kami
d0ca479d4f
throttle() read lastRequestAt, awaited delay(), then wrote it back — a
TOCTOU race with no mutex or queue, under concurrency: 10. Ten jobs read the
same timestamp, slept the same duration and fired in the same tick, giving
up to ~10 req/s against MusicBrainz's 1 req/s policy and risking an IP
block.
Replaced the lastRequestAt map with a per-host { lastRequestAt, tail }
limiter; each call links onto that host's promise chain, so the
read-sleep-write critical section is serialized and N concurrent callers
space out by minIntervalMs. Chain rejections are swallowed so one failure
cannot poison the queue. Per-host rather than global, so other integrations
are not starved by MusicBrainz.
Measured: 5 concurrent same-host calls at 200ms -> 802ms (previously all in
one tick); 3 distinct hosts at 1000ms -> 0ms, confirming no cross-host
starvation.
musicbrainz.client caught HttpError and returned null at all 7 catch sites,
making a rate-limited MusicBrainz indistinguishable from "no data for your
library" while every job reported success. A shared logMbFailure() now logs
429 (and 503 whose body mentions a rate limit) at error, stating results are
INCOMPLETE. The error model is otherwise unchanged.
REVIEW-2026-07-30.md finding 8.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
muzick
A high-performance, distributed music orchestration and recommendation platform.
Overview
muzick is designed to manage a local music library while providing an "infinite vibe" listening experience. It bridges the gap between a local filesystem and advanced discovery engines through a tiered recommendation architecture.
Tech Stack
Frontend
- Framework: React
- Routing: TanStack Router
- Data Fetching: TanStack Query (with Look-ahead Buffering)
- State Management: Zustand (for Session/Vibe state)
- Styling: CSS Variables (Customizable Themes)
Backend
- Runtime: Node.js / TypeScript
- Framework: Fastify
- Task Queue: BullMQ (via Redis)
- Search: Typesense
Infrastructure & Data
- Database: PostgreSQL (Source of truth for metadata, relationships, and session state)
- Cache/Queue: Redis
- Audio Analysis: Essentia (via Worker processes)
- External Metadata: MusicBrainz, Discogs, LRCLib, Cover Art Archive
Core Concepts
- The Rolling Vibe: A continuous, evolving stream of music that uses a "Rolling Window" of tracks. It interleaves owned library tracks with high-probability "probation" tracks (external discoveries).
- The Dislike Lifecycle: A multi-stage state machine that protects users from accidental deletions while ensuring the library stays clean.
- Tiered Similarity: Instant metadata-based matches, followed by deep audio-feature similarity.
Getting Started
Prerequisites
- Docker & Docker Compose
Running Locally
docker-compose up -d