
Github
- 128 installs
- 1.5k repo stars
- Updated July 20, 2026
- vercel-labs/emulate
Local GitHub REST API emulator for testing repos, issues, PRs, and webhooks.
About
Emulated GitHub REST API for local development and integration testing. Covers repositories, issues, pull requests, comments, and webhook events with in-memory persistence. Starts via npx emulate --service github. Enables testing GitHub App integrations, OAuth flows against localhost, and CI scripts that call GitHub API without rate limits or network dependency on github.com. Supports seed data for repos and issues and inspection of API state during test runs.
- Local GitHub REST API emulation for repos issues and PRs
- In-memory persistence for integration test isolation
- Webhook event simulation for GitHub App testing
- No github.com rate limits during local development
- Seed repos and issues for deterministic test scenarios
Github by the numbers
- 128 all-time installs (skills.sh)
- +6 installs in the week ending Jul 27, 2026 (Skillselion tracking)
- Ranked #928 of 2,153 Testing & QA skills by installs in the Skillselion catalog
- Security screen: HIGH risk (skills.sh audit)
- Data as of Aug 4, 2026 (Skillselion catalog sync)
github capabilities & compatibility
- Capabilities
- emulate github api · seed repos issues · simulate webhooks
- Works with
- github
- Use cases
- testing · api development
- Runs
- Runs locally
What github says it does
Emulated GitHub REST API for local development and testing.
npx skills add https://github.com/vercel-labs/emulate --skill githubAdd your badge
Show developers this skill is listed on Skillselion. Paste this into your README.
| Installs | 128 |
|---|---|
| repo stars | ★ 1.5k |
| Security audit | 2 / 3 scanners passed |
| Last updated | July 20, 2026 |
| Repository | vercel-labs/emulate ↗ |
How do I test GitHub API integrations locally?
Run emulated GitHub REST API locally to test repos, issues, PRs, and integrations without hitting github.com.
Who is it for?
Developers testing GitHub Apps, webhooks, or API integrations in CI.
Skip if: Real GitHub repository administration on github.com.
When should I use this skill?
User needs local GitHub API, test GitHub integrations, or emulate repos and issues.
What you get
GitHub REST calls hit local emulator with inspectable repo and issue state.
Files
GitHub API Emulator
Fully stateful GitHub REST API emulation. Creates, updates, and deletes persist in memory and affect related entities.
Start
# GitHub only
npx emulate --service github
# Default port
# http://localhost:4001Or programmatically:
import { createEmulator } from 'emulate'
const github = await createEmulator({ service: 'github', port: 4001 })
// github.url === 'http://localhost:4001'Auth
Pass tokens as Authorization: Bearer <token> or Authorization: token <token>.
curl http://localhost:4001/user \
-H "Authorization: Bearer test_token_admin"Public repo endpoints work without auth. Private repos and write operations require a valid token. When no token is provided, requests fall back to the first seeded user.
GitHub App JWT
Configure apps in the seed config with a private key. Sign a JWT with { iss: "<app_id>" } using RS256. The emulator verifies the signature and resolves the app.
github:
apps:
- app_id: 12345
slug: my-github-app
name: My GitHub App
private_key: |
-----BEGIN RSA PRIVATE KEY-----
...
-----END RSA PRIVATE KEY-----
permissions:
contents: read
issues: write
events: [push, pull_request]
webhook_url: http://localhost:8080/github/webhook
webhook_secret: my-webhook-secret
description: My CI/CD bot
installations:
- installation_id: 100
account: my-org
repository_selection: all
permissions:
contents: read
events: [push]
repositories: [my-org/org-repo]Pointing Your App at the Emulator
Environment Variable
GITHUB_EMULATOR_URL=http://localhost:4001Octokit
import { Octokit } from '@octokit/rest'
const octokit = new Octokit({
baseUrl: process.env.GITHUB_EMULATOR_URL ?? 'https://api.github.com',
auth: 'test_token_admin',
})OAuth URL Mapping
| Real GitHub URL | Emulator URL |
|---|---|
https://github.com/login/oauth/authorize | $GITHUB_EMULATOR_URL/login/oauth/authorize |
https://github.com/login/oauth/access_token | $GITHUB_EMULATOR_URL/login/oauth/access_token |
https://api.github.com/user | $GITHUB_EMULATOR_URL/user |
Auth.js / NextAuth.js
import GitHub from '@auth/core/providers/github'
GitHub({
clientId: process.env.GITHUB_CLIENT_ID,
clientSecret: process.env.GITHUB_CLIENT_SECRET,
authorization: {
url: `${process.env.GITHUB_EMULATOR_URL}/login/oauth/authorize`,
},
token: {
url: `${process.env.GITHUB_EMULATOR_URL}/login/oauth/access_token`,
},
userinfo: {
url: `${process.env.GITHUB_EMULATOR_URL}/user`,
},
})Seed Config
tokens:
test_token_admin:
login: admin
scopes: [repo, user, admin:org, admin:repo_hook]
github:
users:
- login: octocat
name: The Octocat
email: octocat@github.com
bio: I am the Octocat
company: GitHub
location: San Francisco
blog: https://github.blog
twitter_username: github
site_admin: false
orgs:
- login: my-org
name: My Organization
description: A test organization
email: org@example.com
repos:
- owner: octocat
name: hello-world
description: My first repository
language: JavaScript
topics: [hello, world]
default_branch: main
private: false
- owner: my-org
name: org-repo
description: An organization repository
language: TypeScript
oauth_apps:
- client_id: Iv1.abc123
client_secret: secret_abc123
name: My Web App
redirect_uris:
- http://localhost:3000/api/auth/callback/githubRepos are auto-initialized with a commit, branch, and README unless auto_init: false is set.
Pagination
All list endpoints support page and per_page query params with Link headers:
curl "http://localhost:4001/repos/octocat/hello-world/issues?page=1&per_page=10" \
-H "Authorization: Bearer $TOKEN"API Endpoints
Users
# Authenticated user
curl http://localhost:4001/user -H "Authorization: Bearer $TOKEN"
# Update profile
curl -X PATCH http://localhost:4001/user \
-H "Authorization: Bearer $TOKEN" \
-H "Content-Type: application/json" \
-d '{"bio": "Hello!"}'
# Get user by username
curl http://localhost:4001/users/octocat
# List users
curl http://localhost:4001/users
# User repos / orgs / followers / following
curl http://localhost:4001/users/octocat/repos
curl http://localhost:4001/users/octocat/orgs
curl http://localhost:4001/users/octocat/followers
curl http://localhost:4001/users/octocat/following
# User hovercard
curl http://localhost:4001/users/octocat/hovercard
# User emails
curl http://localhost:4001/user/emails -H "Authorization: Bearer $TOKEN"Repositories
# Get repo
curl http://localhost:4001/repos/octocat/hello-world
# Create user repo
curl -X POST http://localhost:4001/user/repos \
-H "Authorization: Bearer $TOKEN" \
-H "Content-Type: application/json" \
-d '{"name": "new-repo", "private": false}'
# Create org repo
curl -X POST http://localhost:4001/orgs/my-org/repos \
-H "Authorization: Bearer $TOKEN" \
-H "Content-Type: application/json" \
-d '{"name": "org-project"}'
# Update repo
curl -X PATCH http://localhost:4001/repos/octocat/hello-world \
-H "Authorization: Bearer $TOKEN" \
-H "Content-Type: application/json" \
-d '{"description": "Updated description"}'
# Delete repo (cascades issues, PRs, etc.)
curl -X DELETE http://localhost:4001/repos/octocat/hello-world \
-H "Authorization: Bearer $TOKEN"
# Topics, languages, contributors, forks, collaborators, tags, transferIssues
# List issues (filter by state, labels, assignee, milestone, creator, since)
curl "http://localhost:4001/repos/octocat/hello-world/issues?state=open&labels=bug"
# Create issue
curl -X POST http://localhost:4001/repos/octocat/hello-world/issues \
-H "Authorization: Bearer $TOKEN" \
-H "Content-Type: application/json" \
-d '{"title": "Bug report", "body": "Details here", "labels": ["bug"]}'
# Get / update / lock / unlock / timeline / events / assigneesPull Requests
# List PRs
curl "http://localhost:4001/repos/octocat/hello-world/pulls?state=open"
# Create PR
curl -X POST http://localhost:4001/repos/octocat/hello-world/pulls \
-H "Authorization: Bearer $TOKEN" \
-H "Content-Type: application/json" \
-d '{"title": "Feature", "head": "feature-branch", "base": "main"}'
# Merge PR (enforces branch protection)
curl -X PUT http://localhost:4001/repos/octocat/hello-world/pulls/1/merge \
-H "Authorization: Bearer $TOKEN" \
-H "Content-Type: application/json" \
-d '{"merge_method": "squash"}'
# Commits, files, requested reviewers, update branchComments
# Issue comments: full CRUD
curl http://localhost:4001/repos/octocat/hello-world/issues/1/comments
curl -X POST http://localhost:4001/repos/octocat/hello-world/issues/1/comments \
-H "Authorization: Bearer $TOKEN" \
-H "Content-Type: application/json" \
-d '{"body": "Looks good!"}'
# Comment by ID (cross-resource)
curl http://localhost:4001/repos/octocat/hello-world/issues/comments/1
# PR review comments
curl http://localhost:4001/repos/octocat/hello-world/pulls/1/comments
# Commit comments
curl http://localhost:4001/repos/octocat/hello-world/commits/abc123/comments
# Repo-wide comment listings
curl http://localhost:4001/repos/octocat/hello-world/issues/comments
curl http://localhost:4001/repos/octocat/hello-world/pulls/comments
curl http://localhost:4001/repos/octocat/hello-world/commentsReviews
# List / create / get / update / submit / dismiss reviews
curl http://localhost:4001/repos/octocat/hello-world/pulls/1/reviews
curl -X POST http://localhost:4001/repos/octocat/hello-world/pulls/1/reviews \
-H "Authorization: Bearer $TOKEN" \
-H "Content-Type: application/json" \
-d '{"event": "APPROVE", "body": "LGTM"}'Labels & Milestones
Full CRUD for labels and milestones. Add/remove labels from issues, replace all labels. List labels for a milestone.
Branches & Git Data
# List branches
curl http://localhost:4001/repos/octocat/hello-world/branches
# Branch protection CRUD (status checks, PR reviews, enforce admins)
curl -X PUT http://localhost:4001/repos/octocat/hello-world/branches/main/protection \
-H "Authorization: Bearer $TOKEN" \
-H "Content-Type: application/json" \
-d '{"required_status_checks": {"strict": true, "contexts": ["ci"]}}'
# Refs, commits, trees (recursive), blobs, tags, matching-refsOrganizations & Teams
# List all orgs / user's orgs / get org / update org
curl http://localhost:4001/organizations
curl http://localhost:4001/user/orgs -H "Authorization: Bearer $TOKEN"
curl http://localhost:4001/orgs/my-org
curl -X PATCH http://localhost:4001/orgs/my-org \
-H "Authorization: Bearer $TOKEN" \
-H "Content-Type: application/json" \
-d '{"description": "Updated org"}'
# Org members: list, get, remove
curl http://localhost:4001/orgs/my-org/members
curl http://localhost:4001/orgs/my-org/members/octocat
curl -X DELETE http://localhost:4001/orgs/my-org/members/octocat \
-H "Authorization: Bearer $TOKEN"
# Org memberships: get, set (invite/update role)
curl http://localhost:4001/orgs/my-org/memberships/octocat -H "Authorization: Bearer $TOKEN"
curl -X PUT http://localhost:4001/orgs/my-org/memberships/octocat \
-H "Authorization: Bearer $TOKEN" \
-H "Content-Type: application/json" \
-d '{"role": "admin"}'
# Teams: CRUD
curl http://localhost:4001/orgs/my-org/teams
curl -X POST http://localhost:4001/orgs/my-org/teams \
-H "Authorization: Bearer $TOKEN" \
-H "Content-Type: application/json" \
-d '{"name": "engineering", "privacy": "closed"}'
# Team members and memberships
curl http://localhost:4001/orgs/my-org/teams/engineering/members
curl -X PUT http://localhost:4001/orgs/my-org/teams/engineering/memberships/octocat \
-H "Authorization: Bearer $TOKEN" \
-H "Content-Type: application/json" \
-d '{"role": "maintainer"}'
# Team repos: list, add, remove
curl http://localhost:4001/orgs/my-org/teams/engineering/repos
curl -X PUT http://localhost:4001/orgs/my-org/teams/engineering/repos/my-org/org-repo \
-H "Authorization: Bearer $TOKEN"
# Legacy team endpoints by ID
curl http://localhost:4001/teams/1
curl http://localhost:4001/teams/1/membersGitHub Apps
# Get authenticated app (requires JWT auth)
curl http://localhost:4001/app \
-H "Authorization: Bearer <jwt>"
# List app installations
curl http://localhost:4001/app/installations \
-H "Authorization: Bearer <jwt>"
# Get installation
curl http://localhost:4001/app/installations/100 \
-H "Authorization: Bearer <jwt>"
# Create installation access token (mints ghs_... token)
curl -X POST http://localhost:4001/app/installations/100/access_tokens \
-H "Authorization: Bearer <jwt>" \
-H "Content-Type: application/json" \
-d '{"permissions": {"contents": "read"}}'
# Find installation for repo / org / user
curl http://localhost:4001/repos/my-org/org-repo/installation
curl http://localhost:4001/orgs/my-org/installation
curl http://localhost:4001/users/octocat/installationApp webhook delivery: when events occur, the emulator POSTs event_callback payloads to configured webhook_url with X-GitHub-Event and X-Hub-Signature-256 headers.
Releases
# Create release
curl -X POST http://localhost:4001/repos/octocat/hello-world/releases \
-H "Authorization: Bearer $TOKEN" \
-H "Content-Type: application/json" \
-d '{"tag_name": "v1.0.0", "name": "v1.0.0"}'
# List, get, latest, by tag, generate notes
# Release assets: list, upload
curl http://localhost:4001/repos/octocat/hello-world/releases/1/assets
curl -X POST http://localhost:4001/repos/octocat/hello-world/releases/1/assets \
-H "Authorization: Bearer $TOKEN" \
-H "Content-Type: application/octet-stream" \
-H "name: binary.zip" \
--data-binary @binary.zipWebhooks
# Create webhook (real HTTP delivery on state changes)
curl -X POST http://localhost:4001/repos/octocat/hello-world/hooks \
-H "Authorization: Bearer $TOKEN" \
-H "Content-Type: application/json" \
-d '{"config": {"url": "http://localhost:8080/webhook"}, "events": ["push", "pull_request"]}'
# Full CRUD, ping, test, deliveries
# Org webhooks also supportedSearch
# Search repositories
curl "http://localhost:4001/search/repositories?q=language:JavaScript+user:octocat"
# Search issues and PRs
curl "http://localhost:4001/search/issues?q=repo:octocat/hello-world+is:open"
# Search users, code, commits, topics, labelsActions
# Workflows: list, get, enable/disable, dispatch
# Workflow runs: list, get, cancel, rerun, delete, logs
# Jobs: list, get, logs
# Artifacts: list, get, delete
# Secrets: repo + org CRUDChecks
# Create check run
curl -X POST http://localhost:4001/repos/octocat/hello-world/check-runs \
-H "Authorization: Bearer $TOKEN" \
-H "Content-Type: application/json" \
-d '{"name": "CI", "head_sha": "abc123", "status": "completed", "conclusion": "success"}'
# Check suites: create, get, rerequest, preferences, list by ref
# Check runs: list for suite, annotations
# Automatic suite status rollup from check run resultsOAuth
# Authorize (browser flow, shows user picker)
# GET /login/oauth/authorize?client_id=...&redirect_uri=...&scope=...&state=...
# Token exchange
curl -X POST http://localhost:4001/login/oauth/access_token \
-H "Content-Type: application/json" \
-H "Accept: application/json" \
-d '{"client_id": "Iv1.abc123", "client_secret": "secret_abc123", "code": "<code>"}'
# User emails
curl http://localhost:4001/user/emails -H "Authorization: Bearer $TOKEN"
# OAuth app management (settings)
curl http://localhost:4001/settings/applications -H "Authorization: Bearer $TOKEN"
curl http://localhost:4001/settings/connections/applications/Iv1.abc123 -H "Authorization: Bearer $TOKEN"
# Revoke OAuth app
curl -X POST http://localhost:4001/settings/connections/applications/Iv1.abc123/revoke \
-H "Authorization: Bearer $TOKEN"Misc
curl http://localhost:4001/rate_limit
curl http://localhost:4001/meta
curl http://localhost:4001/emojis
curl http://localhost:4001/versions
curl http://localhost:4001/octocat
curl http://localhost:4001/zenCommon Patterns
Create Repo, Issue, and PR
TOKEN="test_token_admin"
BASE="http://localhost:4001"
# Create repo
curl -X POST $BASE/user/repos \
-H "Authorization: Bearer $TOKEN" \
-H "Content-Type: application/json" \
-d '{"name": "my-project"}'
# Create issue
curl -X POST $BASE/repos/admin/my-project/issues \
-H "Authorization: Bearer $TOKEN" \
-H "Content-Type: application/json" \
-d '{"title": "First issue"}'
# Create PR
curl -X POST $BASE/repos/admin/my-project/pulls \
-H "Authorization: Bearer $TOKEN" \
-H "Content-Type: application/json" \
-d '{"title": "First PR", "head": "feature", "base": "main"}'GitHub App Installation Token Flow
# 1. Sign a JWT with { iss: "12345" } using the app's private key (RS256)
# 2. Create an installation access token
curl -X POST $BASE/app/installations/100/access_tokens \
-H "Authorization: Bearer <jwt>" \
-H "Content-Type: application/json" \
-d '{"permissions": {"contents": "read", "issues": "write"}}'
# Returns { "token": "ghs_...", ... }
# 3. Use the installation token to call API endpoints
curl $BASE/repos/my-org/org-repo \
-H "Authorization: Bearer ghs_..."OAuth Flow
1. Redirect user to $GITHUB_EMULATOR_URL/login/oauth/authorize?client_id=...&redirect_uri=...&scope=user+repo&state=... 2. User picks a seeded user on the emulator's UI 3. Emulator redirects back with ?code=...&state=... 4. Exchange code for token via POST /login/oauth/access_token 5. Use token to call API endpoints
Related skills
FAQ
What GitHub resources are emulated?
Repositories, issues, pull requests, comments, and webhook events.
How do I start the emulator?
npx emulate --service github following the emulate family pattern.
Can I seed test data?
Yes. Seed configuration supports repos and issues for deterministic tests.
Is Github safe to install?
skills.sh reports 2 of 3 security scanners passed. Review the Security Audits panel on this page before installing in production.