How Paprika is put together

Paprika is one image, run as several services, with PostgreSQL beside it. Each service is the same program started with a different command:

Service	Command	What it does
api	api	The generation API under /v1 (port 4179): templates, renders, jobs, batches, brand kits, keys and the admin API. Renders synchronous requests in its own threads.
worker	worker	Runs queued jobs and batches and sends webhooks. Answers only its probes (port 4180). Run as many as you need.
editor	editor	Serves the editor to browsers (port 4178) and forwards their /v1 requests to the API with its own key, so the browser holds none and stays on one address.
migrate	migrate	Brings the database’s schema up to date, then exits. The API isn’t ready until it has.
editor-key	editor-key	Gives the editor an API key, keeping the one it has while it works, then exits.
db	PostgreSQL	Every record: tenants, keys, templates and versions, jobs, usage, the audit log.

The editor and the API render with the same engine: what a designer sees in the editor is what the API produces.

What is kept where

• PostgreSQL holds the records. Every row names its tenant, and a tenant’s requests can read only its own rows (security).
• The data volume (/data, shared by api and every worker) holds the bytes: uploaded fonts, images and colour profiles, template packages, records files and finished outputs, each under its tenant’s folder.
• The keys volume (/keys) holds the editor’s API key.

Nothing is sent anywhere else: Paprika fetches no images or fonts from the internet and reports usage to no one.

How a request flows

1. A designer publishes a template from the editor; the editor forwards it to the API, which keeps it as a new version.
2. A system calls the API with its key: a synchronous render answers the file at once; a job or batch is queued.
3. A worker claims the queued work in fair shares between tenants (scheduler), renders it, stores the output and sends the webhook.
4. The output is downloaded with the key, or by a signed link that works without one until it expires.

The explanation pages say more about how rendering works and why the editor and the output agree.