Environment variables · DelTech MUN Docs

There are three places a value can live, and which one it belongs in is decided by when it is read.

Where	What goes there	Read
GitHub Environment variable (`production`, `staging`)	`NEXT_PUBLIC_APP_URL`	At image build. Changing it needs a deploy.
`/srv/mun/app.env` on the box, mode 600	Every runtime secret	When the container starts. Edit, then `docker compose up -d app`.
`.env` locally	Your own copies	By `next dev`. Never committed.

NEXT_PUBLIC_* values are inlined into the JavaScript bundle at build time. Never put a secret behind that prefix.

Set by the image

The Dockerfile sets these; do not put them in app.env.

Variable	Why
`APP_ENV`	`production` or `staging`. Drives the staging ribbon. Replaces the old `VERCEL_ENV`.
`APP_VERSION`	The commit SHA. `/api/health` reports it, and the deploy workflow checks it.
`AUTH_URL`	Derived from `NEXT_PUBLIC_APP_URL`. Without it Auth.js puts `http://0.0.0.0:3000` into sign-in redirects.
`AUTH_TRUST_HOST`	`true`. Safe because Caddy only forwards this deployment's own hostnames.
`PORT`, `HOSTNAME`	`3000`, `0.0.0.0`.

Database

Variable	What it is
`DATABASE_URL`	Runtime connection. On a box, the Postgres container over the Compose network.
`DIRECT_URL`	Used by migrations. Locally the same as `DATABASE_URL`; against a box, a URL through an SSH tunnel.
`DATABASE_POOL_MAX`	Pool size. Code default 15; the boxes set 5, against `max_connections=50`.

Auth

Variable	What it is
`AUTH_SECRET`	Signs session tokens. Different per environment.
`ADMIN_EMAIL`	The seeded admin account.

Email

Variable	What it is
`EMAIL_TRANSPORT`	`resend` (default) or `ses`. Production stays on Resend until SES production access is granted.
`AUTH_RESEND_KEY`	Resend API key.
`SES_REGION`	Defaults to `ap-south-1`.
`AWS_ACCESS_KEY_ID`, `AWS_SECRET_ACCESS_KEY`	Read by the SES client. On the boxes, the same per-environment IAM key as S3.
`EMAIL_FROM`	Sender. Defaults to `noreply@deltechmun.in`.
`EMAIL_REDIRECT_TO`	Staging only. Sends every message to one inbox, real recipient in the subject. If it is ever unset, staging mails real people.

Storage

Variable	What it is
`S3_BUCKET`, `S3_REGION`	`deltechmun-media-prod` or `-staging`, `ap-south-1`.
`S3_ACCESS_KEY_ID`, `S3_SECRET_ACCESS_KEY`	Server only. The browser gets a presigned URL instead.
`S3_PUBLIC_BASE_URL`	Optional public origin. Defaults to the bucket's own URL.
`S3_ENDPOINT`	Optional, for MinIO or LocalStack locally.

Payments

Variable	What it is
`RAZORPAY_KEY_ID`, `RAZORPAY_KEY_SECRET`	Live keys on production, test keys on staging.
`RAZORPAY_WEBHOOK_SECRET`	Verifies webhook signatures. Unset means every webhook is rejected.
`UPI_VPA`, `UPI_PAYEE_NAME`	Fallbacks when the admin console has none.

Integrations

Variable	What it is
`CRON_SECRET`	Bearer token the cron routes require. Staging has its own value.
`GFORM_SHARED_SECRET`	Header secret for the Google Form webhook.
`SHEET_SYNC_SECRET`	Authenticates the outbound sheet mirror.
`GROQ_API_KEY`, `GROQ_MODEL`	AI import mapping. Optional.

Development and scripts only

Variable	What it is
`ALLOW_DESTRUCTIVE_SEED`	Must be `1` for the staging seed to run.
`RECRUITMENT_DB_CHECKS`	Enables the database-backed recruitment concurrency check.
`QUIZ_LOAD_*`	Options for `scripts/load-quiz.ts`.

Other files on the box

File	Holds
`/srv/mun/caddy.env`	`ACME_EMAIL` for certificate notices.
`/srv/mun/db.env`	The Postgres container's credentials.

Compose would normally expand $ inside these files, which silently empties a value such as a password hash. They are loaded with format: raw in deploy/compose.yml for that reason.

GitHub

Name	Kind	What it is
`DEPLOY_HOST`, `DEPLOY_KNOWN_HOSTS`	Environment secret	That environment's box address and host key.
`DEPLOY_SSH_KEY`	Secret	The deploy user's key.
`CRON_SECRET`	Repository secret	Production's value, used by the cron workflow.
`AWS_DEPLOY`	Repository variable	Deploys do nothing unless `true`.
`CRON_ENABLED`	Repository variable	Scheduled cron calls do nothing unless `true`.