# Interactive shell environment

Everything the shell, terminal multiplexer, git and ssh do beyond their defaults,
and where each is defined. All of it is managed declaratively through
home-manager — edit the listed file and rebuild, never the generated dotfiles.

Keyboard shortcuts have their own reference: [`KEYBINDINGS.md`](./KEYBINDINGS.md).

| Area | Defined in |
| --- | --- |
| zsh, CLI tools, tmux, ssh, auto-tmux | [`shell.nix`](./shell.nix) |
| git (+ delta, commitizen) | [`git.nix`](./git.nix) |
| vim | [`editor.nix`](./editor.nix) |
| GUI apps, GTK/Firefox theming, cursor | [`desktop.nix`](./desktop.nix) (graphical hosts only) |

Shared by every host via [`default.nix`](./default.nix); the work box also layers
[`../../system/modules/work/default.nix`](../../system/modules/work/default.nix)
on top (work email, its own ssh config, extra packages).

---

## zsh

| Feature | Notes |
| --- | --- |
| oh-my-zsh | plugins `git`, `man`, `sudo` (Esc-Esc to prepend sudo), `colored-man-pages`, `extract`; theme `robbyrussell` |
| Autosuggestion | fish-style history suggestions as you type (→ to accept) |
| Syntax highlighting | commands coloured by validity as you type |
| Completion | menu completion; the dump is rebuilt on every activation (see Maintenance) |
| History | 100k in-memory/on-disk, deduped, space-prefixed commands ignored, timestamped, **shared live across sessions** |
| History substring search | type a fragment, then ↑/↓ cycles matching past commands — works in foot, iTerm2 and the Linux TTY (both CSI and SS3 arrow encodings bound) |
| Prompt | hostname is prefixed when over SSH |

**Aliases:** `ls`/`ll`/`la`/`lt` → `eza` (icons + git), `cls` → `clear`. git aliases live in git.nix (below).

## CLI tools

| Tool | What it gives you |
| --- | --- |
| `fzf` | `Ctrl-R` fuzzy history, `Ctrl-T` file picker, `Alt-C` fuzzy cd |
| `zoxide` | `z <fragment>` jumps to frecent directories |
| `direnv` + `nix-direnv` | per-project environments auto-loaded on `cd` (cached Nix dev shells) |
| `eza` | modern `ls` (drives the ls aliases) |
| `bat` | syntax-highlighting pager; behaves like `cat` when piped |
| `nix-index` | `command-not-found`: an unknown command tells you which Nix package provides it (prebuilt DB, no manual indexing) |
| `comma` (`,`) | run an uninstalled program once: `, cowsay hi` |
| `nh` | nicer `nixos-rebuild`/`home-manager` with diffs; `$NH_FLAKE` set to the repo; weekly user-GC timer (`--keep 5 --keep-since 3d`) |

## tmux

**Auto-start:** opening any interactive terminal — foot, iTerm2, the WSL shell, the
Linux console — drops you straight into a tmux session named `main` (attach if it
exists, else create). Panes run a plain non-login zsh. It deliberately does **not**
fire for SSH sessions, VS Code's integrated terminal, already-inside-tmux, or
non-interactive shells.

| Setting | Value |
| --- | --- |
| Mode keys | vi |
| Mouse | on |
| Scrollback | 500000 lines |
| `escape-time` | 10ms (the 500ms default lagged vim's ESC) |
| `focus-events` | on (vim autoread) |
| `base-index` / `pane-base-index` | 1 |
| Splits | `prefix s` vertical, `prefix v` horizontal (stock `%`/`"` unbound) |
| Pane nav | `Alt`+arrows (no prefix) |
| Clipboard | `set-clipboard on`; foot `terminal-features` advertise truecolor/sync/OSC52/title/cursor |

**Plugins:** `sensible`, `vim-tmux-navigator` (Ctrl-h/j/k/l across vim ↔ tmux),
`yank`, `catppuccin` (Mocha statusline), `resurrect` + `continuum`
(sessions auto-save and restore across reboots).

## git

Pager is **delta**. **commitizen** is installed on every host; `cz` defaults to
Conventional Commits.

| Aliases | |
| --- | --- |
| `st` `co` `sw` `br` `ci` | status / checkout / switch / branch / commit |
| `last` `unstage` | last commit / unstage |
| `lg` | graph log, all branches |
| `cz` `cc` | `git cz <sub>` (e.g. `git cz c`) and `git cc` → commitizen prompt |

| Behaviour | |
| --- | --- |
| Pulls | rebase, with autostash + autosquash |
| Fetch | prune deleted remote branches |
| Conflicts | `zdiff3` (shows the common ancestor) |
| Diffs | histogram algorithm, colour-moved |
| `rerere` | remembers + replays conflict resolutions |
| Commit editor | full diff shown (`commit.verbose`) |
| Misc | branches sorted by date, `column.ui = auto`, `help.autocorrect = prompt`, `push.autoSetupRemote` |
| Global ignores | `result`, `result-*`, `.direnv`, `*.swp`, `.DS_Store` |
| Signing | SSH commit + tag signing (`mkDefault`, so a host without the key in its agent can disable it). Personal email `iam@emmathe.dev`; the work box overrides email + signing. |

## ssh

| Feature | Notes |
| --- | --- |
| ssh-agent | runs on Linux (launchd on macOS); keys added on **first use** so the passphrase is typed once per login session — this also feeds git commit signing |
| macOS | `UseKeychain` caches the passphrase in the login keychain |
| Gitea remote | `code.emmathe.dev` → `HostName 10.187.1.76` (DNS-override), `Port 30009`, user `git`, dedicated key, `identitiesOnly` |
| Defaults | the module's deprecated default block is opted out; equivalents kept under `settings."*"` |

The **work box keeps its own `~/.ssh/config`** (home-manager's `programs.ssh` is
forced off there) but still runs the agent.

## Maintenance behaviours

- **zcompdump reset** — `~/.zcompdump*` is removed on every activation, so a stale
  dump (pointing at `/nix/store` paths a rebuild or the weekly GC removed) can't
  break completion with `_git: function definition file not found`.
- **Weekly GC** — `nh clean` runs weekly as a user timer, keeping the last 5
  generations and anything newer than 3 days.

## Per-host differences

| | Personal Linux (sway) | macOS | Work WSL (EDaaS) |
| --- | --- | --- | --- |
| Auto-tmux | yes (foot/TTY) | yes (iTerm2) | yes (WSL shell) |
| git email | `iam@emmathe.dev` | `iam@emmathe.dev` | `…@citrix.com` (work) |
| ssh config managed | yes | yes | no (keeps corporate config) |
| ssh-agent | yes | launchd | yes (work module) |
| GUI / theming (desktop.nix) | yes | no | no |
