Streamdown's per-Block parse cost grows with the live tail's length and
is unavoidable inside the block-memo pattern (industry standard, see
findings doc). The fix is to stop having that work block the main thread.
`<DeferStreamingText>` is a 12-line wrapper that reads message-part state
via `useMessagePartText`, runs it through `useDeferredValue`, and
re-publishes via assistant-ui's `<TextMessagePartProvider>`. The inner
`<StreamdownTextPrimitive>` reads the deferred value through the normal
`useMessagePartText` hook — no fork, no internal-path imports, fully on
assistant-ui's public API. React's concurrent scheduler then:
- abandons in-flight deferred renders when a newer token arrives, so
intermediate states get skipped under fast streams
- deprioritises the markdown render when the main thread has urgent
work (typing, scroll), so input stays responsive even while a
100ms parse is queued
Streamdown already uses `useTransition` for its block-array setState;
this lifts the deferral up to the consumer boundary so it covers the
whole pipeline (preprocess → split → repair → parse → render).
A/B on the 34 MB session, 300 tokens at 50 tok/sec, markdown chunks
(four trials each, with the 33ms flush throttle on for both):
| | avgFps | p99 frame | LTs/5s | max LT | typing-while-stream p95 |
|---|---|---|---|---|---|
| pre | 54.3 | 41 ms | 1.7 | 110 ms | ~17 ms |
| post | 58.5 | 31 ms | 2.0 | 117 ms | 14-18 ms |
Longtask count + max LT unchanged — useDeferredValue doesn't reduce
CPU, only its priority. The avgFps lift and p99 frame drop are the
proof that the existing CPU is no longer blocking 60 fps cadence. One
clean run logged MUTATIONS=0 — React skipped every intermediate text
state and only committed the final one (textbook deferred-value
behaviour).
The actually-reduce-CPU path is replacing the parser with a state
machine like Flowdown — left for a future PR; see
`apps/desktop/scripts/profile-typing-lag.md` for the full investigation.
`scheduleDeltaFlush` previously coalesced via `requestAnimationFrame`
only. The "at most one flush per frame" guarantee that gives you is fine
for fast streams (>~80 tok/sec) where multiple tokens arrive within a
single frame, but breaks down at typical LLM token rates (30-80 tok/sec)
where each token arrives slower than the rAF cadence and triggers its
own React commit + Streamdown markdown re-parse.
Track `lastFlushAt` and require at least 33 ms between two flushes.
React 18+ auto-batching probabilistically already collapsed some of
these, but the floor makes it deterministic.
A/B on the 34 MB session, 300 tokens at 50 tok/sec (markdown chunks):
| | avgFps | p99 frame | LTs / 5 s | max LT |
|---|---|---|---|---|
| no floor (current rAF) | 54.0 | 38 ms | 2.0 | 145 ms |
| 33 ms floor (this PR) | 54.3 | 41 ms | 1.7 | 110 ms |
`inter-mutation` p50 also tightens from 22-28 ms to a clean 33 ms,
which is the expected signature of a deterministic floor. Doesn't fully
solve the user's perceived hitches — Streamdown's per-Block parse cost
when the last block grows past ~2 k chars is still the elephant — but
it consistently shaves the worst-case longtask and makes the streaming
cadence visibly steadier.
Also threads a matching `flushMinMs` option through the synthetic
stream driver in `perf-probe.tsx` + `scripts/measure-synthetic-stream.mjs`
so the harness can A/B both regimes without spending LLM credits.
See `scripts/profile-typing-lag.md` for the full investigation.
Drops the React `<Profiler>` approach (no-op because Vite is currently
serving the production React build) in favor of an externally-observable
measurement stack: rAF frame intervals, `PerformanceObserver({entryTypes:
['longtask']})`, and a `MutationObserver` on the live streaming message.
Adds a synthetic stream driver — `window.__PERF_DRIVE__.stream({...})` —
that pushes tokens through the live `$messages` atom at a controlled rate,
so the assistant-ui runtime, incremental repository, and Streamdown
markdown pipeline see the same workload they'd see during a real LLM
stream, without the LLM cost.
The driver lives in `src/app/chat/perf-probe.tsx`; `main.tsx` side-imports
it under `import.meta.env.MODE !== 'production'` so it tree-shakes out of
prod builds. (Using `MODE` rather than `DEV` because our Vite setup
currently reports `DEV=false` even under `vite dev` — see the dev-build
note in `profile-typing-lag.md`.)
Scripts:
- measure-synthetic-stream.mjs drive synthetic + record frame/longtask/mutation
- profile-synth-stream.mjs CPU profile + top self-time during synthetic
- measure-real-stream.mjs same harness, real LLM stream
- profile-real-stream.mjs CPU profile bracketing the real stream window
- eval.mjs / reload.mjs small CDP helpers
A real-LLM measurement on Cloud Shadows (gpt-4o-mini, 39 s window) showed
12 longtasks in the same 75-127 ms range the synthetic predicted, so the
synthetic is a faithful proxy.
Follow-up to the Enter-jump fix. The first version did a synchronous
re-pin loop inside the on-scroll handler when the browser clamped our
`scrollTop = scrollHeight` write short of the new bottom; that gave a
tight 4 px visible jump on Enter, but during streaming the
ResizeObserver fires many times per second as content grows, and each
RO callback re-entered the pin loop. CPU profile showed
`Virtualizer.getMaxScrollOffset` climbing to 22 ms self over a typing-
during-streaming window — the sync re-pin path was paying tanstack-
virtual's recompute cost ~3× per token.
Re-architect:
- RO callback coalesces to one pin per animation frame. Streaming-rate
RO bursts now cost the same as a single per-frame pin.
- The on-scroll programmatic-counter guard remains (it's what prevents
the false-disarm bug when the browser clamps a write). It no longer
does sync re-pins; the next RO/rAF will catch up.
- The useLayoutEffect on groupCount (the path that fires on user
submit / new turn arrival) ALSO schedules one rAF pin in addition to
the synchronous pin. This catches the case where React mounts the
new message in a second commit (after our layout effect ran), which
grows scrollHeight again. Two pins instead of a tight loop, paid only
once per turn change.
Net effect on the Cloud Shadows long thread:
enter-jump transient: 12–20 px for 1 frame (was 49 px permanent)
CPU during stream+type: `getMaxScrollOffset` dropped out of top-5
self-time list
typing-during-stream: p50 ~10 ms paint, p99 ~20 ms (1 frame),
occasional 40 ms+ outliers during burst
token arrivals
Also adds scripts/profile-long-stream.mjs: 20-second streaming profile
with per-500ms FPS histogram + content-length tracking, so we can see
whether streaming render cost grows with message length (it doesn't —
sustained 60 fps).
User reported: after pressing Enter on a long thread, the view jumps up
— the just-submitted message disappears below the fold. Confirmed via
apps/desktop/scripts/measure-jump.mjs:
before: distFromBottom 0 → 49.5px, sticks there permanently
after: distFromBottom 0 → ~0 (worst case 4px for one frame)
Root cause in useThreadScrollAnchor (thread-virtualizer.tsx):
1. The sticky-bottom logic disarmed on any scroll event where
`scrollTop < lastTopRef.current`. That check can't distinguish a
user scrolling up from a programmatic `pinToBottom` write that
the browser clamped short of bottom (because content also grew in
the same frame, so `scrollTop = scrollHeight` lands at
`scrollHeight - clientHeight` for the OLD scrollHeight, which is
now below the NEW scrollHeight). Result: sticky-bottom disarmed
permanently on the user's first submit.
2. There was no synchronous pin tied to React's commit phase. By the
time the ResizeObserver fired and re-pinned, the user had already
seen ~50ms of "message below the fold" — visually that reads as the
view jumping up.
Fix:
- `programmaticScrollPendingRef` counter tracks scroll events we
expect to be ours (one per `pinToBottom` write). The scroll handler
skips the disarm check when consuming a pending tick, keeps the
arm bit true, and re-pins synchronously if the browser clamped us
short of bottom. A depth cap (8) breaks runaway loops in
pathological streaming-burst layouts.
- `useLayoutEffect` on `groupCount` increase pins BEFORE the browser
paints, eliminating the visible ~50ms window between optimistic
user-message insert and the RO/scroll-event chain firing.
Verified on the long Cloud Shadows thread (7-8 turns, ~11k px tall):
all three repro runs now hold within 0–4 px of bottom across the
post-Enter transition. Submit latency unchanged (paint 77–107 ms),
streaming-typing latency unchanged.
Also adds three debug harnesses:
- measure-jump.mjs — sample thread scroll across Enter
- probe-thread.mjs — dump current thread / scroll state
- diag-jump.mjs — intercept scrollTop + RO + mutations across Enter
Re-ran the leak harness on a populated session (Phaser thread) for both
unpatched and patched builds. The original 'listener leak' was transient
warm-up cost, not a steady-state leak — both versions show 0 listener
growth/round in steady state.
The load-bearing number is forced layouts per character:
unpatched (HEAD~2): 7.02 layouts/char
patched (HEAD): 2.35 layouts/char (3× fewer)
The patches reduce per-char forced-layout work to Blink's natural floor.
Document node count and heap are flat in both builds.
The slowest user-felt path is typing into the composer while the
assistant is streaming. Profile (scripts/profile-under-stream.mjs):
FadeText measureOverflow self time: 35.8 ms → 18.1 ms (-50%)
total active CPU during 7s window: ~150 ms → ~50 ms
Two changes in src/components/ui/fade-text.tsx:
1. Drop the `useEffect([children])` that re-ran `measureOverflow`
(reads scrollWidth + clientWidth — forced layout) on every parent
re-render. `useResizeObserver` already fires the same callback on
mount and whenever the host span's box size changes; that covers
the only case where overflow state can legitimately change. The
previous explicit useEffect was a forced-layout flush on every
parent render, which during streaming meant every token tick.
2. Wrap the component in `memo` with a custom comparator that
short-circuits the entire render when scalar string `children` and
the className/fadeWidth/style props are unchanged. The hot path
was tool-fallback's title chips being re-rendered by parent
streaming updates even though their text was stable; memo+
comparator skips that.
Also adds two harness scripts under apps/desktop/scripts/:
- latency-under-stream.mjs (key→paint latency while a turn streams)
- profile-under-stream.mjs (CPU profile while a turn streams)
Updates profile-typing-lag.md with the streaming numbers and confirms
the Enter→paint submit path is already fast (≤320ms on the populated
session; the 2s "stall after Enter" the user noticed once was a
one-time cold-start, not reproducible at the UI layer).
I'd guess the felt jank in real use is fast-burst typing during a
long-form streaming reply (code blocks + markdown lists multiply the
per-token render cost). The CPU savings here scale linearly with
token volume.
Empirical work via CDP harnesses under apps/desktop/scripts/ (see
profile-typing-lag.md):
jsListeners growth (per round of 200 chars + GC):
before: +35 (verified leak — listeners stuck after 1st trigger popover use)
after: +0
Four narrow edits in src/app/chat/composer/index.tsx:
1. Drop the per-keystroke `editorRef.current.scrollHeight` read used to
decide composer expansion. Replace with `draft.length > 60` heuristic;
the existing ResizeObserver still catches edge cases. `scrollHeight`
is a forced-layout call and was firing on every char until the first
wrap.
2. Bucket measured composer height to 8px before writing
`--composer-measured-height` / `--composer-surface-measured-height`
on `documentElement`. Without this, the editor grows ~1px per char,
setProperty fires every keystroke, computed style is invalidated tree-
wide.
3. Remove the dead `$composerDraft` two-way sync. Nothing outside the
composer subscribed to that atom (verified via grep). Two useEffects
on `[draft]` were pushing draft→atom and atom→aui per keystroke for
no consumer. Also drop the per-keystroke
`reconcileComposerTerminalSelections` call; it was pruning stale
labels for `terminalContextBlocksFromDraft`, but that helper already
ignores labels not in the current submitted text, so pruning per
keystroke was just bookkeeping.
4. `refreshTrigger` fast-bails when the draft contains neither `@` nor
`/`. Previously `textBeforeCaret(editor)` ran on every input/keyup
regardless; `range.toString()` inside is O(n) over draft length.
Synthetic typing latency p50/p90/p99 is similar before vs after on a
freshly-loaded session (Blink can already handle ~30cps typing into a
contentEditable on its own); the real win is the listener leak being
gone and the global computed-style invalidations dropping ~8× when the
composer is sitting at a fixed height row.
The `Enter → stall` follow-up (see profile-typing-lag.md §"Submit /
TTFT stall") is unmeasured here — needs a throwaway session because
the harness fires a real prompt. Not blocking this commit.
The previous dependency, @homebridge/node-pty-prebuilt-multiarch@0.13.1,
publishes no win32-arm64 prebuilds on its v0.13.x line, and its v0.14.x
betas (which do add an arm64 Windows build) ship no electron-vXXX-win32-
arm64 prebuilds at all -- so packaged Electron 40 builds (NMV 143) would
fail at runtime even on a successful npm install. Net effect: the
desktop's integrated terminal was unbuildable on Windows-on-ARM, in
both dev (npm install fails: 404 fetching the node-vXXX-win32-arm64
prebuilt) and packaged builds (no Electron-ABI prebuilt exists).
The homebridge fork was originally created because upstream node-pty
shipped no prebuilds at all. That hasn't been true since node-pty@1.0
(April 2024), which:
- bundles prebuilts for mac (arm64+x64) and Windows (arm64+x64) directly
inside the npm tarball -- no GitHub-Releases fetch, no missing-binary
failure mode
- uses N-API (node-addon-api) for ABI stability across Node and Electron
major versions, so the same pty.node binary loads under Node 22 (dev)
and Electron 40+ (packaged) without per-ABI rebuilds
- is what VS Code, Hyper, and Theia actually ship
API surface is identical (spawn / onData / onExit / write / resize /
kill) -- no call-site changes needed.
Specifically:
- apps/desktop/package.json: replace the @homebridge fork with
node-pty@1.1.0 (exact pin). Widen `asarUnpack` from `["**/*.node"]`
to also unpack `**/prebuilds/**`, because node-pty ships runtime-
execed helpers alongside its .node files (darwin spawn-helper has no
extension and would not be matched by `**/*.node`; conpty.dll,
OpenConsole.exe, winpty.dll, winpty-agent.exe on Windows are also
exec'd at runtime and cannot live inside asar).
- apps/desktop/electron/main.cjs: update both require() strings to
match the new package name and the new staged path under
resources/native-deps/node-pty/.
- apps/desktop/scripts/stage-native-deps.cjs: point at node_modules/
node-pty. node-pty's prebuilts live under prebuilds/<plat>-<arch>/
(not build/Release/), so update the include glob to copy that dir.
Per-arch staging keeps the resource bundle small (target arch comes
from npm_config_arch when electron-builder cross-builds, else
process.arch). Explicitly enumerate file types in the prebuilds glob
so the ~25 MB of .pdb debug symbols that prebuild-install bundles
for Windows crash analysis don't bloat the installer (29 MB -> 2.6 MB
staged on win32-arm64). Re-assert +x on the darwin spawn-helper
defensively, since a stripped mode bit would manifest as a silent
ENOENT at first pty.spawn().
- apps/desktop/scripts/test-desktop.mjs: update expectedNativeDepPaths()
and its assertion site to look at prebuilds/<plat>-<arch>/ instead of
build/Release/. Add an explicit spawn-helper-exists check on darwin
so a regression in the asarUnpack glob would fail loudly in CI rather
than at first PTY spawn.
Trade-off: Linux end-users lose prebuilts and fall back to building
node-pty from source on `npm install`. Acceptable because Hermes
ships no Linux desktop builds (desktop-release.yml matrix is mac + win
only, package.json declares no `linux` target), and Linux developers
hacking on the desktop already need a C++ toolchain for the rest of
the stack.
Verified on Windows 11 ARM64 (Snapdragon):
npm install -> exit 0
node -e "require('node-pty').spawn(...)" round-trip -> OK
stage-native-deps -> 27 files, 2.6 MB
load from staged tree (simulates packaged fallback) -> ConPTY
round-trip OK
Converges the Windows packaged desktop installer onto a single canonical
install topology: drop the Electron shell only (~80MB instead of ~500MB),
clone Hermes Agent at a build-time-pinned commit on first launch via
install.ps1's stage protocol, and treat the resulting git checkout at
%LOCALAPPDATA%\hermes\hermes-agent\ as the canonical install location
(same path the CLI installer uses). Future updates flow through the
existing applyUpdates() git-pull path.
Replaces the previous fat-installer architecture where the .exe bundled
a pre-staged hermes-agent source tree under resources/hermes-agent/ that
was then sync'd into ACTIVE_HERMES_ROOT at launch -- a complicated
factory-vs-active dance with several footguns (FACTORY_HERMES_ROOT
mismatch on path resolve, isGitCheckout guard regressions, pyproject
hash drift detection inside the sync loop).
Architecture overview
---------------------
Build time
apps/desktop/scripts/write-build-stamp.cjs writes
apps/desktop/build/install-stamp.json with {commit, branch, builtAt,
dirty}. Honours $GITHUB_SHA / $GITHUB_REF_NAME in CI, falls back to
`git rev-parse HEAD` locally.
apps/desktop/scripts/stage-native-deps.cjs copies the runtime subset
of @homebridge/node-pty-prebuilt-multiarch from the workspace-root
node_modules into apps/desktop/build/native-deps/. Workspace dedup
hoists this dep to the root, out of reach of electron-builder's
`files:`-restricted collector; staging gives us a deterministic
path to extraResources.
electron-builder ships both into resources/install-stamp.json and
resources/native-deps/ respectively.
Boot resolver (electron/main.cjs)
Resolver order:
1. HERMES_DESKTOP_HERMES_ROOT override
2. SOURCE_REPO_ROOT (dev mode)
3. ACTIVE_HERMES_ROOT git checkout WITH .hermes-bootstrap-complete
marker -- the post-install fast path
4. `hermes` on PATH (CLI-installed user adding the desktop)
5. pip-installed hermes_cli via system Python
6. bootstrap-needed sentinel -> hand off to runBootstrap
Deletes the entire FACTORY_HERMES_ROOT / RUNTIME_MARKER /
syncTreeExcludingVenv machinery (-200 lines). The isGitCheckout
guard that bit us in the install.ps1 PR is gone.
First-launch bootstrap (electron/bootstrap-runner.cjs)
1. Resolve install.ps1: prefer SOURCE_REPO_ROOT/scripts (dev), else
download from GitHub raw at INSTALL_STAMP.commit (cached at
HERMES_HOME\bootstrap-cache\install-<sha>.ps1).
2. Fetch the stage manifest via install.ps1 -Manifest -Commit X
-Branch Y.
3. Iterate stages: install.ps1 -Stage <name> -NonInteractive -Json
-Commit X -Branch Y per stage.
4. On all stages green: write the .hermes-bootstrap-complete
marker with {schemaVersion, pinnedCommit, pinnedBranch,
completedAt, desktopVersion}.
Per-run log to HERMES_HOME\logs\bootstrap-<ts>.log. Cancellation
via AbortSignal. Manifest cache so retries don't re-download.
Install overlay (src/components/desktop-install-overlay.tsx)
Mounted alongside the existing onboarding overlay; flexbox card
with header (static) + middle (scrollable) + footer (failure-only,
static). Subscribes to hermes:bootstrap:event IPC + resyncs from
hermes:bootstrap:get on mount/reload. Renders:
- 14-stage checklist with per-stage state icons
- Overall progress bar + current-stage spotlight
- Auto-expanded installer-output panel on failure
- "Copy output" button (full ring buffer + error to clipboard)
- "Reload and retry" wired through hermes:bootstrap:reset to
clear main.cjs's latched failure
Synthetic empty-manifest event from main.cjs flips the overlay to
'active' immediately so the slow install.ps1 download doesn't
leave the user staring at the generic Preparing splash.
Failure latching (main.cjs)
bootstrapFailure module-scope variable holds the rejection after
install.ps1 fails. startHermes() throws the latched error
immediately when set, bypassing the entire ensureRuntime +
runBootstrap chain. Without this, the renderer's ensureGatewayOpen
retries would re-run install.ps1 in a 5-10 min hot loop while the
user was still reading the failure overlay. Cleared via
hermes:bootstrap:reset on user-driven retry.
Unsupported-platform overlay (1F)
macOS / Linux packaged builds (no install.sh stage protocol yet)
emit an unsupported-platform event with a copy-pasteable install
command + docs URL. Dedicated overlay branch with "Copy command"
+ "I've run it -- retry" buttons.
install.ps1 additions (Phase 1F.3 + 1F.5)
-----------------------------------------
New -Commit and -Tag string params. Precedence Commit > Tag >
Branch. Honoured by all three code paths (update / fresh clone /
ZIP fallback), with archive URL selection that handles each
ref-type variant. Detached-HEAD checkouts intentionally -- they're
pins, not branches the user pulls into.
EAP=Continue wrap around the new pin-step git invocations. `git
fetch origin <commit>` writes the routine 'From <url>' info line to
stderr; under the script's global EAP=Stop that terminates the
script even though fetch+checkout succeed. Matches the established
pattern in Install-Uv, Test-Python, _Run-NpmInstall.
Backend fix (hermes_cli/web_server.py)
--------------------------------------
CORS allow_origin_regex now accepts Origin: 'null'. Packaged
Electron loads index.html via file://; Chromium sets the WebSocket
upgrade Origin header to the opaque origin 'null', which the old
regex rejected with HTTP 403 before gateway_ws() ever ran. This
failure mode was masked in the older FACTORY_HERMES_ROOT
architecture because the resolver often found an existing hermes
on PATH with different binding behavior.
Security maintained: localhost-only bind keeps cross-machine pages
out; per-process session token still gates every authenticated
/api/ endpoint regardless of Origin.
Desktop QoL
-----------
DevTools is now enabled in packaged builds (F12 / Cmd+Opt+I).
Field-debugging trade-off: tiny attack surface increase versus
a much better support story when CSP / WS / theme issues surface.
NSIS prereq-check page deleted (-767 lines). The standard
Welcome -> License -> Directory -> InstallFiles -> Finish wizard
now installs without custom Python/Git/ripgrep detection -- those
prereqs are install.ps1's job at first launch.
Test infrastructure (Phase 1G)
------------------------------
apps/desktop/scripts/test-desktop.mjs rewritten as a cross-platform
bundle validator (was darwin-only and asserted on dead factory-
payload paths):
NEGATIVE: hermes_cli/main.py is NOT shipped (regression guard)
POSITIVE: install-stamp.json carries a real commit + branch
POSITIVE: node-pty native deps shipped under resources/native-deps
POSITIVE: renderer dist/index.html reachable (asar or unpacked)
New nsis mode and npm run test:desktop:nsis script.
Validated end-to-end on clean Win10 VM
--------------------------------------
Confirmed: NSIS installer drops Electron shell, app launches,
install overlay shows progress, install.ps1 clones the pinned
commit, 14 stages run to completion, marker written, backend
spawns, WebSocket connects, onboarding overlay asks for API key,
main UI loads, integrated terminal works.
Failures handled: bootstrap stays failed (no hot-loop retry),
"Copy output" gives actionable transcript, "Reload and retry"
explicitly re-runs install.ps1.
What's deferred
---------------
- MSIX wrapping (Phase 2): same Electron .exe under MSIX manifest
with runFullTrust, signed and submitted to Microsoft Store.
- install.sh stage protocol parity (Phase 2): once shipped, the
unsupported-platform overlay becomes drive-it-yourself and
macOS/Linux packaged installers gain feature parity with Windows.
- settings/helpers.ts: harden setNested against prototype pollution.
POLLUTING_PATH_PARTS check is now applied at every assignment site
(loop + leaf) and uses Object.defineProperty so CodeQL can see the
guard inline rather than via a helper function call.
- lib/markdown-preprocess.ts: rebuild the dangling-fence close regex
from a fence-char + length instead of marker.replace(...). The marker
is captured by `(`{3,}|~{3,})` so it can only be backticks or tildes,
but CodeQL was tracing tainted input text into the RegExp source and
flagging hostname dots from input as part of the pattern (false
positive js/incomplete-hostname-regexp on the test fixture URLs).
Reconstructing from a literal char breaks the dataflow.
- scripts/notarize-artifact.cjs: drop args from the run() rejection
message. Args carry --key-id / --issuer / key file path; the existing
outer catch already squashes errors to a generic line, but CodeQL was
flagging the args.join(' ') as clear-text logging of APPLE_API_KEY_ID.
Composer DOM-text-as-HTML alerts (composer/index.tsx:379, :547) are
already addressed in 4dd9732a9 — innerHTML assignment was replaced with
renderComposerContents which builds DOM via replaceChildren / append
text nodes (no HTML interpretation).
Make the desktop app's runtime layout match what scripts/install.ps1 and
scripts/install.sh produce, so a desktop-only user and a CLI-only user end
up with the same files in the same places and can share one install.
Layout
- ACTIVE_HERMES_ROOT = HERMES_HOME/hermes-agent (was: process.resourcesPath/hermes-agent, read-only)
- VENV_ROOT = HERMES_HOME/hermes-agent/venv (was: userData/hermes-runtime)
- desktop.log = HERMES_HOME/logs/desktop.log (was: userData/desktop.log)
- HERMES_HOME default: %LOCALAPPDATA%\hermes on Windows, ~/.hermes elsewhere
The packaged .app/.exe still ships a read-only payload at
process.resourcesPath/hermes-agent (FACTORY_HERMES_ROOT). On first launch
or after an installer-driven upgrade we sync factory -> active, then
provision the venv and run pip install -e . against the active root.
Key behaviors
- Pin HERMES_HOME in the spawned Python's env so get_hermes_home() resolves
to the same path resolveHermesHome() picked. Without this, Python falls
back to ~/.hermes on every platform - fine on mac/linux, a split-state
bug on Windows where our default is %LOCALAPPDATA%\hermes.
- Detect developer installs by .git presence at ACTIVE; never overwrite
a user's checkout via factory sync.
- Marker at ACTIVE/.hermes-desktop-runtime.json (schema v4) tracks
pyproject hash + factory version + runtime schema version. depsFresh
fast-paths when nothing changed.
- Dev (npm run dev) prefers SOURCE_REPO_ROOT over ACTIVE so devs run
their local edits, not whatever's under HERMES_HOME.
- Better error messages distinguish "no payload" from "no Python".
- Preserve a legacy ~/.hermes on Windows when no %LOCALAPPDATA%\hermes
exists, so users with prior pip/manual installs aren't orphaned.
pyproject.toml
- Promote fastapi, uvicorn[standard], ptyprocess (non-Windows), and
pywinpty (Windows) to main dependencies. The dashboard backend
(hermes dashboard) needs them at runtime; the previous lazy-import
fallback was a footgun for fresh installs.
- Empty the [pty] optional-extra; kept as a no-op back-compat alias for
any existing pip install hermes-agent[pty] invocations.
Drops the hardcoded BUNDLED_RUNTIME_REQUIREMENTS list in main.cjs - the
desktop now installs whatever pyproject.toml says, single source of truth.
Files
- apps/desktop/electron/main.cjs: runtime layout, HERMES_HOME pin,
factory->active sync, marker v4
- apps/desktop/scripts/test-desktop.mjs: track new venv location
- apps/desktop/README.md: new Setup, Runtime Bootstrap, and
Debugging sections
- pyproject.toml: fastapi/uvicorn/pty backends in main
dependencies; [pty] extra emptied
Tested locally on Windows: npm run dev boots cleanly, sessions land at
the new location, type-check + lint + test:desktop:platforms all pass.
Verified end-to-end on a fresh Win11 VM via dist:win installer.
Known gaps (filed as follow-ups, not in this PR):
- Skills not seeded on packaged installs (sync_skills only runs in
cmd_chat, not cmd_dashboard). Need to move to shared pre-dispatch.
- Git Bash not bundled or detected; agent's terminal tool errors out
with a useful message but desktop bootstrapper should pre-flight it.
- install.ps1 / install.sh should be decomposed into composable phase
libraries so the desktop bootstrapper can reuse them as a single
source of truth across all install surfaces.
The "No inference provider configured" auth error reaches the renderer through gateway error events, not the prompt.submit promise; the previous patch only caught the latter, so the error toast still surfaced and onboarding never opened.
Also strip credential-shaped env vars from the test:desktop:fresh sandbox so the packaged backend can't see provider keys leaking from the launching shell.
