Release Notes v1.5.1

Released 2026-06-01. View on GitHub.

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Castwright 1.5.1

A stability + hardening release. The bulk of this release hardens the Qwen3-TTS default from v1.5.0: it drives long-run sidecar memory pressure down to a survivable, self-recovering state, makes a Qwen→Kokoro fallback loud instead of silent, finishes the reused-voice / persona consistency work, and closes a default-mode LAN exposure. No data migration required.

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✨ Headline features

🔌 Default-bind to loopback (new)

A security fix that closes the 2026-05-31 review's top findings.

• In default mode the server now binds 127.0.0.1 only, so the unauthenticated API and the /workspace static mount (manuscripts, audio, state.json / cast.json) are no longer reachable from other machines on a shared Wi-Fi. The opt-in npm run start:lan mobile flow is unchanged; BIND_HOST=0.0.0.0 restores all-interface HTTP.

▶️ Resume generation (new)

• A one-click way to continue a book whose run was interrupted (queued chapters left over, nothing in flight). Opening a book still never auto-starts generation — this is the explicit recovery affordance.

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🔊 Generation reliability

• Long Qwen runs climbed host RAM until the server was OOM-killed mid-book. Now bounded by host-RAM reclaim on model unload, an RSS / committed watchdog, a /debug/memory readout, and a process-recycle keyed on committed-private memory.
• A crashed sidecar used to drop the in-flight book. Now it respawns on unexpected exit, the readiness gate polls through a respawn instead of failing fast, and the in-flight + queued chapters started during a recycle drain are recovered. The server is authoritative for queue completion.
• Recycles interrupted a chapter mid-render. Now crossing the memory soft-threshold drains and recycles cleanly between chapters, so a long book rides out the pressure without a dropped chapter.
• A Qwen book could silently downgrade to Kokoro. Now a /health handshake plus a loud per-chapter fallback gate (with a resident-model pill showing every loaded model) means a fallback is always visible, never silent.
• A local Qwen timeout was misreported as "Gemini rate-limited" and halted the whole book. Now a stalled chapter waits on the readiness gate and re-renders, then skips non-fatally if it can't recover.
• Non-narration chapters no longer queue or hang the parallel synth tail.
• CUDA-fragmentation OOM fixed via expandable_segments.

🎙️ Voice & cast

• Reused characters lost their designed voice / persona. Now reused characters keep their bespoke voice and persona — the voice / voiceStyle are denormalised at the link and auto-match write sites, and the designed persona is shown for reused characters.

🎧 Listening & recovery

• A failed chapter forgot its state on reload. Now it shows "Failed · reason" with Retry after a reload, plus a per-row "Generate this chapter" escape hatch and a "Generated " line on done rows.
• Per-book state.json auto-backup — a scheduled background sweep snapshots each book's state.json (daily / weekly, newest-N retained) with a manual restore picker in Account.
• Crash diagnostics — FATAL crashes and unhandled rejections are captured; a startup port collision now prints an actionable message instead of a cryptic stack.
• Assorted dark-mode contrast and cast-row layout fixes.

🏗️ Under the hood

• Qwen performance — token-budget batch packing is now the default (cap 32 / budget 3600) plus TF32 + high fp32-matmul precision; an overnight full-book run held aggregate RTF ≈ 1.04 (~realtime).
• Pre-commit scope filter + GPU-contention throttle — a staged-diff scope filter skips out-of-scope test legs, and a soft nvidia-smi probe lowers test concurrency when a run is hammering the box.
• Test reliability — broke a tts/index ↔ provider import cycle that intermittently failed the cross-OS gate; pinned with a re-export identity guard. Per-chapter RTF history table in the developer Worktrees view.
• Archived 56 shipped feature plans; filed a security review and its follow-up backlog.

Full changelog: v1.5.0...v1.5.1