devkit

Scaffolds custom tools for a devenv environment

fix nix flake refresh on a proj init
BT  ·  2026-10-16
68bd7f7

README.md

devkit

Shared devenv module: my personal dev tools (bug, secrets, local-code-review), a jujutsu/bash toolchain, and the customized interactive bash environment (fish-like completion, history search, etc.).

Importing devkit keeps every project’s shell identical and lets a single edit here propagate to all of them.

Use it in a project

devenv.yaml:

inputs:
  nixpkgs:
    url: github:cachix/devenv-nixpkgs/rolling
  # devenv#2205: an imported input's devenv.yaml is NOT evaluated, so the tool
  # inputs must be declared here even though devkit wires the packages.
  bug:
    url: git+https://git.kilimanjaro.io/bug
  local-code-review:
    url: git+https://git.kilimanjaro.io/local-code-review
  secrets:
    url: git+https://git.kilimanjaro.io/secrets
  devkit:
    url: git+https://git.kilimanjaro.io/devkit
    flake: false
imports:
  - devkit

That’s the whole wiring. A project’s own devenv.nix only needs its project-specific packages/env; devkit’s enterShell is concatenated with the project’s.

Each tool is added only when its input is declared. Disable one with, e.g., devkit.bug.enable = false; in devenv.nix (used by a project that ships its own wrapper, like sovrn).

Updating

Changes are pinned per project in devenv.lock:

devenv update devkit

For live, unpinned edits while iterating on devkit, temporarily point devkit.url at a sibling clone (url: path:../devkit); edits then take effect on the next devenv shell with no update.

New project scaffold

devenv init has no template flag (devenv #1718); its --from flag only affects devenv shell/test/build. Use the Nix flake template instead:

mkdir ~/projects/newthing && cd ~/projects/newthing
nix flake init --refresh -t git+https://git.kilimanjaro.io/devkit

(Local clone: nix flake init -t path:/home/btburke/projects/devkit.)

--refresh picks up the latest template commit; without it nix reuses the cached branch ref for tarball-ttl (default 1h). proj init always passes it.

Fish shell helper

fish/functions/proj.fish defines a proj function wrapping the scaffold:

proj init            # scaffold in the current directory
proj init newthing   # mkdir, cd, then scaffold

Install by symlinking into fish’s autoload directory (or wire it into your dotfiles):

mkdir -p ~/.config/fish/functions
ln -sf ~/projects/devkit/fish/functions/proj.fish ~/.config/fish/functions/proj.fish

Gotchas