nix-flake-ops

name	nix-flake-ops
description	Manage Nix flake operations — update inputs, lock flake, check evaluation, and maintain flake.nix. Use when updating flake dependencies, troubleshooting lock conflicts, adding/removing inputs, or running flake checks. Integrates with the nix-flake and nix-build tools.
tags	["nix","flake","lock","inputs","maintenance"]

Nix Flake Operations Skill

Manage the ShizNix flake — inputs, lockfile, evaluation checks, and flake.nix maintenance.

When to Use

• Updating all flake inputs (nix flake update)
• Updating a single input (nix flake lock --update-input <name>)
• Adding a new flake input to flake.nix
• Removing or replacing a flake input
• Running flake evaluation checks
• Troubleshooting lockfile conflicts or hash mismatches
• After a flake.lock update that breaks evaluation

Flake Inputs Reference

The ShizNix flake has 16 inputs. Key ones:

Input	Type	Purpose	Update Cadence
nixpkgs	Primary	Main package set (nixos-unstable)	Weekly
stable	Stable pin	nixos-25.05 for pinned packages	Monthly
home-manager	User env	Home-manager module	Weekly
stylix	Theming	System-wide theming	Monthly
sops-nix	Secrets	Encrypted secrets	As needed
nixos-hardware	Hardware	Lenovo Legion modules	Monthly
nur	User repo	Nix User Repository	Monthly
nix-cachyos-kernel	Kernel	CachyOS kernel patches	Monthly

Workflow

Update All Inputs

nix flake update

Then run checks:

nix flake check
nixos-rebuild build --flake .#bhairavi

Update a Single Input

nix flake lock --update-input stylix

Add a New Input

1. Add to flake.nix inputs block:

inputs = {
  # existing inputs...
  new-input = {
    url = "github:owner/repo";
    inputs.nixpkgs.follows = "nixpkgs";
  };
};

2. Add to outputs function arguments
3. Pass to host configs as needed
4. git add flake.nix then nix flake lock

Remove an Input

1. Remove from flake.nix inputs block
2. Remove from outputs function arguments
3. Remove from host configs
4. Run nix flake lock to regenerate lockfile

Troubleshooting

Hash Mismatch / Integrity Error

nix flake lock --regenerate

Input Follows Broken

If an input's follows chain is broken, check the input's own flake.nix for the expected input name.

Evaluation Error After Update

1. Check which input caused the break: nix flake metadata
2. Pin the problematic input to a known-good revision:

nix flake lock --update-input <name> --override-input <name> github:owner/repo/<known-good-rev>

3. Or revert flake.lock with git

Verification

After any flake operation:

1. nix flake check — validate flake evaluation
2. nixos-rebuild build --flake .#bhairavi — test build
3. alejandra flake.nix — format