feat(desktop): add git worktree and review IPC

2026-07-18 14:52:04 +00:00 · 2026-06-25 16:40:27 -05:00 · 2026-06-25 16:40:27 -05:00 · e2b8018729
commit e2b8018729
parent 86e748df13
10 changed files with 1666 additions and 191 deletions
--- a/apps/desktop/electron/git-repo-scan.cjs
+++ b/apps/desktop/electron/git-repo-scan.cjs
@ -0,0 +1,98 @@
+'use strict'
+
+// Repo-first discovery: walk bounded roots for git repos using only Node's `fs`
+// — no native addon, so it just works for anyone who pulls main (no
+// electron-rebuild). Mirrors how GitHub Desktop scans: stop at the first `.git`
+// (don't descend into a repo), cap depth, and skip heavy non-repo trees so the
+// first scan stays fast. Results are cached by the backend after the first run.
+
+const fs = require('node:fs')
+const os = require('node:os')
+const path = require('node:path')
+
+const fsp = fs.promises
+
+// Shallow on purpose: real projects live a few levels under home
+// (`~/www/repo`, `~/code/org/repo`); deeper `.git` dirs are almost always
+// fixtures/vendored/eval checkouts (e.g. `~/www/ha-evals/tasks/*/repo`). Repos
+// you actually use but keep deeper still surface via session-derived discovery,
+// so this only prunes noise, never repos with history.
+const DEFAULT_MAX_DEPTH = 3
+const MAX_CONCURRENCY = 32
+
+// Big trees that are never themselves repos and would waste the walk. Anything
+// hidden (dotdirs like .cache/.Trash/.npm) is skipped wholesale below, so this
+// only needs the non-hidden heavyweights.
+const JUNK_DIRS = new Set(['Applications', 'Library', 'node_modules', 'site-packages', 'vendor', 'venv'])
+
+async function mapLimit(items, limit, fn) {
+  let cursor = 0
+
+  async function worker() {
+    while (cursor < items.length) {
+      const index = cursor
+      cursor += 1
+      await fn(items[index])
+    }
+  }
+
+  await Promise.all(Array.from({ length: Math.min(limit, items.length) }, worker))
+}
+
+/**
+ * Scan `roots` (default: the home dir) for git repositories. Returns deduped
+ * `{ root, label }` entries. `options.maxDepth` caps recursion (default 3).
+ */
+async function scanGitRepos(roots, options = {}) {
+  const maxDepth = Number(options.maxDepth) || DEFAULT_MAX_DEPTH
+  const searchRoots = Array.isArray(roots) && roots.length > 0 ? roots : [os.homedir()]
+  const found = new Map()
+
+  async function walk(dir, depth) {
+    if (depth > maxDepth) {
+      return
+    }
+
+    let entries
+    try {
+      entries = await fsp.readdir(dir, { withFileTypes: true })
+    } catch {
+      return // unreadable / permission denied
+    }
+
+    // A `.git` DIRECTORY marks a real repo root (a main checkout). A `.git`
+    // FILE is a linked worktree or submodule — those belong to their parent
+    // repo as lanes, not as separate projects, so we don't list them (and we
+    // keep descending in case a real repo sits deeper). This is what kills the
+    // worktree/eval-repo duplicate explosion.
+    if (entries.some(entry => entry.name === '.git' && entry.isDirectory())) {
+      const root = dir.replace(/[/\\]+$/, '')
+      found.set(root, path.basename(root) || root)
+
+      return
+    }
+
+    const subdirs = []
+    for (const entry of entries) {
+      // Real directories only (skip symlinks to avoid loops), no hidden dirs, no
+      // known heavy trees.
+      if (!entry.isDirectory() || entry.name.startsWith('.') || JUNK_DIRS.has(entry.name)) {
+        continue
+      }
+
+      subdirs.push(path.join(dir, entry.name))
+    }
+
+    await mapLimit(subdirs, MAX_CONCURRENCY, sub => walk(sub, depth + 1))
+  }
+
+  await mapLimit(
+    searchRoots.map(root => String(root || '').trim()).filter(Boolean),
+    MAX_CONCURRENCY,
+    root => walk(root, 0)
+  )
+
+  return [...found.entries()].map(([root, label]) => ({ label, root }))
+}
+
+module.exports = { scanGitRepos }
--- a/apps/desktop/electron/git-review-ops.cjs
+++ b/apps/desktop/electron/git-review-ops.cjs
@ -0,0 +1,679 @@
+'use strict'
+
+// Git ops backing the coding rail + Codex-style review pane. Built on `simple-git`
+// (a maintained wrapper around the system git binary — same git the rest of the
+// app shells to, no native build) so we read structured status()/diffSummary()
+// results instead of hand-parsing porcelain. Reads degrade to null/empty on a
+// non-repo / remote backend; mutations reject so the renderer can toast.
+
+const { execFile } = require('node:child_process')
+const fs = require('node:fs/promises')
+const path = require('node:path')
+
+const simpleGit = require('simple-git')
+
+const { resolveRequestedPathForIpc } = require('./hardening.cjs')
+
+const COMMIT_CONTEXT_DIFF_MAX_CHARS = 120_000
+const COMMIT_CONTEXT_UNTRACKED_MAX = 80
+const UNTRACKED_LINE_COUNT_CONCURRENCY = 16
+const UNTRACKED_LINE_COUNT_MAX_BYTES = 1024 * 1024
+
+// GUI-launched Electron apps on macOS inherit only a minimal PATH (no
+// /opt/homebrew/bin or /usr/local/bin), so `gh` — and the `git` gh shells out
+// to — aren't found. Augment PATH with the resolved gh dir + the common
+// package-manager bins so gh runs the same way it does in a terminal.
+function ghEnv(ghBin) {
+  const extra = [ghBin ? path.dirname(ghBin) : '', '/opt/homebrew/bin', '/usr/local/bin', '/usr/bin'].filter(
+    dir => dir && dir !== '.'
+  )
+
+  return { ...process.env, PATH: [...extra, process.env.PATH].filter(Boolean).join(path.delimiter) }
+}
+
+// Run the `gh` CLI in a repo. Resolves { ok, stdout } so callers branch on
+// availability/auth without a throw. gh missing/unauthed → ok:false.
+function runGh(args, cwd, ghBin) {
+  return new Promise(resolve => {
+    execFile(
+      ghBin || 'gh',
+      args,
+      { cwd, env: ghEnv(ghBin), windowsHide: true, timeout: 30_000, maxBuffer: 8 * 1024 * 1024 },
+      (err, stdout) => resolve({ ok: !err, stdout: String(stdout || '') })
+    )
+  })
+}
+
+function gitFor(cwd, gitBin) {
+  return simpleGit({ baseDir: cwd, binary: gitBin || 'git', maxConcurrentProcesses: 4, trimmed: false })
+}
+
+// simple-git reports renames as `old => new` (and `dir/{old => new}/f`); resolve
+// to the NEW path so the row addresses the real file for diff/stage.
+function resolveRenamePath(raw) {
+  const path = String(raw || '').trim()
+
+  if (!path.includes(' => ')) {
+    return path
+  }
+
+  const brace = path.match(/^(.*)\{(.*) => (.*)\}(.*)$/)
+
+  if (brace) {
+    const [, prefix, , to, suffix] = brace
+
+    return `${prefix}${to}${suffix}`.replace(/\/{2,}/g, '/')
+  }
+
+  return path.split(' => ').pop().trim()
+}
+
+// DiffResult.files → Map<path, {added, removed}> (binary files carry no line
+// delta).
+function countsByPath(summary) {
+  const map = new Map()
+
+  for (const file of summary.files) {
+    map.set(resolveRenamePath(file.file), {
+      added: file.binary ? 0 : file.insertions,
+      removed: file.binary ? 0 : file.deletions
+    })
+  }
+
+  return map
+}
+
+// Untracked files don't appear in diffSummary(); count insertions from disk so
+// the review tree can show +N for new files (matches an all-add diff view).
+// Insertions = line count: newline bytes, plus one for a final unterminated
+// line. Binary (NUL byte) → 0, mirroring git numstat's "-".
+async function untrackedInsertions(cwd, relPath) {
+  try {
+    const fullPath = path.join(cwd, relPath)
+    const stat = await fs.stat(fullPath)
+
+    if (!stat.isFile() || stat.size > UNTRACKED_LINE_COUNT_MAX_BYTES) {
+      return 0
+    }
+
+    const buf = await fs.readFile(fullPath)
+
+    if (buf.includes(0)) {
+      return 0
+    }
+
+    let lines = 0
+
+    for (const byte of buf) {
+      if (byte === 10) {
+        lines++
+      }
+    }
+
+    return buf.length > 0 && buf[buf.length - 1] !== 10 ? lines + 1 : lines
+  } catch {
+    return 0
+  }
+}
+
+function capText(text, maxChars, label = 'truncated') {
+  const value = String(text || '')
+
+  if (value.length <= maxChars) {
+    return value
+  }
+
+  return `${value.slice(0, maxChars)}\n# ${label}: ${value.length - maxChars} chars omitted\n`
+}
+
+async function fillUntrackedCounts(cwd, files) {
+  const pending = files.filter(file => file.status === '?' && file.added === 0 && file.removed === 0)
+
+  for (let i = 0; i < pending.length; i += UNTRACKED_LINE_COUNT_CONCURRENCY) {
+    await Promise.all(
+      pending.slice(i, i + UNTRACKED_LINE_COUNT_CONCURRENCY).map(async file => {
+        file.added = await untrackedInsertions(cwd, file.path)
+      })
+    )
+  }
+}
+
+// Resolve the base ref for "all branch changes": merge-base with the remote
+// default branch (origin/HEAD), falling back to common trunk names.
+async function branchBase(git) {
+  const candidates = []
+
+  try {
+    const head = (await git.revparse(['--abbrev-ref', 'origin/HEAD'])).trim()
+
+    if (head) {
+      candidates.push(head)
+    }
+  } catch {
+    // No origin/HEAD configured.
+  }
+
+  candidates.push('origin/main', 'origin/master', 'main', 'master')
+
+  for (const ref of candidates) {
+    try {
+      const base = (await git.raw(['merge-base', 'HEAD', ref])).trim()
+
+      if (base) {
+        return base
+      }
+    } catch {
+      // Ref doesn't exist; try the next candidate.
+    }
+  }
+
+  return null
+}
+
+// Resolve the repo's default branch NAME ("main" / "master" / …), preferring
+// the remote's HEAD, then common local trunk names. Null when none is found
+// (e.g. a fresh repo with only a feature branch). Used to offer "branch off the
+// trunk" regardless of which branch you're currently on.
+async function defaultBranchName(git) {
+  try {
+    const head = (await git.revparse(['--abbrev-ref', 'origin/HEAD'])).trim()
+
+    // "origin/main" → "main"; skip the bare "origin/HEAD" placeholder.
+    if (head && head !== 'origin/HEAD') {
+      return head.replace(/^origin\//, '')
+    }
+  } catch {
+    // No origin/HEAD configured.
+  }
+
+  // Prefer a local trunk, then a remote-only one (returns the clean name either
+  // way) so "branch off main" works even before main is checked out locally.
+  for (const ref of ['refs/heads/main', 'refs/heads/master', 'refs/remotes/origin/main', 'refs/remotes/origin/master']) {
+    try {
+      await git.raw(['rev-parse', '--verify', '--quiet', ref])
+
+      return ref.replace(/^refs\/(?:heads|remotes\/origin)\//, '')
+    } catch {
+      // Ref doesn't exist; try the next candidate.
+    }
+  }
+
+  return null
+}
+
+// A status file's single-letter classification, preferring the staged (index)
+// code over the worktree code; untracked wins (simple-git marks both '?').
+function statusLetter(file) {
+  if (file.index === '?' || file.working_dir === '?') {
+    return '?'
+  }
+
+  const code = file.index && file.index !== ' ' ? file.index : file.working_dir
+
+  return (code || 'M').toUpperCase()
+}
+
+const isStaged = file => Boolean(file.index && file.index !== ' ' && file.index !== '?')
+
+async function reviewList(repoPath, scope, baseRef, gitBin) {
+  let cwd
+
+  try {
+    cwd = resolveRequestedPathForIpc(repoPath, { purpose: 'Review list' })
+  } catch {
+    return { files: [], base: null }
+  }
+
+  const git = gitFor(cwd, gitBin)
+
+  try {
+    if (scope === 'branch' || scope === 'lastTurn') {
+      const base = scope === 'branch' ? await branchBase(git) : baseRef
+
+      if (!base) {
+        return { files: [], base: null }
+      }
+
+      const range = scope === 'branch' ? `${base}...HEAD` : base
+      const summary = await git.diffSummary([range])
+      const files = summary.files.map(file => ({
+        path: resolveRenamePath(file.file),
+        added: file.binary ? 0 : file.insertions,
+        removed: file.binary ? 0 : file.deletions,
+        status: 'M',
+        staged: false
+      }))
+
+      // "Last turn" also surfaces files created since the baseline (untracked).
+      if (scope === 'lastTurn') {
+        const status = await git.status()
+
+        for (const path of status.not_added) {
+          if (!files.some(f => f.path === path)) {
+            files.push({ path, added: 0, removed: 0, status: '?', staged: false })
+          }
+        }
+      }
+
+      files.sort((a, b) => a.path.localeCompare(b.path))
+      await fillUntrackedCounts(cwd, files)
+
+      return { files, base }
+    }
+
+    // Default: uncommitted (staged + unstaged + untracked), one row per path.
+    const [status, staged, unstaged] = await Promise.all([
+      git.status(),
+      git.diffSummary(['--cached']),
+      git.diffSummary([])
+    ])
+    const stagedCounts = countsByPath(staged)
+    const unstagedCounts = countsByPath(unstaged)
+
+    const files = status.files.map(file => {
+      const filePath = resolveRenamePath(file.path)
+      const sc = stagedCounts.get(filePath) || { added: 0, removed: 0 }
+      const uc = unstagedCounts.get(filePath) || { added: 0, removed: 0 }
+
+      return {
+        path: filePath,
+        added: sc.added + uc.added,
+        removed: sc.removed + uc.removed,
+        status: statusLetter(file),
+        staged: isStaged(file)
+      }
+    })
+
+    files.sort((a, b) => a.path.localeCompare(b.path))
+    await fillUntrackedCounts(cwd, files)
+
+    return { files, base: null }
+  } catch {
+    return { files: [], base: null }
+  }
+}
+
+async function reviewDiff(repoPath, filePath, scope, baseRef, staged, gitBin) {
+  let cwd
+
+  try {
+    cwd = resolveRequestedPathForIpc(repoPath, { purpose: 'Review diff' })
+  } catch {
+    return ''
+  }
+
+  const git = gitFor(cwd, gitBin)
+  const safe = args => git.diff(args).catch(() => '')
+
+  if (scope === 'branch') {
+    const base = await branchBase(git)
+
+    return base ? safe([`${base}...HEAD`, '--', filePath]) : ''
+  }
+
+  if (scope === 'lastTurn') {
+    return baseRef ? safe([baseRef, '--', filePath]) : ''
+  }
+
+  if (staged) {
+    return safe(['--cached', '--', filePath])
+  }
+
+  const worktree = await safe(['--', filePath])
+
+  if (worktree.trim()) {
+    return worktree
+  }
+
+  // Untracked file: no worktree diff exists, so synthesize an all-add diff via
+  // --no-index (exits non-zero by design when files differ, so go around
+  // simple-git's reject-on-nonzero with a raw execFile).
+  return new Promise(resolve => {
+    execFile(
+      gitBin || 'git',
+      ['diff', '--no-index', '--', '/dev/null', filePath],
+      { cwd, windowsHide: true, timeout: 30_000, maxBuffer: 32 * 1024 * 1024 },
+      (_err, stdout) => resolve(String(stdout || ''))
+    )
+  })
+}
+
+// Working-tree-vs-HEAD diff for ONE file — the "what changed since the last
+// commit" view used by the file preview. Unlike reviewDiff this never synthesizes
+// a full-add for a clean tracked file (so a pristine file shows no diff); it only
+// all-adds a genuinely untracked file.
+async function fileDiffVsHead(repoPath, filePath, gitBin) {
+  let cwd
+
+  try {
+    cwd = resolveRequestedPathForIpc(repoPath, { purpose: 'File diff' })
+  } catch {
+    return ''
+  }
+
+  const git = gitFor(cwd, gitBin)
+  const head = await git.diff(['HEAD', '--', filePath]).catch(() => '')
+
+  if (head.trim()) {
+    return head
+  }
+
+  // No tracked changes vs HEAD. Only synthesize an all-add diff for a file git
+  // doesn't know yet; a clean tracked file must return empty.
+  const status = await git.raw(['status', '--porcelain', '--', filePath]).catch(() => '')
+
+  if (!status.trim().startsWith('??')) {
+    return ''
+  }
+
+  return new Promise(resolve => {
+    execFile(
+      gitBin || 'git',
+      ['diff', '--no-index', '--', '/dev/null', filePath],
+      { cwd, windowsHide: true, timeout: 30_000, maxBuffer: 32 * 1024 * 1024 },
+      (_err, stdout) => resolve(String(stdout || ''))
+    )
+  })
+}
+
+async function reviewStage(repoPath, filePath, gitBin) {
+  const cwd = resolveRequestedPathForIpc(repoPath, { purpose: 'Review stage' })
+
+  await gitFor(cwd, gitBin).raw(filePath ? ['add', '--', filePath] : ['add', '-A'])
+
+  return { ok: true }
+}
+
+async function reviewUnstage(repoPath, filePath, gitBin) {
+  const cwd = resolveRequestedPathForIpc(repoPath, { purpose: 'Review unstage' })
+
+  await gitFor(cwd, gitBin).raw(filePath ? ['reset', '-q', 'HEAD', '--', filePath] : ['reset', '-q', 'HEAD'])
+
+  return { ok: true }
+}
+
+// Discard changes back to the committed state. Destructive — the renderer
+// confirms first. Restores tracked files and removes untracked ones.
+async function reviewRevert(repoPath, filePath, gitBin) {
+  const cwd = resolveRequestedPathForIpc(repoPath, { purpose: 'Review revert' })
+  const git = gitFor(cwd, gitBin)
+
+  if (filePath) {
+    await git.raw(['checkout', 'HEAD', '--', filePath]).catch(() => undefined)
+    await git.raw(['clean', '-fd', '--', filePath]).catch(() => undefined)
+  } else {
+    await git.raw(['checkout', 'HEAD', '--', '.']).catch(() => undefined)
+    await git.raw(['clean', '-fd']).catch(() => undefined)
+  }
+
+  return { ok: true }
+}
+
+// Resolve a ref to a commit sha (captures the turn baseline for "Last turn").
+async function reviewRevParse(repoPath, ref, gitBin) {
+  let cwd
+
+  try {
+    cwd = resolveRequestedPathForIpc(repoPath, { purpose: 'Review rev-parse' })
+  } catch {
+    return null
+  }
+
+  try {
+    return (await gitFor(cwd, gitBin).revparse([ref || 'HEAD'])).trim() || null
+  } catch {
+    return null
+  }
+}
+
+// Commit the working tree. Mirrors VS Code: if nothing is staged, stage
+// everything first ("commit all"), then commit. Optionally push afterward,
+// setting upstream on the first push.
+async function reviewCommit(repoPath, message, push, gitBin) {
+  const cwd = resolveRequestedPathForIpc(repoPath, { purpose: 'Review commit' })
+  const git = gitFor(cwd, gitBin)
+  const status = await git.status()
+
+  if (status.staged.length === 0) {
+    await git.raw(['add', '-A'])
+  }
+
+  await git.commit(message)
+
+  if (push) {
+    const fresh = await git.status()
+
+    if (fresh.tracking) {
+      await git.push()
+    } else if (fresh.current) {
+      await git.raw(['push', '-u', 'origin', fresh.current])
+    }
+  }
+
+  return { ok: true }
+}
+
+// Gather the context the model needs to draft a commit message: the diff of
+// what *will* be committed (staged when anything is staged, else everything
+// vs HEAD — mirroring reviewCommit's "stage all when nothing staged" rule),
+// the names of untracked files (which carry no diff), and recent commit
+// subjects for style. Diff is capped so the payload stays bounded. Reads only.
+async function reviewCommitContext(repoPath, gitBin) {
+  let cwd
+
+  try {
+    cwd = resolveRequestedPathForIpc(repoPath, { purpose: 'Review commit context' })
+  } catch {
+    return { diff: '', recent: '' }
+  }
+
+  const git = gitFor(cwd, gitBin)
+  const safe = args => git.diff(args).catch(() => '')
+
+  let status
+  try {
+    status = await git.status()
+  } catch {
+    return { diff: '', recent: '' }
+  }
+
+  // What will land: staged changes if any, otherwise all tracked changes vs HEAD.
+  let diff = capText(
+    status.staged.length > 0 ? await safe(['--cached']) : await safe(['HEAD']),
+    COMMIT_CONTEXT_DIFF_MAX_CHARS,
+    'diff truncated for commit-message generation'
+  )
+
+  // Untracked files have no diff — list them so new files aren't invisible.
+  const untracked = status.not_added || []
+  if (untracked.length > 0) {
+    const visible = untracked.slice(0, COMMIT_CONTEXT_UNTRACKED_MAX)
+    const omitted = untracked.length - visible.length
+    const note =
+      `\n# New (untracked) files:\n${visible.map(p => `#   ${p}`).join('\n')}\n` +
+      (omitted > 0 ? `#   ... ${omitted} more omitted\n` : '')
+
+    diff = diff ? `${diff}${note}` : note
+  }
+
+  const recent = await git.raw(['log', '-n', '10', '--pretty=format:%s']).catch(() => '')
+
+  return { diff: diff || '', recent: String(recent || '').trim() }
+}
+
+async function reviewPush(repoPath, gitBin) {
+  const cwd = resolveRequestedPathForIpc(repoPath, { purpose: 'Review push' })
+  const git = gitFor(cwd, gitBin)
+  const status = await git.status()
+
+  if (status.tracking) {
+    await git.push()
+  } else if (status.current) {
+    await git.raw(['push', '-u', 'origin', status.current])
+  }
+
+  return { ok: true }
+}
+
+// gh availability + auth + whether this branch already has a PR. Reads only;
+// drives the PR button's enabled/label state. `ghReady` is false when gh is
+// missing OR not authenticated — either way the PR action can't run.
+async function reviewShipInfo(repoPath, ghBin) {
+  let cwd
+
+  try {
+    cwd = resolveRequestedPathForIpc(repoPath, { purpose: 'Review ship info' })
+  } catch {
+    return { ghReady: false, pr: null }
+  }
+
+  const auth = await runGh(['auth', 'status'], cwd, ghBin)
+
+  if (!auth.ok) {
+    return { ghReady: false, pr: null }
+  }
+
+  const view = await runGh(['pr', 'view', '--json', 'url,state,number'], cwd, ghBin)
+
+  if (!view.ok) {
+    // gh exits non-zero when no PR exists for the branch — that's not an error.
+    return { ghReady: true, pr: null }
+  }
+
+  try {
+    const pr = JSON.parse(view.stdout)
+
+    return { ghReady: true, pr: pr && pr.url ? { url: pr.url, state: pr.state, number: pr.number } : null }
+  } catch {
+    return { ghReady: true, pr: null }
+  }
+}
+
+// Create a PR for the current branch (pushing first so gh has a remote ref),
+// letting gh fill title/body from the commits. Returns the new PR url.
+async function reviewCreatePr(repoPath, gitBin, ghBin) {
+  const cwd = resolveRequestedPathForIpc(repoPath, { purpose: 'Review create PR' })
+
+  await reviewPush(repoPath, gitBin).catch(() => undefined)
+
+  const created = await runGh(['pr', 'create', '--fill'], cwd, ghBin)
+
+  if (!created.ok) {
+    throw new Error('gh pr create failed (is gh installed and authenticated?)')
+  }
+
+  const url = created.stdout.trim().split('\n').filter(Boolean).pop() || ''
+
+  return { url }
+}
+
+// Compact working-tree status for the composer coding rail: branch, ahead/behind,
+// per-state change counts, +/- vs HEAD, and a capped changed-file list.
+async function repoStatus(repoPath, gitBin) {
+  let cwd
+
+  try {
+    cwd = resolveRequestedPathForIpc(repoPath, { purpose: 'Repo status' })
+  } catch {
+    return null
+  }
+
+  // Session cwds can point at a deleted worktree for a moment (or forever in a
+  // stale row). simple-git throws at construction time on a missing baseDir, so
+  // fail soft and hide the coding rail instead of spamming IPC handler errors.
+  try {
+    const stat = await fs.stat(cwd)
+    if (!stat.isDirectory()) {
+      return null
+    }
+  } catch {
+    return null
+  }
+
+  let git
+  try {
+    git = gitFor(cwd, gitBin)
+  } catch {
+    return null
+  }
+  let status
+
+  try {
+    status = await git.status()
+  } catch {
+    // Not a repo / git unavailable / remote backend.
+    return null
+  }
+
+  const detached = typeof status.detached === 'boolean' ? status.detached : !status.current
+  const files = status.files.map(file => ({
+    path: file.path,
+    staged: isStaged(file),
+    unstaged: Boolean(file.working_dir && file.working_dir !== ' ' && file.working_dir !== '?'),
+    untracked: file.index === '?' || file.working_dir === '?',
+    conflicted: file.index === 'U' || file.working_dir === 'U'
+  }))
+
+  const result = {
+    branch: detached ? null : status.current || null,
+    defaultBranch: await defaultBranchName(git),
+    detached,
+    ahead: status.ahead || 0,
+    behind: status.behind || 0,
+    staged: files.filter(f => f.staged).length,
+    unstaged: files.filter(f => f.unstaged).length,
+    untracked: status.not_added.length,
+    conflicted: status.conflicted.length,
+    changed: files.length,
+    added: 0,
+    removed: 0,
+    files: files.slice(0, 200)
+  }
+
+  // +/- vs HEAD (staged + unstaged tracked changes). No HEAD yet → leave 0.
+  try {
+    const summary = await git.diffSummary(['HEAD'])
+    result.added = summary.insertions
+    result.removed = summary.deletions
+  } catch {
+    // No commits yet.
+  }
+
+  // `git diff HEAD` ignores untracked files, so a turn that only creates new
+  // files (the common case — a fresh module, a demo dir) showed +0 in the rail
+  // while the review pane counted them. Fold untracked insertions into `added`
+  // so the rail matches reality. Bounded (size cap + concurrency) like the
+  // review tree; only the capped file slice is counted so a huge untracked tree
+  // can't stall the probe.
+  try {
+    const untracked = status.not_added.slice(0, 500)
+    for (let i = 0; i < untracked.length; i += UNTRACKED_LINE_COUNT_CONCURRENCY) {
+      const batch = await Promise.all(
+        untracked.slice(i, i + UNTRACKED_LINE_COUNT_CONCURRENCY).map(path => untrackedInsertions(cwd, path))
+      )
+      result.added += batch.reduce((sum, n) => sum + n, 0)
+    }
+  } catch {
+    // Best-effort: a probe failure just leaves untracked lines uncounted.
+  }
+
+  return result
+}
+
+module.exports = {
+  branchBase,
+  fileDiffVsHead,
+  repoStatus,
+  resolveRenamePath,
+  reviewCommit,
+  reviewCommitContext,
+  reviewCreatePr,
+  reviewDiff,
+  reviewList,
+  reviewPush,
+  reviewRevParse,
+  reviewRevert,
+  reviewShipInfo,
+  reviewStage,
+  reviewUnstage
+}
--- a/apps/desktop/electron/git-review-ops.test.cjs
+++ b/apps/desktop/electron/git-review-ops.test.cjs
@ -0,0 +1,22 @@
+'use strict'
+
+const assert = require('node:assert/strict')
+const test = require('node:test')
+
+const { resolveRenamePath } = require('./git-review-ops.cjs')
+
+test('resolveRenamePath: plain path is unchanged', () => {
+  assert.equal(resolveRenamePath('src/a.ts'), 'src/a.ts')
+})
+
+test('resolveRenamePath: simple rename resolves to the new path', () => {
+  assert.equal(resolveRenamePath('old.ts => new.ts'), 'new.ts')
+})
+
+test('resolveRenamePath: brace rename resolves to the new path', () => {
+  assert.equal(resolveRenamePath('src/{old => new}/file.ts'), 'src/new/file.ts')
+})
+
+test('resolveRenamePath: brace rename collapsing a segment', () => {
+  assert.equal(resolveRenamePath('src/{lib => }/file.ts'), 'src/file.ts')
+})
--- a/apps/desktop/electron/git-worktree-ops.cjs
+++ b/apps/desktop/electron/git-worktree-ops.cjs
@ -0,0 +1,291 @@
+'use strict'
+
+// Git-driven worktree operations for the desktop "Start work" flow: spin up a
+// fresh worktree the lightest way (`git worktree add -b`), list real worktrees,
+// and remove them. Git is the source of truth; the renderer just drives these.
+
+const path = require('node:path')
+const fs = require('node:fs')
+const { execFile } = require('node:child_process')
+
+const { resolveRequestedPathForIpc } = require('./hardening.cjs')
+
+function runGit(gitBin, args, cwd) {
+  return new Promise((resolve, reject) => {
+    execFile(
+      gitBin,
+      args,
+      { cwd, windowsHide: true, timeout: 30_000, maxBuffer: 8 * 1024 * 1024 },
+      (err, stdout, stderr) => {
+        if (err) {
+          err.stderr = String(stderr || '')
+          reject(err)
+
+          return
+        }
+
+        resolve(String(stdout || ''))
+      }
+    )
+  })
+}
+
+// Parse `git worktree list --porcelain`. The first record is the main worktree.
+function parseWorktrees(out) {
+  const trees = []
+  let cur = null
+
+  for (const line of out.split('\n')) {
+    if (line.startsWith('worktree ')) {
+      if (cur) {
+        trees.push(cur)
+      }
+
+      cur = { path: line.slice(9).trim(), branch: null, detached: false, bare: false, locked: false }
+    } else if (!cur) {
+      continue
+    } else if (line.startsWith('branch ')) {
+      cur.branch = line.slice(7).trim().replace(/^refs\/heads\//, '')
+    } else if (line === 'detached') {
+      cur.detached = true
+    } else if (line === 'bare') {
+      cur.bare = true
+    } else if (line.startsWith('locked')) {
+      cur.locked = true
+    }
+  }
+
+  if (cur) {
+    trees.push(cur)
+  }
+
+  return trees
+}
+
+async function listWorktrees(repoPath, gitBin) {
+  let resolved
+
+  try {
+    resolved = resolveRequestedPathForIpc(repoPath, { purpose: 'Worktree list' })
+  } catch {
+    return []
+  }
+
+  try {
+    const out = await runGit(gitBin, ['worktree', 'list', '--porcelain'], resolved)
+
+    return parseWorktrees(out).map((tree, index) => ({
+      path: tree.path,
+      branch: tree.branch,
+      isMain: index === 0,
+      detached: tree.detached,
+      locked: tree.locked
+    }))
+  } catch {
+    return []
+  }
+}
+
+// A git-ref-safe branch name (spaces → "-", drop forbidden chars, trim edges),
+// or "" when nothing usable remains. Mirrors the renderer's `gitRef`, so a bad
+// value can't reach `git` no matter the caller (the GUI also enforces live).
+function sanitizeBranch(name) {
+  return String(name || '')
+    .replace(/\s+/g, '-')
+    .replace(/[^\w./-]/g, '')
+    .replace(/-{2,}/g, '-')
+    .replace(/\/{2,}/g, '/')
+    .replace(/\.{2,}/g, '.')
+    .replace(/^[-./]+|[-./]+$/g, '')
+}
+
+function slugify(name) {
+  const slug = String(name || '')
+    .trim()
+    .toLowerCase()
+    .replace(/[^a-z0-9]+/g, '-')
+    .replace(/^-+|-+$/g, '')
+    .slice(0, 40)
+    .replace(/-+$/g, '')
+
+  return slug || 'work'
+}
+
+// A brand-new project folder isn't a git repo — and a freshly-init'd one has no
+// commit to branch from — so `git worktree add` would fail. Make the dir a repo
+// with a root commit on the user's behalf so worktrees "just work". No-op for a
+// repo that already has commits; never touches the user's files (the seed commit
+// is `--allow-empty`), and never inits a dir that already lives inside a repo.
+async function ensureGitRepo(gitBin, dir) {
+  let needsRoot = false
+
+  try {
+    const inside = (await runGit(gitBin, ['rev-parse', '--is-inside-work-tree'], dir)).trim()
+
+    if (inside !== 'true') {
+      await runGit(gitBin, ['init'], dir)
+      needsRoot = true
+    } else {
+      // Repo exists; a worktree still needs a HEAD to branch from.
+      try {
+        await runGit(gitBin, ['rev-parse', '--verify', 'HEAD'], dir)
+      } catch {
+        needsRoot = true
+      }
+    }
+  } catch {
+    await runGit(gitBin, ['init'], dir)
+    needsRoot = true
+  }
+
+  if (needsRoot) {
+    // Inline identity so the seed commit lands even with no global git config.
+    await runGit(
+      gitBin,
+      ['-c', 'user.email=hermes@localhost', '-c', 'user.name=Hermes', 'commit', '--allow-empty', '-m', 'Initial commit'],
+      dir
+    )
+  }
+}
+
+// Resolve the repo's MAIN worktree root, so `.worktrees/` always nests under the
+// primary checkout even when called from a linked worktree.
+async function mainRoot(gitBin, cwd) {
+  const list = await listWorktrees(cwd, gitBin)
+  const main = list.find(tree => tree.isMain)
+
+  return main ? main.path : cwd
+}
+
+function uniqueDir(base) {
+  let dir = base
+  let n = 1
+
+  while (fs.existsSync(dir)) {
+    n += 1
+    dir = `${base}-${n}`
+  }
+
+  return dir
+}
+
+async function addWorktree(repoPath, options, gitBin) {
+  const resolved = resolveRequestedPathForIpc(repoPath, { purpose: 'Worktree add' })
+  // A new project's folder may not be a git repo yet — init it (with a root
+  // commit) so the worktree has something to branch from.
+  await ensureGitRepo(gitBin, resolved)
+  const root = await mainRoot(gitBin, resolved)
+  const opts = options || {}
+
+  // "Convert an existing branch into a worktree": check the branch out into a
+  // fresh worktree dir as-is (no `-b`, no new branch). Dir is named off the
+  // branch slug so it reads like the branch it carries.
+  if (opts.existingBranch) {
+    const existing = sanitizeBranch(opts.existingBranch)
+
+    if (!existing) {
+      throw new Error('Branch name is required.')
+    }
+
+    const dir = uniqueDir(path.join(root, '.worktrees', slugify(existing)))
+    await runGit(gitBin, ['worktree', 'add', dir, existing], root)
+
+    return { path: dir, branch: existing, repoRoot: root }
+  }
+
+  const slug = slugify(opts.name || `work-${Date.now().toString(36)}`)
+  const branch = sanitizeBranch(opts.branch) || `hermes/${slug}`
+  const dir = uniqueDir(path.join(root, '.worktrees', slug))
+
+  const args = ['worktree', 'add', '-b', branch, dir]
+
+  if (opts.base) {
+    args.push(String(opts.base))
+  }
+
+  try {
+    await runGit(gitBin, args, root)
+  } catch (err) {
+    // Branch name may already exist — retry checking out the existing branch
+    // into a fresh worktree dir instead of failing the whole flow.
+    if (/already exists/i.test(err.stderr || '')) {
+      await runGit(gitBin, ['worktree', 'add', dir, branch], root)
+    } else {
+      throw err
+    }
+  }
+
+  return { path: dir, branch, repoRoot: root }
+}
+
+async function removeWorktree(repoPath, worktreePath, options, gitBin) {
+  const resolvedRepo = resolveRequestedPathForIpc(repoPath, { purpose: 'Worktree remove (repo)' })
+  const resolvedTree = resolveRequestedPathForIpc(worktreePath, { purpose: 'Worktree remove (tree)' })
+  const root = await mainRoot(gitBin, resolvedRepo)
+  const args = ['worktree', 'remove']
+
+  if (options && options.force) {
+    args.push('--force')
+  }
+
+  args.push(resolvedTree)
+  await runGit(gitBin, args, root)
+
+  return { removed: resolvedTree }
+}
+
+// List local branches for the "convert a branch into a worktree" picker, most
+// recently committed first. Each carries whether it's already checked out in a
+// worktree and, when checked out, that worktree's path. Empty on a non-repo /
+// remote backend where the probe can't run.
+async function listBranches(repoPath, gitBin) {
+  let resolved
+
+  try {
+    resolved = resolveRequestedPathForIpc(repoPath, { purpose: 'Branch list' })
+  } catch {
+    return []
+  }
+
+  try {
+    const out = await runGit(
+      gitBin,
+      ['for-each-ref', '--format=%(refname:short)', '--sort=-committerdate', 'refs/heads'],
+      resolved
+    )
+    const trees = await listWorktrees(resolved, gitBin)
+    const pathByBranch = new Map(trees.filter(tree => tree.branch).map(tree => [tree.branch, tree.path]))
+
+    return out
+      .split('\n')
+      .map(line => line.trim())
+      .filter(Boolean)
+      .map(name => ({ name, checkedOut: pathByBranch.has(name), worktreePath: pathByBranch.get(name) || null }))
+  } catch {
+    return []
+  }
+}
+
+async function switchBranch(repoPath, branch, gitBin) {
+  const resolved = resolveRequestedPathForIpc(repoPath, { purpose: 'Branch switch' })
+  const target = sanitizeBranch(branch)
+
+  if (!target) {
+    throw new Error('Branch name is required.')
+  }
+
+  await runGit(gitBin, ['switch', target], resolved)
+
+  return { branch: target }
+}
+
+module.exports = {
+  addWorktree,
+  ensureGitRepo,
+  listBranches,
+  listWorktrees,
+  parseWorktrees,
+  removeWorktree,
+  sanitizeBranch,
+  switchBranch
+}
--- a/apps/desktop/electron/git-worktree-ops.test.cjs
+++ b/apps/desktop/electron/git-worktree-ops.test.cjs
@ -0,0 +1,172 @@
+'use strict'
+
+const assert = require('node:assert/strict')
+const { execFileSync } = require('node:child_process')
+const fs = require('node:fs')
+const os = require('node:os')
+const path = require('node:path')
+const test = require('node:test')
+
+const {
+  addWorktree,
+  ensureGitRepo,
+  listBranches,
+  parseWorktrees,
+  sanitizeBranch,
+  switchBranch
+} = require('./git-worktree-ops.cjs')
+
+test('sanitizeBranch: spaces → hyphens, forbidden chars dropped, edges trimmed', () => {
+  assert.equal(sanitizeBranch('beach vibes'), 'beach-vibes')
+  assert.equal(sanitizeBranch('feat/cool thing'), 'feat/cool-thing')
+  assert.equal(sanitizeBranch('  wip~^:? '), 'wip')
+  assert.equal(sanitizeBranch('///'), '')
+})
+
+test('parseWorktrees: main checkout + linked worktree', () => {
+  const out = [
+    'worktree /repo',
+    'HEAD abc123',
+    'branch refs/heads/main',
+    '',
+    'worktree /repo/.worktrees/feat',
+    'HEAD def456',
+    'branch refs/heads/hermes/feat',
+    ''
+  ].join('\n')
+
+  const trees = parseWorktrees(out)
+
+  assert.equal(trees.length, 2)
+  assert.equal(trees[0].path, '/repo')
+  assert.equal(trees[0].branch, 'main')
+  assert.equal(trees[1].path, '/repo/.worktrees/feat')
+  assert.equal(trees[1].branch, 'hermes/feat')
+})
+
+test('parseWorktrees: detached + locked flags', () => {
+  const out = ['worktree /repo/wt', 'HEAD abc', 'detached', 'locked reason', ''].join('\n')
+  const trees = parseWorktrees(out)
+
+  assert.equal(trees.length, 1)
+  assert.equal(trees[0].detached, true)
+  assert.equal(trees[0].locked, true)
+  assert.equal(trees[0].branch, null)
+})
+
+test('parseWorktrees: empty input', () => {
+  assert.deepEqual(parseWorktrees(''), [])
+})
+
+test('ensureGitRepo: inits a plain dir with a root commit so worktrees branch', async () => {
+  const dir = fs.mkdtempSync(path.join(os.tmpdir(), 'hermes-wt-'))
+  const git = (...args) => execFileSync('git', args, { cwd: dir }).toString().trim()
+
+  try {
+    await ensureGitRepo('git', dir)
+    assert.match(git('rev-parse', '--verify', 'HEAD'), /^[0-9a-f]{7,}$/)
+
+    // The whole point: a worktree can now branch off the seeded root commit.
+    execFileSync('git', ['worktree', 'add', '-b', 'wt', path.join(dir, '.worktrees', 'wt')], { cwd: dir })
+    assert.ok(fs.existsSync(path.join(dir, '.worktrees', 'wt')))
+
+    // Idempotent: an already-committed repo gets no extra commit.
+    await ensureGitRepo('git', dir)
+    assert.equal(git('rev-list', '--count', 'HEAD'), '1')
+  } finally {
+    fs.rmSync(dir, { recursive: true, force: true })
+  }
+})
+
+test('switchBranch: switches a normal checkout branch', async () => {
+  const dir = fs.mkdtempSync(path.join(os.tmpdir(), 'hermes-switch-'))
+  const git = (...args) => execFileSync('git', args, { cwd: dir }).toString().trim()
+
+  try {
+    await ensureGitRepo('git', dir)
+    execFileSync('git', ['branch', 'feature'], { cwd: dir })
+
+    await switchBranch(dir, 'feature', 'git')
+
+    assert.equal(git('branch', '--show-current'), 'feature')
+  } finally {
+    fs.rmSync(dir, { recursive: true, force: true })
+  }
+})
+
+test('listBranches: lists locals and flags the checked-out branch', async () => {
+  const dir = fs.mkdtempSync(path.join(os.tmpdir(), 'hermes-branches-'))
+
+  try {
+    await ensureGitRepo('git', dir)
+    const current = execFileSync('git', ['branch', '--show-current'], { cwd: dir }).toString().trim()
+    execFileSync('git', ['branch', 'feature'], { cwd: dir })
+
+    const branches = await listBranches(dir, 'git')
+    const names = branches.map(b => b.name).sort()
+
+    assert.deepEqual(names, [current, 'feature'].sort())
+    // The repo's own checkout is flagged; the unused branch is convertible.
+    assert.equal(branches.find(b => b.name === current).checkedOut, true)
+    assert.equal(fs.realpathSync(branches.find(b => b.name === current).worktreePath), fs.realpathSync(dir))
+    assert.equal(branches.find(b => b.name === 'feature').checkedOut, false)
+    assert.equal(branches.find(b => b.name === 'feature').worktreePath, null)
+  } finally {
+    fs.rmSync(dir, { recursive: true, force: true })
+  }
+})
+
+test('listBranches: a branch claimed by a worktree is flagged checked out', async () => {
+  const dir = fs.mkdtempSync(path.join(os.tmpdir(), 'hermes-branches-wt-'))
+
+  try {
+    await ensureGitRepo('git', dir)
+    execFileSync('git', ['branch', 'feature'], { cwd: dir })
+    // addWorktree converts the existing "feature" branch into a worktree.
+    const result = await addWorktree(dir, { existingBranch: 'feature' }, 'git')
+
+    assert.equal(result.branch, 'feature')
+    assert.ok(fs.existsSync(result.path))
+
+    const branches = await listBranches(dir, 'git')
+
+    assert.equal(branches.find(b => b.name === 'feature').checkedOut, true)
+  } finally {
+    fs.rmSync(dir, { recursive: true, force: true })
+  }
+})
+
+test('listBranches: empty on a non-repo path', async () => {
+  const dir = fs.mkdtempSync(path.join(os.tmpdir(), 'hermes-nonrepo-'))
+
+  try {
+    assert.deepEqual(await listBranches(dir, 'git'), [])
+  } finally {
+    fs.rmSync(dir, { recursive: true, force: true })
+  }
+})
+
+test('addWorktree: existingBranch checks the branch out without a new branch', async () => {
+  const dir = fs.mkdtempSync(path.join(os.tmpdir(), 'hermes-convert-'))
+  const git = (...args) => execFileSync('git', args, { cwd: dir }).toString().trim()
+
+  try {
+    await ensureGitRepo('git', dir)
+    execFileSync('git', ['branch', 'cool/feature'], { cwd: dir })
+
+    const before = git('branch', '--list').split('\n').length
+    const result = await addWorktree(dir, { existingBranch: 'cool/feature' }, 'git')
+
+    // No new branch was created — only the existing one is checked out.
+    assert.equal(git('branch', '--list').split('\n').length, before)
+    assert.equal(result.branch, 'cool/feature')
+    // Dir is named off the branch slug, nested under the main repo's .worktrees.
+    assert.match(result.path, /[/\\]\.worktrees[/\\]cool-feature/)
+    assert.equal(
+      execFileSync('git', ['branch', '--show-current'], { cwd: result.path }).toString().trim(),
+      'cool/feature'
+    )
+  } finally {
+    fs.rmSync(dir, { recursive: true, force: true })
+  }
+})
--- a/apps/desktop/electron/git-worktrees.cjs
+++ b/apps/desktop/electron/git-worktrees.cjs
@ -1,174 +0,0 @@
-'use strict'
-
-// Resolve git-worktree relationships for a set of session cwds, reading git's
-// on-disk metadata directly (no `git` spawn per path):
-//
-//   - A normal checkout has a `.git` DIRECTORY at its root → it's the main
-//     worktree; its repo root IS that directory's parent.
-//   - A linked worktree has a `.git` FILE: `gitdir: <repo>/.git/worktrees/<name>`.
-//     That admin dir's `commondir` points back at the shared `<repo>/.git`, whose
-//     parent is the main repo root.
-//
-// Grouping by repoRoot therefore clusters a repo's main checkout with all of its
-// linked worktrees, regardless of how the worktree directories are named. The
-// branch (read from the worktree's own HEAD) gives each worktree a meaningful
-// label.
-
-const fs = require('node:fs')
-const path = require('node:path')
-const { resolveRequestedPathForIpc } = require('./hardening.cjs')
-
-// Walk up from `start` to the nearest ancestor that carries a `.git` entry
-// (file for a linked worktree, dir for the main checkout). Capped so a stray
-// path can't loop forever.
-function findGitHost(start, fsImpl) {
-  let dir = start
-
-  for (let i = 0; i < 64; i += 1) {
-    const dotgit = path.join(dir, '.git')
-
-    try {
-      if (fsImpl.existsSync(dotgit)) {
-        return dir
-      }
-    } catch {
-      return null
-    }
-
-    const parent = path.dirname(dir)
-
-    if (parent === dir) {
-      return null
-    }
-
-    dir = parent
-  }
-
-  return null
-}
-
-function readBranch(gitDir, fsImpl) {
-  try {
-    const head = fsImpl.readFileSync(path.join(gitDir, 'HEAD'), 'utf8').trim()
-    const ref = head.match(/^ref:\s*refs\/heads\/(.+)$/)
-
-    if (ref) {
-      return ref[1]
-    }
-
-    // Detached HEAD: surface a short sha so the worktree still gets a label.
-    return /^[0-9a-f]{7,40}$/i.test(head) ? head.slice(0, 8) : null
-  } catch {
-    return null
-  }
-}
-
-// Given the directory that owns the `.git` entry, resolve its worktree identity.
-function resolveFromHost(host, fsImpl) {
-  const dotgit = path.join(host, '.git')
-  let stat
-
-  try {
-    stat = fsImpl.statSync(dotgit)
-  } catch {
-    return null
-  }
-
-  if (stat.isDirectory()) {
-    return {
-      repoRoot: host,
-      worktreeRoot: host,
-      isMainWorktree: true,
-      branch: readBranch(dotgit, fsImpl)
-    }
-  }
-
-  // Linked worktree: `.git` is a file pointing at the admin dir.
-  let contents
-
-  try {
-    contents = fsImpl.readFileSync(dotgit, 'utf8').trim()
-  } catch {
-    return null
-  }
-
-  const match = contents.match(/^gitdir:\s*(.+)$/m)
-
-  if (!match) {
-    return null
-  }
-
-  const adminDir = path.resolve(host, match[1].trim())
-
-  // `commondir` resolves to the shared `<repo>/.git`; fall back to walking two
-  // levels up from `<repo>/.git/worktrees/<name>` if it's missing.
-  let commonDir
-
-  try {
-    const rel = fsImpl.readFileSync(path.join(adminDir, 'commondir'), 'utf8').trim()
-    commonDir = path.resolve(adminDir, rel)
-  } catch {
-    commonDir = path.dirname(path.dirname(adminDir))
-  }
-
-  return {
-    repoRoot: path.dirname(commonDir),
-    worktreeRoot: host,
-    isMainWorktree: false,
-    branch: readBranch(adminDir, fsImpl)
-  }
-}
-
-function resolveWorktree(startPath, fsImpl = fs) {
-  let resolved
-
-  try {
-    resolved = resolveRequestedPathForIpc(startPath, { purpose: 'Worktree lookup' })
-  } catch {
-    return null
-  }
-
-  let start = resolved
-
-  try {
-    const stat = fsImpl.statSync(resolved)
-
-    if (!stat.isDirectory()) {
-      start = path.dirname(resolved)
-    }
-  } catch {
-    return null
-  }
-
-  const host = findGitHost(start, fsImpl)
-
-  if (!host) {
-    return null
-  }
-
-  return resolveFromHost(host, fsImpl)
-}
-
-// Batch entry point for the renderer: maps each requested cwd to its worktree
-// info (or null when it isn't inside a git checkout / can't be read). Dedupes so
-// many sessions sharing a cwd cost one lookup.
-async function worktreesForIpc(cwds, options = {}) {
-  const fsImpl = options.fs || fs
-  const list = Array.isArray(cwds) ? cwds : []
-  const out = {}
-
-  for (const cwd of list) {
-    if (typeof cwd !== 'string' || !cwd.trim() || cwd in out) {
-      continue
-    }
-
-    out[cwd] = resolveWorktree(cwd, fsImpl)
-  }
-
-  return out
-}
-
-module.exports = {
-  resolveWorktree,
-  worktreesForIpc
-}
--- a/apps/desktop/electron/main.cjs
+++ b/apps/desktop/electron/main.cjs
@ -55,7 +55,23 @@ const {
  buildRelaunchScript
 } = require('./update-relaunch.cjs')
 const { gitRootForIpc } = require('./git-root.cjs')
-const { worktreesForIpc } = require('./git-worktrees.cjs')
+const { addWorktree, listBranches, listWorktrees, removeWorktree, switchBranch } = require('./git-worktree-ops.cjs')
+const {
+  fileDiffVsHead,
+  repoStatus,
+  reviewCommit,
+  reviewCommitContext,
+  reviewCreatePr,
+  reviewDiff,
+  reviewList,
+  reviewPush,
+  reviewRevParse,
+  reviewRevert,
+  reviewShipInfo,
+  reviewStage,
+  reviewUnstage
+} = require('./git-review-ops.cjs')
+const { scanGitRepos } = require('./git-repo-scan.cjs')
 const { OFFICIAL_REPO_HTTPS_URL, isOfficialSshRemote } = require('./update-remote.cjs')
 const { resolveBehindCount, shouldCountCommits } = require('./update-count.cjs')
 const { runRebuildWithRetry } = require('./update-rebuild.cjs')
@ -1503,6 +1519,30 @@ function resolveGitBinary() {
  return _gitBinaryCache
 }

+// resolveGhBinary — locate the GitHub CLI. GUI-launched apps get a minimal PATH
+// that omits Homebrew (/opt/homebrew/bin, /usr/local/bin) where `gh` usually
+// lives, so a bare spawn('gh') ENOENTs even though `gh` works in the user's
+// terminal. Check the common install locations first, then PATH. Cached.
+let _ghBinaryCache = null
+function resolveGhBinary() {
+  if (_ghBinaryCache) return _ghBinaryCache
+
+  const candidates = []
+
+  if (IS_WINDOWS) {
+    candidates.push(path.join(process.env['ProgramFiles'] || 'C:\\Program Files', 'GitHub CLI', 'gh.exe'))
+    if (process.env.LOCALAPPDATA) {
+      candidates.push(path.join(process.env.LOCALAPPDATA, 'Microsoft', 'WinGet', 'Links', 'gh.exe'))
+    }
+  } else {
+    const home = app.getPath('home')
+    candidates.push('/opt/homebrew/bin/gh', '/usr/local/bin/gh', '/usr/bin/gh', path.join(home, '.local', 'bin', 'gh'))
+  }
+
+  _ghBinaryCache = candidates.find(fileExists) || findOnPath('gh') || 'gh'
+  return _ghBinaryCache
+}
+
 function recentHermesLog() {
  return hermesLog.slice(-20).join('\n')
 }
@ -2920,7 +2960,6 @@ async function ensureRuntime(backend) {
  return backend
 }

-
 function fetchJson(url, token, options = {}) {
  return new Promise((resolve, reject) => {
    const body = options.body === undefined ? undefined : Buffer.from(JSON.stringify(options.body))
@ -6596,7 +6635,164 @@ ipcMain.handle('hermes:fs:readDir', async (_event, dirPath) => readDirForIpc(dir

 ipcMain.handle('hermes:fs:gitRoot', async (_event, startPath) => gitRootForIpc(startPath))

-ipcMain.handle('hermes:fs:worktrees', async (_event, cwds) => worktreesForIpc(cwds))
+// Reveal a path in the OS file manager (Finder / Explorer / Files).
+ipcMain.handle('hermes:fs:reveal', async (_event, targetPath) => {
+  const target = String(targetPath || '').trim()
+
+  if (!target) {
+    return false
+  }
+
+  try {
+    shell.showItemInFolder(target)
+
+    return true
+  } catch {
+    return false
+  }
+})
+
+// Rename a file/folder in place. The renderer passes the existing path + a new
+// base name; the destination is resolved in the SAME parent dir so a rename can
+// never move the item elsewhere or traverse out. Rejects on a name collision.
+ipcMain.handle('hermes:fs:rename', async (_event, targetPath, newName) => {
+  const src = String(targetPath || '').trim()
+  const name = String(newName || '').trim()
+
+  if (!src || !name || name === '.' || name === '..' || name.includes('/') || name.includes('\\')) {
+    throw new Error('Invalid rename')
+  }
+
+  const dst = path.join(path.dirname(src), name)
+
+  if (dst === src) {
+    return { path: dst }
+  }
+
+  if (fs.existsSync(dst)) {
+    throw new Error(`"${name}" already exists`)
+  }
+
+  await fs.promises.rename(src, dst)
+
+  return { path: dst }
+})
+
+// Write a small UTF-8 text file (e.g. a project's IDEA.md at creation). The path
+// is hardened (resolveRequestedPathForIpc) and the parent must already exist —
+// this never creates directory trees or escapes the allowed roots, and content
+// is size-capped so it can't be abused as a bulk-write primitive.
+ipcMain.handle('hermes:fs:writeText', async (_event, filePath, content) => {
+  const raw = String(filePath || '').trim()
+
+  if (!raw) {
+    throw new Error('Invalid path')
+  }
+
+  const text = String(content ?? '')
+
+  if (text.length > 1_000_000) {
+    throw new Error('Content too large')
+  }
+
+  const resolved = resolveRequestedPathForIpc(expandUserPath(raw), { purpose: 'Write text file' })
+
+  if (!directoryExists(path.dirname(resolved))) {
+    throw new Error('Parent directory does not exist')
+  }
+
+  await fs.promises.writeFile(resolved, text, 'utf8')
+
+  return { path: resolved }
+})
+
+// Move a file/folder to the OS trash (recoverable) — the VS Code "Delete"
+// default. `shell.trashItem` routes to Finder/Explorer/Files trash per platform.
+ipcMain.handle('hermes:fs:trash', async (_event, targetPath) => {
+  const target = String(targetPath || '').trim()
+
+  if (!target) {
+    throw new Error('Invalid delete')
+  }
+
+  await shell.trashItem(target)
+
+  return true
+})
+
+// Git-driven worktree management ("Start work" flow). Errors surface to the
+// renderer as rejected promises so it can toast a friendly message.
+ipcMain.handle('hermes:git:worktreeList', async (_event, repoPath) =>
+  listWorktrees(repoPath, resolveGitBinary())
+)
+
+ipcMain.handle('hermes:git:worktreeAdd', async (_event, repoPath, options) =>
+  addWorktree(repoPath, options || {}, resolveGitBinary())
+)
+
+ipcMain.handle('hermes:git:worktreeRemove', async (_event, repoPath, worktreePath, options) =>
+  removeWorktree(repoPath, worktreePath, options || {}, resolveGitBinary())
+)
+
+ipcMain.handle('hermes:git:branchSwitch', async (_event, repoPath, branch) =>
+  switchBranch(repoPath, branch, resolveGitBinary())
+)
+
+ipcMain.handle('hermes:git:branchList', async (_event, repoPath) =>
+  listBranches(repoPath, resolveGitBinary())
+)
+
+// Compact repo status (branch, ahead/behind, change counts + files) for the
+// composer coding rail. Returns null on a non-repo / remote backend so the rail
+// hides cleanly rather than erroring.
+ipcMain.handle('hermes:git:repoStatus', async (_event, repoPath) => repoStatus(repoPath, resolveGitBinary()))
+
+// Codex-style review pane: list changed files for a scope, fetch one file's
+// unified diff, and stage / unstage / revert. Reads return empty on failure;
+// mutations reject so the renderer can toast.
+ipcMain.handle('hermes:git:review:list', async (_event, repoPath, scope, baseRef) =>
+  reviewList(repoPath, scope, baseRef, resolveGitBinary())
+)
+ipcMain.handle('hermes:git:review:diff', async (_event, repoPath, filePath, scope, baseRef, staged) =>
+  reviewDiff(repoPath, filePath, scope, baseRef, staged, resolveGitBinary())
+)
+// Working-tree-vs-HEAD diff for one file (the preview's "show the diff" view).
+ipcMain.handle('hermes:git:fileDiff', async (_event, repoPath, filePath) =>
+  fileDiffVsHead(repoPath, filePath, resolveGitBinary())
+)
+ipcMain.handle('hermes:git:review:stage', async (_event, repoPath, filePath) =>
+  reviewStage(repoPath, filePath ?? null, resolveGitBinary())
+)
+ipcMain.handle('hermes:git:review:unstage', async (_event, repoPath, filePath) =>
+  reviewUnstage(repoPath, filePath ?? null, resolveGitBinary())
+)
+ipcMain.handle('hermes:git:review:revert', async (_event, repoPath, filePath) =>
+  reviewRevert(repoPath, filePath ?? null, resolveGitBinary())
+)
+ipcMain.handle('hermes:git:review:revParse', async (_event, repoPath, ref) =>
+  reviewRevParse(repoPath, ref, resolveGitBinary())
+)
+ipcMain.handle('hermes:git:review:commit', async (_event, repoPath, message, push) =>
+  reviewCommit(repoPath, message, Boolean(push), resolveGitBinary())
+)
+ipcMain.handle('hermes:git:review:commitContext', async (_event, repoPath) =>
+  reviewCommitContext(repoPath, resolveGitBinary())
+)
+ipcMain.handle('hermes:git:review:push', async (_event, repoPath) => reviewPush(repoPath, resolveGitBinary()))
+ipcMain.handle('hermes:git:review:shipInfo', async (_event, repoPath) => reviewShipInfo(repoPath, resolveGhBinary()))
+ipcMain.handle('hermes:git:review:createPr', async (_event, repoPath) =>
+  reviewCreatePr(repoPath, resolveGitBinary(), resolveGhBinary())
+)
+
+// Repo-first project discovery: scan bounded roots for git repos (pure fs walk,
+// no native addon). Never throws to the renderer — failures yield an empty list.
+ipcMain.handle('hermes:git:scanRepos', async (_event, roots, options) => {
+  try {
+    return await scanGitRepos(roots || [], options || {})
+  } catch {
+    return []
+  }
+})

 ipcMain.handle('hermes:terminal:start', async (event, payload = {}) => {
  if (!nodePty) {
--- a/apps/desktop/electron/preload.cjs
+++ b/apps/desktop/electron/preload.cjs
@ -82,7 +82,35 @@ contextBridge.exposeInMainWorld('hermesDesktop', {
  getRecentLogs: () => ipcRenderer.invoke('hermes:logs:recent'),
  readDir: dirPath => ipcRenderer.invoke('hermes:fs:readDir', dirPath),
  gitRoot: startPath => ipcRenderer.invoke('hermes:fs:gitRoot', startPath),
-  worktrees: cwds => ipcRenderer.invoke('hermes:fs:worktrees', cwds),
+  revealPath: targetPath => ipcRenderer.invoke('hermes:fs:reveal', targetPath),
+  renamePath: (targetPath, newName) => ipcRenderer.invoke('hermes:fs:rename', targetPath, newName),
+  writeTextFile: (filePath, content) => ipcRenderer.invoke('hermes:fs:writeText', filePath, content),
+  trashPath: targetPath => ipcRenderer.invoke('hermes:fs:trash', targetPath),
+  git: {
+    worktreeList: repoPath => ipcRenderer.invoke('hermes:git:worktreeList', repoPath),
+    worktreeAdd: (repoPath, options) => ipcRenderer.invoke('hermes:git:worktreeAdd', repoPath, options),
+    worktreeRemove: (repoPath, worktreePath, options) =>
+      ipcRenderer.invoke('hermes:git:worktreeRemove', repoPath, worktreePath, options),
+    branchSwitch: (repoPath, branch) => ipcRenderer.invoke('hermes:git:branchSwitch', repoPath, branch),
+    branchList: repoPath => ipcRenderer.invoke('hermes:git:branchList', repoPath),
+    repoStatus: repoPath => ipcRenderer.invoke('hermes:git:repoStatus', repoPath),
+    fileDiff: (repoPath, filePath) => ipcRenderer.invoke('hermes:git:fileDiff', repoPath, filePath),
+    scanRepos: (roots, options) => ipcRenderer.invoke('hermes:git:scanRepos', roots, options),
+    review: {
+      list: (repoPath, scope, baseRef) => ipcRenderer.invoke('hermes:git:review:list', repoPath, scope, baseRef),
+      diff: (repoPath, filePath, scope, baseRef, staged) =>
+        ipcRenderer.invoke('hermes:git:review:diff', repoPath, filePath, scope, baseRef, staged),
+      stage: (repoPath, filePath) => ipcRenderer.invoke('hermes:git:review:stage', repoPath, filePath),
+      unstage: (repoPath, filePath) => ipcRenderer.invoke('hermes:git:review:unstage', repoPath, filePath),
+      revert: (repoPath, filePath) => ipcRenderer.invoke('hermes:git:review:revert', repoPath, filePath),
+      revParse: (repoPath, ref) => ipcRenderer.invoke('hermes:git:review:revParse', repoPath, ref),
+      commit: (repoPath, message, push) => ipcRenderer.invoke('hermes:git:review:commit', repoPath, message, push),
+      commitContext: repoPath => ipcRenderer.invoke('hermes:git:review:commitContext', repoPath),
+      push: repoPath => ipcRenderer.invoke('hermes:git:review:push', repoPath),
+      shipInfo: repoPath => ipcRenderer.invoke('hermes:git:review:shipInfo', repoPath),
+      createPr: repoPath => ipcRenderer.invoke('hermes:git:review:createPr', repoPath)
+    }
+  },
  terminal: {
    dispose: id => ipcRenderer.invoke('hermes:terminal:dispose', id),
    resize: (id, size) => ipcRenderer.invoke('hermes:terminal:resize', id, size),
--- a/apps/desktop/scripts/bundle-electron-main.mjs
+++ b/apps/desktop/scripts/bundle-electron-main.mjs
@ -0,0 +1,33 @@
+#!/usr/bin/env node
+// bundle-electron-main.mjs — bundles electron/main.cjs into a single
+// self-contained file so the nix build doesn't need to ship node_modules/.
+//
+// `electron` is provided by the runtime; `node-pty` is staged separately
+// via stage-native-deps.cjs.  `preload.cjs` is NOT require()'d by main —
+// Electron loads it via path.join(__dirname, 'preload.cjs') — so it stays
+// as a separate file and doesn't need bundling.
+import { build } from 'esbuild'
+import { resolve, dirname } from 'node:path'
+import { fileURLToPath } from 'node:url'
+import { renameSync } from 'node:fs'
+
+const here = dirname(fileURLToPath(import.meta.url))
+const root = resolve(here, '..')
+const entry = resolve(root, 'electron/main.cjs')
+const tmp = resolve(root, 'electron/main.bundled.cjs')
+
+await build({
+  entryPoints: [entry],
+  bundle: true,
+  platform: 'node',
+  format: 'cjs',
+  target: 'node20',
+  outfile: tmp,
+  external: ['electron', 'node-pty'],
+  logLevel: 'info'
+})
+
+// Overwrite the original with the bundled version.
+renameSync(tmp, entry)
+
+console.log(`bundled ${entry}`)
--- a/apps/desktop/src/global.d.ts
+++ b/apps/desktop/src/global.d.ts
@ -93,10 +93,64 @@ declare global {
      getRecentLogs: () => Promise<{ path: string; lines: string[] }>
      readDir: (path: string) => Promise<HermesReadDirResult>
      gitRoot?: (path: string) => Promise<string | null>
-      // Resolve git-worktree identity for a batch of session cwds, reading git's
-      // on-disk metadata locally. Returns null per cwd that isn't inside a
-      // checkout (or can't be read — e.g. a remote backend's path).
-      worktrees?: (cwds: string[]) => Promise<Record<string, HermesWorktreeInfo | null>>
+      // Reveal a path in the OS file manager (Finder / Explorer).
+      revealPath?: (path: string) => Promise<boolean>
+      // Rename a file/folder in place (new base name, same parent dir).
+      renamePath?: (path: string, newName: string) => Promise<{ path: string }>
+      // Write a small UTF-8 text file (hardened path, parent must exist).
+      writeTextFile?: (path: string, content: string) => Promise<{ path: string }>
+      // Move a file/folder to the OS trash (recoverable).
+      trashPath?: (path: string) => Promise<boolean>
+      // Git-driven worktree management for the "Start work" flow.
+      git?: {
+        worktreeList: (repoPath: string) => Promise<HermesGitWorktree[]>
+        worktreeAdd: (
+          repoPath: string,
+          options?: { name?: string; branch?: string; base?: string; existingBranch?: string }
+        ) => Promise<{ path: string; branch: string; repoRoot: string }>
+        worktreeRemove: (
+          repoPath: string,
+          worktreePath: string,
+          options?: { force?: boolean }
+        ) => Promise<{ removed: string }>
+        branchSwitch: (repoPath: string, branch: string) => Promise<{ branch: string }>
+        // Local branches for the "convert a branch into a worktree" picker.
+        branchList: (repoPath: string) => Promise<HermesGitBranch[]>
+        // Compact working-tree status for the composer coding rail. Null on a
+        // non-repo / remote backend (where the Electron probe can't run).
+        repoStatus: (repoPath: string) => Promise<HermesRepoStatus | null>
+        // Working-tree-vs-HEAD unified diff for one file (the preview's diff
+        // view). Empty string when the file is unchanged or not in a repo.
+        fileDiff: (repoPath: string, filePath: string) => Promise<string>
+        // Codex-style review pane: changed files per scope, per-file diff, and
+        // stage / unstage / revert.
+        review: {
+          list: (repoPath: string, scope: HermesReviewScope, baseRef?: null | string) => Promise<HermesReviewList>
+          diff: (
+            repoPath: string,
+            filePath: string,
+            scope: HermesReviewScope,
+            baseRef?: null | string,
+            staged?: boolean
+          ) => Promise<string>
+          stage: (repoPath: string, filePath?: null | string) => Promise<{ ok: boolean }>
+          unstage: (repoPath: string, filePath?: null | string) => Promise<{ ok: boolean }>
+          revert: (repoPath: string, filePath?: null | string) => Promise<{ ok: boolean }>
+          revParse: (repoPath: string, ref?: null | string) => Promise<null | string>
+          commit: (repoPath: string, message: string, push: boolean) => Promise<{ ok: boolean }>
+          // Diff (staged-or-all) + recent commit subjects for drafting a
+          // commit message. Reads only; empty strings off-repo.
+          commitContext: (repoPath: string) => Promise<{ diff: string; recent: string }>
+          push: (repoPath: string) => Promise<{ ok: boolean }>
+          shipInfo: (repoPath: string) => Promise<HermesReviewShipInfo>
+          createPr: (repoPath: string) => Promise<{ url: string }>
+        }
+        // Repo-first discovery: scan bounded roots for git repos (depth-capped).
+        scanRepos: (
+          roots: string[],
+          options?: { maxDepth?: number }
+        ) => Promise<{ root: string; label: string }[]>
+      }
      terminal: {
        dispose: (id: string) => Promise<boolean>
        onData: (id: string, callback: (payload: string) => void) => () => void
@ -511,16 +565,92 @@ export interface HermesPreviewWatch {
  path: string
 }

-export interface HermesWorktreeInfo {
-  // Main repo root — the shared grouping key for a checkout and all its linked
-  // worktrees.
-  repoRoot: string
-  // This cwd's own worktree root.
-  worktreeRoot: string
-  // True when this is the repo's primary checkout (.git is a directory).
-  isMainWorktree: boolean
-  // Current branch (or short detached-HEAD sha), null when unreadable.
+// A real git worktree as reported by `git worktree list` (source of truth for
+// the "Start work" flow), as opposed to the session-cwd-derived grouping above.
+export interface HermesGitWorktree {
+  path: string
  branch: null | string
+  isMain: boolean
+  detached: boolean
+  locked: boolean
+}
+
+// A local branch as offered by the "convert a branch into a worktree" picker.
+// `checkedOut` marks branches git won't let a second worktree claim.
+export interface HermesGitBranch {
+  name: string
+  checkedOut: boolean
+  worktreePath: null | string
+}
+
+// A single changed path from `git status --porcelain=v2`, classified by state
+// so the coding rail / switcher can group + open the right diff.
+export interface HermesRepoStatusFile {
+  path: string
+  staged: boolean
+  unstaged: boolean
+  untracked: boolean
+  conflicted: boolean
+}
+
+// Compact working-tree status for the composer coding rail (parsed from
+// `git status --porcelain=v2 --branch`).
+export interface HermesRepoStatus {
+  branch: null | string
+  // The repo's trunk ("main" / "master" / …), so the UI can offer "branch off
+  // the default" from anywhere. Null when no trunk is detected.
+  defaultBranch: null | string
+  detached: boolean
+  ahead: number
+  behind: number
+  staged: number
+  unstaged: number
+  untracked: number
+  conflicted: number
+  // Total distinct changed paths (tracked modified + conflicts + untracked).
+  changed: number
+  // +/- line counts of tracked changes vs HEAD (staged + unstaged). Untracked
+  // files aren't in the diff, so they don't contribute lines.
+  added: number
+  removed: number
+  // Capped changed-file list (REPO_STATUS_FILE_CAP) for the diff/open actions.
+  files: HermesRepoStatusFile[]
+}
+
+// Diff scope for the review pane, mirroring Codex: uncommitted working-tree
+// changes, all changes vs the branch base, or everything since the current
+// turn began.
+export type HermesReviewScope = 'branch' | 'lastTurn' | 'uncommitted'
+
+// One changed file in the review pane (status letter, +/- lines, staged flag).
+export interface HermesReviewFile {
+  path: string
+  added: number
+  removed: number
+  // M(odified) A(dded) D(eleted) R(enamed) C(opied) U(nmerged) ?(untracked)
+  status: string
+  staged: boolean
+}
+
+export interface HermesReviewList {
+  files: HermesReviewFile[]
+  // The resolved base ref the scope diffed against (branch merge-base / turn
+  // baseline), or null for the uncommitted scope.
+  base: null | string
+}
+
+// The branch's PR (if any) as reported by `gh pr view`.
+export interface HermesReviewPr {
+  url: string
+  state: string
+  number: number
+}
+
+// gh availability/auth + the current branch's PR — drives the review pane's PR
+// button (disabled when gh isn't ready, "Open PR" vs "Create PR" otherwise).
+export interface HermesReviewShipInfo {
+  ghReady: boolean
+  pr: HermesReviewPr | null
 }

 export interface HermesReadDirEntry {