scarlet sovereign systems private, local-first AI · Aotearoa New Zealand

AI that runs on your hardware.

We build private, local-first AI developer tools. The model runs on your machine; your code and data never leave it. No cloud, no token bill, no telemetry — bought once, yours to keep.

Sovereign doesn't mean cut off. It means you own the substrate and control what leaves it.

What we build

Crimson Codex

Code intelligence over MCP — your local agent reads, searches by symbol, and safely patches a repo, entirely on your machine. read more →

Crimson Analyst

Forensic toolkit for ML inference engines. It found a real, months-hidden quantisation bug in one session. read more →

Rapu

Private, ranked code search over your repo — single binary, zero telemetry, the index never leaves disk. read more →

all products →

How we work

Receipt before pitch. Every claim we make is backed by a number or a link — a benchmark, a commit, a write-up. We publish the engineering, not the marketing. The journal is where the real work gets shown: what broke, what we measured, what we fixed.

Principles

  • Local-first. Inference, indexing, and edits happen on your hardware. Nothing uploads by default.
  • Pay once. Tools you own, not subscriptions that hold your work hostage.
  • Pure-Rust engineering. Hand-rolled, dependency-light, fast. No bloat, no hidden cloud calls.
  • Honest by default. No fabricated metrics, no hype. If it isn't built yet, we say so.