We build tools for the code the world can't rewrite.
Se.Fier is a systems and language-engineering company. Our mission is to give the world's COBOL estate a safe, modern future — without asking anyone to re-derive decades of hard-won business logic.
The mission
Billions of lines of COBOL move trillions of dollars a day. The people who wrote it are retiring, and the platforms that run it are getting harder to justify. We believe the answer is not a risky rewrite, but a mechanical, verifiable port — preserving the logic exactly while moving to a memory-safe language and commodity hardware.
The approach
Accuracy before everything. Our five guarantees — accurate, reliable, secure, fast, and
maintainable — are the acceptance criteria for every component. We prove them with
differential testing, fuzzing, and a zero-unsafe codebase, on every commit.
Precision, not shortcuts.
Fidelity
Byte-for-byte, or it's not done. No "close enough" behavior for financial and public-sector systems.
Safety
Memory-safe by construction. Zero unsafe. Deterministic, panic-free runtime paths.
Craft
Maintainable, idiomatic code — the ported Rust is something a modern team is proud to own.
Let's modernize something critical.
We partner with banks, insurers, and public agencies to pilot migrations on real COBOL estates.
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