **Framework**: <detected-framework>
- **Build Duration**: <duration>

If the deployment failed, append:

- **Error**: <summary of failure from logs>

For production deploys, also include:

### Post-Deploy Observability
- **Error scan**: <N errors found / clean> (scanned via vercel logs --level error --since 1h)
- **Drains**: <N configured / none>
- **Monitoring**: <active / gaps identified>

Deploy Next Steps

Based on the deployment outcome:

Success (preview) → "Visit the preview URL to verify. When ready, run /deploy prod to promote to production."

Success (production) → "Your production site is live. Run /status to see the full project overview."

Build error → "Check the build logs above. Common fixes: verify build script in package.json, check for missing env vars with /env list, ensure dependencies are installed."

Missing env vars → "Run /env pull to sync environment variables locally, or /env list to review what's configured on Vercel."

Monorepo issues → "Ensure the correct project root is configured in Vercel project settings. Check vercel.json for rootDirectory."

Post-deploy errors detected → "Review errors above. Check vercel logs <url> --level error for details. If drains are configured, correlate with external monitoring."

No monitoring configured → "Set up drains or install an error tracking integration before the next production deploy. Run /status for a full observability diagnostic."

Official Documentation

Deployments

Vercel CLI

GitHub Actions

GitLab CI

Bitbucket Pipelines

OIDC Federation