Gonstrukt

"Don't Roll Your Own Auth, They Said. They Also Said 'Just Use Firebase.' I Wrote Something Better."

Generate production-ready, GDPR-compliant authentication services in Go — in one command.

30 Seconds to Auth

# Install
go install github.com/DenisBytes/gonstrukt@latest

# Generate a complete auth service
gonstrukt create github.com/you/myauth \
  -s auth -d postgres -c yaml \
  --oauth google,apple --mfa \
  --gdpr consent,data-export,data-deletion

What you just got:

• JWT authentication with refresh tokens
• OAuth (Google, Apple) + MFA/TOTP with backup codes
• GDPR compliance: consent management, data export, right to erasure
• PostgreSQL with migrations
• OpenTelemetry tracing & metrics
• Production-ready security headers, rate limiting, TLS config

No Firebase. No Auth0 bills. No vendor lock-in. Just your code, your database, your users.

What Gets Generated

Authentication

• JWT access/refresh tokens with ECDSA signing
• Session management with device tracking
• Password hashing (bcrypt) with secure defaults
• Token blacklisting for logout/revocation

OAuth Providers

• Google, Microsoft, Apple Sign-In
• PKCE flow for security
• Automatic account linking

Multi-Factor Authentication

• TOTP with authenticator apps
• 10 backup codes (bcrypt hashed)
• Rate limiting (5 attempts → 15min lockout)

GDPR Compliance

• Versioned consent records with audit trail
• Data export (Article 20 - Portability)
• Account deletion with PII anonymization (Article 17)
• Processing logs with legal basis tracking

Security

• Secure headers (HSTS, CSP, X-Frame-Options)
• TLS 1.2+ with forward secrecy
• Request validation & rate limiting
• IP hashing for privacy

Observability

• OpenTelemetry traces & metrics
• Structured logging with Zap
• Health check endpoints

Optional Frontend

• React/Next.js/TanStack Start
• React Native Expo
• PostHog analytics, Sentry error tracking

Configuration

Service Types

-s gateway    # API gateway with rate limiting & caching
-s auth       # Authentication service
-s both       # Monorepo with both services

Databases

-d postgres   # PostgreSQL (recommended)
-d mysql      # MySQL
-d sqlite     # SQLite (dev/small projects)

Caching & Rate Limiting

--cache redis              # Redis or Valkey
--cache memory             # In-memory (dev only)
-r token-bucket            # Rate limiter algorithm
-r sliding-window

Auth Features

--oauth google,microsoft,apple   # OAuth providers
--mfa                            # TOTP multi-factor auth
--rbac                           # Role-based access control
--gdpr consent,data-export,data-deletion,processing-logs

Frontend (Optional)

--frontend web,mobile            # Generate frontend apps
--web-framework react            # react | next | tanstack
--ui-lib shadcn                  # shadcn | baseui
--state-mgmt tanstack            # tanstack | redux
--posthog --sentry               # Analytics & error tracking

Interactive Mode

Don't like flags? Just run:

gonstrukt create

A TUI wizard walks you through every option.

Project Structure (Generated)

myauth/
├── cmd/auth_service/    # Entry point
├── internals/
│   ├── services/        # Auth, OAuth, MFA, GDPR handlers
│   ├── middleware/      # JWT validation, rate limiting, security
│   ├── db/              # Database layer with migrations
│   └── telemetry/       # OpenTelemetry setup
├── config.yaml          # Configuration
├── Dockerfile
└── docker-compose.yml

Run It

cd myauth
cp config.yaml.example config.yaml  # Configure your secrets
docker-compose up -d                 # Start Postgres
go run ./cmd/auth_service            # Run the service

License

MIT — Do whatever you want. Roll your own auth. I dare you.

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Built by someone who got mass amounts of dopamine from making auth service generation trivial.