Configuration

Modulo is configured through environment variables. All config lives in a .env file in the backend/ directory.

Required

Required
Variable	Description
`DATABASE_URL`	Async PostgreSQL connection string
`SECRET_KEY`	32-byte hex key for JWT (JSON Web Token) signing
`FERNET_KEY`	Fernet-compatible key for credential encryption

Database

DATABASE_URL=postgresql+asyncpg://user:password@host:5432/modulo

By default, the Docker Compose setup uses port 5434 (not 5432) to avoid conflicts with local Postgres installations.

Authentication

# Static users for local development (comma-separated, user:pass format)
MODULO_USERS=admin:admin,dev:dev

# Enable demo mode (seeds demo:demo user)
MODULO_DEMO_MODE=true

Credential encryption

# Generate your own – do not use the example key in production
FERNET_KEY=replace-with-your-generated-key

Generate one:

python -c "from cryptography.fernet import Fernet; print(Fernet.generate_key().decode())"

Connectors

# GitHub App credentials (for GitHub connector)
GITHUB_APP_ID=...
GITHUB_APP_PRIVATE_KEY=...

CORS

CORS_ORIGINS=http://localhost:5173,https://modulo.run

Logging

LOG_LEVEL=INFO
MODULO_LOG_FORMAT=json

If MODULO_LOG_FORMAT is unset, plain text logs are used. Set to json for structured logging in production.

OpenTelemetry

OTEL_SDK_DISABLED=false
OTEL_EXPORTER_OTLP_ENDPOINT=http://localhost:4318   # OTLP = OpenTelemetry Protocol

Redis

REDIS_URL=redis://localhost:6380/0

Redis is used for WebSocket event broker fan-out and run event ring buffer storage (a fixed-size circular buffer for recent event replay).

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