Treat copy as product data
Source text, translator context, placeholders, tags, plural logic, and obsolete messages stay visible instead of disappearing into loose files.
Product-grade translation catalogs
Make translations part of your release process.
Ferrocat is a Rust-native catalog engine for teams that want localized copy to be reviewable, testable, and ready for runtime delivery. It keeps source text, translator context, validation, QA, and compiled payloads in one inspectable layer.
cargo add ferrocatWhy Ferrocat
A catalog engine, not another pile of translation files.
Know what is safe to ship
Run structured audits for missing translations, empty strings, stale target entries, ICU drift, metadata conflicts, and fuzzy flags before release.
Stay ready for AI translation
Keep machine-generated entries traceable with model, confidence, modified time, and a hash that clears stale metadata after human edits.
Keep runtime delivery predictable
Compile locale-resolved artifacts with stable keys and explicit fallback behavior instead of reparsing translator files in production.
Performance
Fast paths are designed, measured, and documented.
Ferrocat is designed for catalogs that grow with real products. Large translation sets get byte-oriented parsing, borrowed read paths, deterministic updates, structured diagnostics, runtime compilation, and benchmark coverage.
Byte-oriented scanning
PO parsing works directly on byte sequences, keeping the hot path tight for large catalogs.
Borrowed and owned APIs
Read-heavy paths can borrow from the input buffer. Mutation flows use owned catalog structures.
Benchmark fixtures
Parser, serializer, merge, combine, and runtime paths are measured against repeatable fixtures.
Standards where they help
Proven formats, one product workflow.
Ferrocat presents PO, ICU MessageFormat, and NDJSON as explicit choices instead of hidden implementation details. Use translator-friendly files when people need editing context, line-oriented records when teams need clean diffs, rich-message semantics when copy needs runtime values, and compiled artifacts when applications need fast loading.
Translator-friendly PO
- Storage
- Gettext PO
- Semantics
- Gettext-compatible plurals
Use the catalog shape many translation tools already understand, with comments, references, flags, and plural forms preserved.
Rich-message PO
- Storage
- Gettext PO
- Semantics
- ICU MessageFormat
Keep translator-facing PO files while authoring messages with placeholders, formatting, plurals, selects, and structural diagnostics.
Reviewable NDJSON
- Storage
- NDJSON
- Semantics
- ICU MessageFormat
Use one-message-per-line JSON records that are easier to review, merge, stream, batch, and hand to external systems.
Evidence
Quality is part of the catalog contract.
Start here
Pick the path that matches your question.
Get started
Install Ferrocat, parse your first catalog, and see the main product workflows.
OpenAPI surface
Choose between parsing, catalog updates, audit reports, runtime compilation, and rich-message diagnostics.
OpenPerformance
Benchmark methodology, fixtures, and performance history.
OpenPalamedes
See how the JS and TS framework can use Ferrocat as its shared catalog engine.
OpenArchitecture
ADRs and engineering notes behind semantic choices, storage modes, and hot paths.
OpenCatalog QA
Audit completeness, stale entries, ICU drift, metadata conflicts, obsolete entries, and visible fuzzy flags.
Open