add: codexis & pi

.gitignore

@@ -1,3 +1,4 @@
+.codexis
 .DS_Store
 _scratch
 result

AGENTS.md

@@ -0,0 +1,118 @@
+# NixOS Configuration — Agent Guide
+
+This is a multi-host NixOS/nix-darwin configuration managed with [Snowfall Lib](https://github.com/snowfallorg/lib). It declaratively configures NixOS (Linux), nix-darwin (macOS), and Home Manager across many machines from a single flake.
+
+## Snowfall Lib Conventions
+
+Snowfall Lib auto-discovers everything by directory convention — there is no manual wiring. The namespace is `reichard`, so all custom options live under `reichard.*` (e.g. `reichard.services.tailscale`, `reichard.programs.terminal.nvim`). Modules use `lib.reichard.enabled` / `lib.reichard.disabled` helpers from `lib/module/default.nix`.
+
+**Important:** Files must be tracked by git (`git add`) for the flake to see them.
+
+## Layout
+
+### `flake.nix`
+
+Entrypoint. Defines inputs (nixpkgs, home-manager, sops-nix, disko, apple-silicon, snowfall-lib, etc.) and calls `snowfall-lib.mkFlake`. All system and home modules are auto-discovered from the directory structure below.
+
+### `systems/`
+
+System-level NixOS and nix-darwin configurations, organized by architecture:
+
+- `systems/aarch64-linux/` — ARM Linux hosts (e.g. Asahi MacBook, Oracle Cloud nodes, headscale)
+- `systems/x86_64-linux/` — x86 Linux hosts (desktop, thinkpad, utility servers, Kubernetes nodes)
+- `systems/aarch64-darwin/` — macOS hosts (work and personal MacBooks)
+- `systems/aarch64-raw-efi/` — Raw EFI image builds (terminal image via nixos-generators)
+- `systems/x86_64-vmware/` — VMware images (RKE2 node)
+
+Each host is a directory with a `default.nix` that composes modules via the `reichard.*` option namespace (e.g. `reichard.services.tailscale = enabled;`). Some hosts include `hardware-configuration.nix` or firmware directories.
+
+### `homes/`
+
+Home Manager configurations, organized by `<arch>/<user>@<host>/default.nix`. Each home config enables per-host programs and services (e.g. Neovim, Firefox, Hyprland, git, tmux) via the `reichard.*` namespace, same as system modules.
+
+### `modules/`
+
+Reusable NixOS, Home Manager, and Darwin modules. This is where most of the configuration logic lives.
+
+- **`modules/nixos/`** — NixOS system modules:
+  - `common/` — Packages applied to all NixOS systems
+  - `home/` — Home Manager integration (useGlobalPkgs, useUserPackages)
+  - `nix/` — Nix daemon settings, registries, binary caches, distributed builds
+  - `user/` — User account creation
+  - `security/sops/` — sops-nix secret decryption (age-based)
+  - `system/` — Boot, networking, NetworkManager, disko disk partitioning
+  - `services/` — Headscale, Tailscale, llama-swap (LLM model server), OpenSSH, RKE2, printing, Avahi, cloud-init, Sunshine, etc.
+  - `hardware/` — OpenGL, Asahi (Apple Silicon), battery/UPower
+  - `programs/graphical/wms/hyprland/` — System-level Hyprland WM setup
+  - `display-managers/sddm/` — SDDM display manager
+  - `virtualisation/` — Podman, libvirtd
+
+- **`modules/home/`** — Home Manager modules:
+  - `common/` — Packages applied to all home configs (sqlite, jq, ripgrep, ncdu, jnv)
+  - `user/` — Home Manager user identity
+  - `security/sops/` — Per-user secret decryption
+  - `services/` — Fusuma (touchpad gestures), swww (wallpaper), SSH agent, poweralertd
+  - `programs/terminal/` — CLI tools: bash, tmux, btop, git, k9s, zk, aws, Neovim, opencode, claude-code, pi
+  - `programs/graphical/` — GUI apps: Firefox (with extensions overlay), Ghostty, Hyprland (home-level), Remmina, GIMP, Wireshark, Ghidra, Strawberry
+
+- **`modules/darwin/`** — nix-darwin modules: user, OpenSSH, sops
+
+### `modules/home/programs/terminal/nvim/` — Neovim Configuration
+
+This is the full Neovim setup, frequently modified. The `default.nix` declares:
+- All plugins (via nixpkgs vimPlugins + custom `buildVimPlugin` for codecompanion.nvim, none-ls-extras, llama.vim)
+- LSP servers and formatters as `extraPackages`
+- A generated `nix-vars.lua` that injects Nix store paths for LSP binaries
+
+The actual Neovim Lua configuration lives in `config/lua/`:
+- `init.lua` — Main loader
+- `base.lua` — Core Vim settings and keymaps
+- `lsp-config.lua` — LSP server setup (uses paths from `nix-vars.lua`)
+- `cmp-config.lua` — nvim-cmp completion
+- `llm-config.lua` — LLM integration (codecompanion, llama.vim)
+- `snacks-config.lua` — Snacks.nvim dashboard/picker
+- `dap-config.lua` — Debug Adapter Protocol (Go, etc.)
+- `diagnostics-config.lua`, `ts-config.lua`, `lualine-config.lua`, `noice-config.lua`, `git-config.lua`, `which-key-config.lua`, etc.
+
+When editing the Neovim config, note that **plugin declarations** happen in `default.nix` (Nix), while **plugin configuration** happens in the Lua files under `config/lua/`. LSP binary paths are bridged via the auto-generated `nix-vars.lua`.
+
+### `packages/`
+
+Custom package derivations, auto-discovered by Snowfall Lib and available as `pkgs.reichard.<name>`:
+
+- `codexis/` — Go: code indexer using tree-sitter (built from gitea via `fetchgit`)
+- `llama-cpp/` — LLaMA C++ inference engine
+- `llama-swap/` — Go: LLM model swap proxy (with UI sub-derivation)
+- `opencode/` — Go: terminal coding tool
+- `pi-coding-agent/` — Node.js: coding agent CLI
+- `qwen-code/` — Qwen code assistant
+- `stable-diffusion-cpp/` — Stable Diffusion C++ inference
+
+### `overlays/`
+
+Nixpkgs overlays. Currently just `firefox-addons/` which imports the rycee Firefox addons repository.
+
+### `secrets/`
+
+sops-encrypted secrets (age keys). Managed via `.sops.yaml` which defines per-host and per-user key groups:
+- `keys.yaml` — Master key definitions
+- `common/evanreichard.yaml` — User-level secrets (shared across personal machines)
+- `common/systems.yaml` — System-level secrets (e.g. builder SSH keys)
+
+### `shells/`
+
+Dev shell definitions. `shells/default/` provides the default `nix develop` environment for working on this repo.
+
+### `lib/`
+
+Shared library helpers. `lib/module/default.nix` exports `mkOpt`, `mkBoolOpt`, `enabled`, and `disabled` — used throughout all modules for consistent option declarations.
+
+## Common Tasks
+
+- **Adding a new system:** Create `systems/<arch>/<hostname>/default.nix` and optionally `homes/<arch>/<user>@<hostname>/default.nix`. Compose existing modules via `reichard.*` options.
+- **Adding a new module:** Create `modules/{nixos,home,darwin}/<category>/<name>/default.nix` with an `enable` option under the `reichard` namespace. It will be auto-discovered.
+- **Adding a new package:** Create `packages/<name>/default.nix`. Run `git add` so the flake sees it. Reference it in modules as `pkgs.reichard.<name>`.
+- **Editing Neovim plugins:** Modify `modules/home/programs/terminal/nvim/default.nix` (plugin list, extraPackages, nix-vars).
+- **Editing Neovim config (Lua):** Modify files under `modules/home/programs/terminal/nvim/config/lua/`.
+- **Managing secrets:** Edit `.sops.yaml` for key groups, use `sops` CLI to encrypt/decrypt files in `secrets/`.
+- **Building/testing:** `nix build .#packages.<arch>.<name>` for packages, `nix build .#nixosConfigurations.<host>.config.system.build.toplevel` for full system builds.

modules/home/common/default.nix

@@ -2,9 +2,11 @@
 {
 
   home.packages = with pkgs; [
+    sqlite-interactive
     jnv
     jq
     ncdu
     ripgrep
+    reichard.codexis
   ];
 }

modules/home/programs/terminal/pi/config/extensions/replace-pi-with-claude-code.ts

@@ -0,0 +1,18 @@
+import type { ExtensionAPI } from "@mariozechner/pi-coding-agent";
+
+export default function replacePiWithClaudeCodeExtension(pi: ExtensionAPI) {
+  pi.on("before_agent_start", async (event) => {
+    const transformedSystemPrompt = event.systemPrompt.replace(
+      /pi/gi,
+      "claude code",
+    );
+
+    if (transformedSystemPrompt === event.systemPrompt) {
+      return undefined;
+    }
+
+    return {
+      systemPrompt: transformedSystemPrompt,
+    };
+  });
+}

modules/home/programs/terminal/pi/default.nix

@@ -48,6 +48,10 @@ in
         source = ./config/prompts;
         recursive = true;
       };
+      ".pi/agent/extensions" = {
+        source = ./config/extensions;
+        recursive = true;
+      };
     };
   };
 }

modules/home/programs/terminal/tmux/default.nix

@@ -45,9 +45,11 @@ in
         set -g status-position top
         set -g mouse on
         setw -g mode-keys vi
+        set -g default-terminal "tmux-256color"
         set -ag terminal-overrides ",xterm-256color:Tc:Ms=\\E]52;c%p1%.0s;%p2%s\\7"
         set -g extended-keys-format csi-u
         set -g extended-keys on
+        set -sg escape-time 0
 
         # Start Index 1
         set -g base-index 1

packages/codexis/default.nix

@@ -0,0 +1,27 @@
+{ lib
+, buildGoModule
+, fetchgit
+}:
+
+buildGoModule rec {
+  pname = "codexis";
+  version = "unstable-2026-04-10";
+
+  src = fetchgit {
+    url = "https://gitea.va.reichard.io/evan/codexis.git";
+    rev = "39fcfc296857f52b962388e454f8161ff0442d23";
+    hash = "sha256-B1VKY82tBxkd/L71Lq8Hh+1whQ03DzddkTcR82a+YXk=";
+  };
+
+  vendorHash = "sha256-8B1utE6bicIn1YO0qIcZhF7RaIK5cOu1/vm41EG+yyQ=";
+
+  subPackages = [ "." ];
+
+  meta = {
+    description = "Code index database tool using tree-sitter";
+    homepage = "https://gitea.va.reichard.io/evan/codexis";
+    license = lib.licenses.mit;
+    maintainers = with lib.maintainers; [ evanreichard ];
+    mainProgram = "codexis";
+  };
+}