Byte-oriented scanning
PO parsing operates directly on byte sequences. No intermediate string allocations on the critical path.
Rust-native localization toolkit
Your localization layer shouldn't be the bottleneck.
Ferrocat brings Gettext PO workflows, ICU MessageFormat semantics, and JSON delivery into one Rust-native toolkit — with conformance evidence, benchmark discipline, and explicit architecture boundaries.
cargo add ferrocatWhy it's fast
Speed from structure, not shortcuts.
Every hot path in Ferrocat is Rust-native, byte-oriented, and shaped by profiling — not by porting legacy abstractions into a faster language.
Borrowed & owned APIs
Zero-copy borrowed access for read-heavy workloads. Owned structures when you need to mutate.
Profiling-driven iteration
Performance claims backed by real profiling sessions and published benchmark fixtures — not guesswork.
Three catalog modes
Storage and semantics stay explicit.
Classic Gettext
- Storage
- Gettext PO
- Semantics
- Gettext-compatible plurals
Stay close to traditional gettext catalogs and familiar msgid_plural workflows.
ICU-native PO
- Storage
- Gettext PO
- Semantics
- ICU MessageFormat
Keep translator-facing PO files while authoring richer ICU plural, select, and formatting messages.
ICU-native NDJSON
- Storage
- NDJSON
- Semantics
- ICU MessageFormat
JSON-friendly line-oriented storage for external systems and modern toolchains.
Proof, not vibes
Conformance and performance are part of the product surface.
Start here
Pick the path that matches your question.
Get started
Install, parse, serialize. Learn where the high-level catalog APIs fit.
OpenAPI surface
Choose between PO core, catalog workflows, and ICU helpers.
OpenPerformance
Benchmark methodology, fixtures, and performance history.
OpenArchitecture
ADRs and engineering notes behind semantic choices and hot paths.
Open