A small stateful service, packaged end to end

Problem

A private dogsitting checklist needs a web interface that is small enough to operate directly while still having a reproducible path from development to an HTTPS deployment.

Constraints

Application state remains local to the service, and the initial administrator password arrives through a host-managed file rather than source configuration. Production traffic must pass through a reverse proxy while the application itself remains bound to localhost.

Investigation

Development, administrator initialization, serving, and host integration were treated as parts of one delivery surface. The standalone flake keeps the application package, test environment, command-line entry points, and NixOS service module together instead of leaving production assembly to a separate repository.

Delivered System

The repository provides the checklist web application, a Python unit-test workflow, commands to initialize an administrator and run the server, and a reusable NixOS module. Its production profile configures nginx as the HTTPS reverse proxy and enables secure cookies, trusted proxy headers, rate limits, and strict security headers.

Demonstrated Result

The application can run locally from the flake against an explicit state directory, then be enabled on NixOS through services.dogsitting. The Pseudo Design host configuration consumes that flake as an input, supplies the administrator password by file, and publishes the service through its dedicated nginx virtual host.

Handoff

The public README keeps the operational interface compact: enter the development environment, run the unit suite, initialize an administrator, serve locally, or enable the NixOS module. Host-specific state, credentials, port, and public hostname stay outside the application package.