Deployment Guide

Production deployment paths, environment variables, networking and operations for NextJudge at scale.

Local setup: Getting started. Environment and OAuth detail: Configuration.

Pick your deploy path

Method	When	Command / file
deploy.sh	First prod-like test on a VM	`./deploy.sh web`
Prebuilt images	Production without local build	`docker compose -f compose/docker-compose.prebuilt.yml up -d`
docker buildx bake	Fresh images after code changes	`docker buildx bake -f docker-bake.hcl`
Coolify	Coolify-managed host	`compose/docker-compose.coolify.yml`

Build images on development machines or in CI. Pull prebuilt images on production hosts to avoid compiling Go and judge toolchains during deploy windows.

Environment variables

See Configuration for the full matrix. Summary:

Data layer (required)

DB_PASSWORD, JWT_SIGNING_SECRET, JUDGE_PASSWORD, WEB_BRIDGE_SECRET, RABBITMQ_USER, RABBITMQ_PASSWORD

Data layer (production)

Variable	Notes
`CORS_ORIGIN`	Web origin(s), comma-separated; no wildcards
`CORS_ALLOW_PREVIEW`	`true` for Coolify PR previews
`TRUSTED_PROXY`	`true` when the API sits behind Coolify Traefik or another reverse proxy
`PASSWORD_RESET_DEBUG`	`false` in prod (dev/E2E only)
`ALLOW_INSECURE_PASSWORD_RESET`	`false` in prod (dev only)
`ADMIN_EMAILS`	Admin bootstrap emails
`SEED_DATA`	`false` in prod
`ELASTIC_ENABLED`	`true` only if Elasticsearch is deployed
`CORS_ALLOW_PREVIEW`	`true` for Coolify PR previews

Web (build-time + runtime)

NEXT_PUBLIC_API_URL, AUTH_SECRET, NEXTAUTH_URL, WEB_BRIDGE_SECRET, AUTH_GITHUB_ID, AUTH_GITHUB_SECRET

Generate backend secrets: ./.createenv.sh > .env

Network layout

Internet → TLS proxy → web :8080
                         ↓ (internal)
                    data layer :5000
                         ↓
              Postgres, RabbitMQ (never public)
                         ↑
                    judge workers (internal only)

Block 5432, 5672 from the public internet. Expose 443 to users. The API (5000) should be reachable from the web app and judges — typically internal or a separate api. subdomain, not open to arbitrary clients without rate limiting.

TLS proxy (nginx sketch)

Web app

server {
    listen 443 ssl;
    server_name nextjudge.example.com;
    ssl_certificate     /etc/letsencrypt/live/nextjudge.example.com/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/nextjudge.example.com/privkey.pem;

    location / {
        proxy_pass http://127.0.0.1:8080;
        proxy_set_header Host $host;
        proxy_set_header X-Forwarded-Proto $scheme;
    }
}

Set NEXTAUTH_URL=https://nextjudge.example.com.

API (optional separate subdomain)

server {
    listen 443 ssl;
    server_name api.nextjudge.example.com;
    ssl_certificate     /etc/letsencrypt/live/api.nextjudge.example.com/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/api.nextjudge.example.com/privkey.pem;

    location / {
        proxy_pass http://127.0.0.1:5000;
        proxy_set_header Host $host;
        proxy_set_header X-Forwarded-Proto $scheme;
    }
}

Set NEXT_PUBLIC_API_URL=https://api.nextjudge.example.com at web build time. Set CORS_ORIGIN=https://nextjudge.example.com on the data layer. Set TRUSTED_PROXY=true on the data layer so rate limits use the client IP from X-Forwarded-For.

Coolify

Deploy the backend with compose/docker-compose.coolify.yml:

Images: ${DOCKERHUB_NAMESPACE}/nextjudge-core:latest, ${DOCKERHUB_NAMESPACE}/nextjudge-judge:latest (default namespace: nextjudge)
Data layer uses expose: 5000 — route via Coolify proxy to your API domain
Does not include web or Elasticsearch

Deploy web as a separate Coolify application from src/web. Required build env: NEXT_PUBLIC_API_URL, AUTH_SECRET, NEXTAUTH_URL, WEB_BRIDGE_SECRET, GitHub OAuth vars.

Backend Coolify env: same secrets as Configuration — Coolify.

PR previews: CI deploys {PR}-web, {PR}-docs via Coolify application previews and {PR}-api via SSH (scripts/coolify-preview-backend-ssh.sh). Set CORS_ALLOW_PREVIEW=true on the production backend service. Preview web omits NEXT_PUBLIC_API_URL; GitHub OAuth uses the production redirect proxy. Details: Configuration — PR previews.

Elasticsearch (optional)

Off by default. Enables GET /v1/problems?query= when ELASTIC_ENABLED=true. Requires a reachable cluster at ELASTIC_ENDPOINT — startup fails if ES is enabled but unreachable.

Not included in Coolify compose. To enable on a custom stack, uncomment the elasticsearch service in compose, set ELASTIC_ENABLED=true, and see Configuration.

Scale judges

docker compose -f compose/docker-compose.backend.yml up -d --scale nextjudge-judge=3

Throughput scales roughly with workers × (1 / avg_submission_seconds). Monitor queue depth rather than web container CPU.

Database ops

GORM AutoMigrate on data layer boot. pg_dump before upgrades.
Review src/data-layer/src/schema_updates.sql for manual migration notes
No SEED_DATA in prod
Test restore from backup on a schedule

Health

curl -sf https://api.yourdomain.com/healthy && echo ok

Also available: GET /health, GET /. Judges have no HTTP health endpoint — monitor queue depth, PENDING age and container restarts.

Security

Patch judge images regularly
Rate-limit /v1/basic_login, /v1/basic_register, and password-reset routes at the proxy
Set TRUSTED_PROXY=true on the data layer when it runs behind a reverse proxy
Keep PASSWORD_RESET_DEBUG=false and ALLOW_INSECURE_PASSWORD_RESET=false in production
Network-separate judge workers from internal admin tools
Password reset requires a one-time token (see Authentication — Password reset)

Upgrade playbook

pg_dump
Read src/data-layer/src/schema_updates.sql and release notes for your version
Pull or build images (docker buildx bake or prebuilt pull)
Restart data layer (migrations) → judges → web
Submit a known-AC solution. If that fails, roll back images before investigating new issues.

Troubleshooting

Symptom	Likely cause
API reachable from host, not from browser	`NEXT_PUBLIC_API_URL` points at an internal hostname
CORS errors in browser console	`CORS_ORIGIN` missing the web app’s public origin
Submissions stay `PENDING`	Judge workers down, RabbitMQ auth mismatch, or wrong `JUDGE_PASSWORD`
Login succeeds then loops	`NEXTAUTH_URL` does not match the HTTPS URL users visit
Judge PATCH returns 401	`JUDGE_PASSWORD` differs between data layer and judge containers
Data layer won’t start with ES enabled	Elasticsearch unreachable at `ELASTIC_ENDPOINT`

Local stack: Getting started troubleshooting.