nix-update VS NixOS-docker

You should instead use the regular fetchGit, fetchFromGitHub etc. fetchers in fairly vanilla code, and yes, that often means dealing with checksums in some form. If you truly just want to yeet the latest revision into place no matter what it is, there are ways to automate that still, such as berberman/nvfetcher, or Mic92/nix-update.

Yes, however one downside is that, afaik, the inputs are downloaded eagerly, not lazily. Alternatively there are things like nix-update and nvfetcher.

or https://github.com/Mic92/nix-update

You can also use https://github.com/Mic92/nix-update with a nixpkgs git clone.

I run [nix-update](https://github.com/Mic92/nix-update/) to update stuff. If you want to package something new, first identify the programming language/buildsystem the project is using and than look for a similar project in nixpkgs.

Luckily, I did not have to start from scratch as Nix serves their own docker image. I mounted one of my directories and was able to drop into a Nix shell with my configuration file.

There is one: https://github.com/NixOS/docker

But it's more of a Nix docker image than a NixOS one, because half of the things that NixOS gives you don't really make much sense in a docker image (systemd in a container?).

I only know of the nix package manager. https://hub.docker.com/r/nixos/nix

Ability to run buildkite agents inside a kubernetes cluster on preemble instances without need to modify agent’s Dockerfile every time new dependency comes up - was one of major reasons to learn Nix. I’m just using nixos/docker image as a base, install buildkite-agent and some base stuff like bash via nix-env inside Dickerfile, everything else lays in flake.nix of every project my dockerized nixified buildkite agent run.