Crates Workspace Architecture (crates/)

Fish is composed of 27 modular Rust crates structured into clear architectural tiers.

Core Tiers

1. Foundation Tier:
   • fish-core: Manifest models, configuration, project discovery.
   • fish-graph: DAG models, lockless topological sort, query algebra.
   • fish-executor: Child process management, response files, middleware chains.
2. Storage & Caching Tier:
   • fish-cas: Content-Addressable Storage with ZSTD and FastCDC chunking.
   • fish-cache: Two-phase fingerprint cache and garbage collection.
   • fish-remote-cache: REAPI v2 client and TCP streaming cache.
3. Execution & Scheduling Tier:
   • fish-scheduler: Dynamic Lookahead Critical-Path scheduler, Chase-Lev work-stealing, and GNU Jobserver tokens.
   • fish-worker: Remote worker cluster execution and daemon loopback.
   • fish-sandbox: Linux eBPF syscall tracer and WASM hermetic isolation.
4. Toolchains & Backends (11 Crates + contract):
   • fish-backend-api: The shared EcosystemBackend contract (trait, BuildMode, Ecosystem).
   • fish-backend-rust, fish-backend-cc, fish-backend-go, fish-backend-ts, fish-backend-py, fish-backend-docker, fish-backend-java, fish-backend-dotnet, fish-backend-swift, fish-backend-dart, fish-backend-zig.
5. Security & Diagnostics Tier:
   • fish-security, fish-analytics, fish-incremental, fish-installer.
6. Application Tier:
   • fish-cli: Unified command-line interface, TUI dashboard, LSP server, backend registry.