postgres-websockets VS nix

At work, we've finally replaced a large part of a custom (mostly-)web backend with PostgREST recently, and that's quite a relief: considerably less code to maintain in that project now, and that was a rather awkward code. Something akin to PostgREST's "Embedding with Top-level Filtering" [1] had to be provided for all the tables, with OpenAPI schema and a typed API (Haskell + Servant); I avoided manually writing it all down, but at the cost of poking framework internals, and maintainability suffered. It was particularly annoying that the code doesn't really do anything useful, except for standing between a database and an HTTP client, and simply mimics the database anyway. Whenever a change had to be introduced, it was introduced into the database, the backend, and the frontend simultaneously, so it wasn't even useful for some kind of compatibility.

Now PostgREST handles all that, and only a few less trivial endpoints are handled by a custom backend (including streaming, which I'm considering replacing with postgrest-websocket [2] at some point).

During the switch to PostgREST, the encountered minor issues were those with inherited tables (had to set a bunch of computed/virtual columns [3] in order to "embed" those), and with a bug on filtering using such relations (turned out it was an already-fixed regression [4], so an update helped). Also a couple of helper stored procedures (to use via /rpc/) for updates in multiple tables at once (many-to-many relationships, to edit entities along with their relationships, using fewer requests) were added (though the old custom backend didn't have that), the security policies were set from the beginning, the frontend was rewritten (which allowed to finally switch without adding more work), so it was only left to cleanup the backend.

Not using views, since as mentioned above, database changes usually correspond to frontend changes, and the API doesn't have to be that stable yet.

Happy with it so far.

[1] https://postgrest.org/en/stable/api.html#embedding-with-top-...

[2] https://github.com/diogob/postgres-websockets

[3] https://postgrest.org/en/stable/api.html#computed-virtual-co...

[4] https://github.com/PostgREST/postgrest/issues/2530

> https://github.com/NixOS/nix/pull/9911#issuecomment-19252073...

As we covered in my last post, NixOS is a amazing Linux distribution for creating stable and declared environments. Now while this is amazing for a desktop setup, it is also perfect for a home-server or home-lab.

(Nix itself is slowly chugging along with Windows via MinGW - https://discourse.nixos.org/t/nix-on-windows/1113/108 and https://github.com/NixOS/nix/issues/1320 , for example.)

Nix is a cross-platform package manager. It uses the nix programming language. Nix and NixOs are often used in the same context, but while the first is a package manager, the latter is a linux distribution based on nix.

Today I want to talk to you about Nixos. What is it? Nixos is a declarative and reproducible OS, partly taking the words used on their own page. What does that mean?

Software developers often want to customize:

1. their home environments: for packages (some reach for brew on MacOS) and configurations (dotfiles, and some reach for stow).

2. their development shells: for build dependencies (compilers, SDKs, libraries), tools (LSP, linters, formatters, debuggers), and services (runtime, database). Some reach for devcontainers here.

3. or even their operating systems: for development, for CI, for deployment, or for personal use.

Nix provision all of the above in the same language, with Nixpkgs, NixOS, home-manager, and devShells such as https://devenv.sh/. What's more, Nix is (https://nixos.org/):

- reproducible: what works on your dev machine also works in CI in prod,

- declarative: you version control and review your configurations and infrastructure as code, at a reasonable level of abstraction,

- reliable: all changes are atomic with easy roll back.

Hopping from one distro to another with a different package manager might require some time to adapt. Using a package manager that can be installed on most distro is one way to help you get to work faster. Flatpak is one of them; other alternative are Snap, Nix or Homebrew. Flatpak is a good starter, and if you have a bunch of free time, I suggest trying Nix.

- it reduces bloat, because you can generate an environment or OS image with only the software needed to run a specific program or service

My guess is that a big efficiency gain would come from the second point, because you don't waste CPU on code that you don't use.

Does this make sense? Has anyone explored this?

[0]: https://nixos.org

1) Setting up the development environment - I currently use devcontainers for most things, but may also dig into nix -> isolated, portable, repeatable development environment 2) Exploring Echo - understand routing, requests, response, etc. 3) Incorporate Templ - integration with Echo, template composition, etc. 4) Integrating TailwindCSS - config for use with Echo/Templ, development cycle, deployment, etc. 5) Add in HTMX - endpoints, template structure, concepts, etc. 6) hyperscript for interactivity - client side interactivity