Lemme | arisjirat

Lemme is an AI-assisted quiz app. Users upload screenshots of quizzes; OCR extracts the question text, then multiple LLM providers generate candidate answers along with their reasoning.

Stack

Layer	Technology
Backend	Go 1.24, Fiber v2, MySQL, Redis, WebSocket, Google OAuth
Frontend	Solid.js, Vite, PandaCSS / Park UI, TypeScript
Reverse proxy / TLS	Caddy
Deployment target	Debian homelab at `lemme.arisjirat.com`

Architecture

Diagram arsitektur Lemme: Caddy di depan UI Nginx dan API Go Fiber

Browser
  -> Caddy (80/443, TLS termination)
      -> UI container (Nginx, static Solid build)
      -> API container (Go Fiber)
           -> MySQL (quiz/user/session data)
           -> Redis (session + OCR cache + locks)
           -> OCR + LLM providers (OpenAI/Anthropic/Gemini)

Caddy sits in front of the entire stack and handles TLS termination. Behind it:

UI — a static Solid build served by Nginx.
API — a Go Fiber service that talks to MySQL, Redis, and external OCR/LLM providers.

Local Development

Alur pengembangan lokal Lemme dengan Docker Compose

The whole stack runs via Docker Compose.

1. Configure the environment

Copy the root and backend env templates, then fill in the required secrets:

cp .env.example .env
cp lemme_service/.env.production.example lemme_service/.env

2. Start the services

make dev

3. Run migrations (if needed)

make migrate

4. Verify

Endpoint	URL
UI	`http://localhost:3000`
API health	`http://localhost:9090/healthz`

Production Deployment

1. Prepare the host

On the Debian server, run the setup script:

./scripts/setup-server.sh

2. Clone and configure

Clone the repository into /opt/lemme, then create the following env files:

/opt/lemme/.env
/opt/lemme/lemme_service/.env

3. Deploy

./deploy.sh

4. DNS and networking

Point the lemme.arisjirat.com A record at the host’s public IP, then forward ports 80 and 443.

5. TLS

Caddy provisions and renews certificates automatically — no manual steps required.

Environment Variables

Templates are available at:

.env.example — root compose env
lemme_service/.env.production.example — backend production env

Core variables

Group	Variables
Database	`MYSQL_ROOT_PASSWORD`, `MYSQL_DATABASE`, `MYSQL_USER`, `MYSQL_PASSWORD`
Redis	`REDIS_PASSWORD`
Backend	`DB_DSN`, `REDIS_ADDR`, `SESSION_COOKIE_SECRET`, `JWT_SECRET`
OAuth	`GOOGLE_CLIENT_ID`, `GOOGLE_CLIENT_SECRET`, `GOOGLE_REDIRECT_URL`
Frontend build args	`VITE_API_URL`, `VITE_WS_URL`, `VITE_FRONTEND_URL`, `VITE_FEEDBACK_GFORMS_URL`

Common Commands

make dev       # build + up
make up        # up without rebuild
make down      # stop all services
make build     # build all images
make migrate   # run DB migrations
make logs      # tail logs
make backup    # run backup script