Field session on a nested SvelteKit app surfaced a self-reinforcing leak:
localStorage is per-origin, two projects reused 127.0.0.1:5174, and a
React project's leftover cycling session was resumed inside the Svelte
project. Its checkpoints then materialized a ghost session in the new
project's durable store that kept reattaching after every discard, and a
stale adapter module 401'd on live.js, hiding the picker.
Four fixes:
- Server: only session-creating events (generate, steer) may mint a
journal. Progress events (checkpoints, mount acks, accept/discard) for
unknown ids are refused with 404 unknown_session and never enqueued, so
foreign browser state cannot create ghost sessions. Browser sends are
gated so progress never overtakes its own creating POST (the Go-time
checkpoint and generate are concurrent fetches; the first sweep caught
the out-of-order arrival breaking every SvelteKit flow). Steer
checkpoints now follow the steer event for the same reason.
- Browser: saved sessions carry the server's appRoot; a session stamped
by another project is dropped at load time. Unstamped legacy state is
caught by the unknown_session refusal, which clears local state and
re-arms the picker with an explanatory toast.
- SvelteKit adapter: the layout import carries a token-derived revision
query so a helper restart changes the module specifier and no Vite
client/SSR cache can serve an adapter with a rotated-out token;
live-inject --port reads the running helper's token from server.json
instead of writing an unauthenticated live.js URL; script load failures
log an actionable console error; and adapter removal is byte-exact
(the old regex swallowed the next line's indentation).
- live.mjs resolves surface briefs from appRoot, then contextRoot, then
repoRoot, matching context.mjs in nested-app repos.
Tests: server unknown-session rejection units, adapter revision/
byte-exact-removal units, and a foreign-session e2e scenario that seeds
another project's localStorage state and asserts it is cleared, no ghost
journal materializes, and picking still works.
AI-assisted (Claude Code).
Co-Authored-By: Claude Code <noreply@anthropic.com>
A ground-up hardening of live mode, driven by a production session in a
nested-app monorepo that hit six distinct failure classes. Full design
rationale in docs/LIVE-REWRITE-PLAN.md; every Codex-reported failure now
has a mechanical fix and a regression test.
Roots: live/roots.mjs resolves appRoot/repoRoot/contextRoot once at boot
(keyed on dev-server configs, not monorepo brand markers), persists a
manifest, and every live CLI re-anchors onto it at startup, so a helper
run from the wrong directory can no longer fork session state. Context
files are discovered upward to the git root.
Render truth: variant_mounted / variant_mount_failed events give the
journal per-variant mount state; failures reach the agent's poll queue,
raise a persistent error card with Retry (no more localStorage wipe), and
an attach probe names root/dev-server mismatches explicitly. The browser
rehydrates from the server when localStorage is gone.
Svelte: the scaffolder now parses with the app's own svelte 5 compiler.
Control flow survives (an each collection crosses the contract as one
structured prop), keyed each blocks hydrate synthetic keys, and anything
a detached preview cannot support falls back to source-preview instead of
shipping a wrong scaffold. Preview modules live in per-publish revision
directories, defeating stale transform caches.
Accept: CSS is reconciled, not appended. Matching selectors are replaced,
params bake from params.json kinds, the compiler's unused-selector pass
prunes superseded rules (pre-existing dead rules protected), a selector-
loss postcondition refuses any write that would drop hand-written rules,
and live-complete refuses to finish while live plumbing remains in source.
Also: framework registry (live/frameworks/) with a crash-safe injection
journal, session-store snapshot caching with read-only reads, protocol
enum consolidation, steer Send button, honest DESIGN-panel empty states.
Testing: new unit suites (roots, AST scaffolder, accept CSS, accept
pipeline, framework conformance); e2e now fails on preview-tree 404s,
proves computed-style mount for every variant, drives the Tune panel
through baked params, and injects failures (broken mounts, republish,
storage loss). New runtime fixtures: monorepo-nested-vite (repo root !=
app root) and vite8-sveltekit-stateful (each blocks + state). Nightly
full-matrix cron. An independent adversarial review pass preceded this
commit; its blocker and major findings are fixed and regression-tested.
This work was produced with AI assistance (Claude Code).
Co-Authored-By: Claude Code <noreply@anthropic.com>
Paul BakausandClaude Code