An API-first, offline-capable, agent-aware personal VCS.
Fervion is a next-generation version control system built for the AI era. It uses a content-addressed object store, scoped cryptographic boundaries, and first-class support for automated agents.
Fervion is paused, is not production-ready, and is not used in production. This repository is published as a source-available learning project and architectural reference for anyone who would like to study it.
The project progressed beyond an initial prototype. It includes a Rust Object Engine and Go API services for content-addressed objects, snapshots, compare-and-swap refs, immutable public refs, raw and semantic operation logs, scoped encrypted storage, key leases and rotation, tombstones, content-defined chunking for large files, offline queues, review gates, and a resumable promotion workflow. PostgreSQL migrations, protobuf contracts, local Docker Compose wiring, and test/smoke scripts are also included.
Much of this work is usable in local development, but important production work remains unfinished: production identity and secret-custody operations, review-signature and timestamp verification, promotion attestation, multi-replica deployment and routing, and offline reconciliation/semantic conflict resolution. See the technical plan for the precise implementation status and deferred work.
Fervion was deliberately designed not to be compatible with Git. Its API-first model, continuous history, scoped encryption, and agent-aware workflow differ from Git's object model and commit-based ecosystem. That made it difficult to compete with—or integrate smoothly into—the mature GitHub/Git tooling ecosystem without compromising the original design or rebuilding a very large amount of surrounding infrastructure.
I decided not to take it to production, but the project was still deeply worthwhile: it taught me a great deal about storage systems, cryptographic scope isolation, offline synchronization, cross-language service boundaries, and production-oriented engineering. I am sharing the code so others can read through the ideas, learn from the trade-offs, or take inspiration from parts of the design.
For an architectural overview, start with Vision, Architecture, and Technical Plan.
Built for maximum performance, safety, and reliability using a polyglot architecture:
- Core & Crypto: Rust
- Services & Networking: Go
- External Frontend UI: React + TypeScript in a separate client repository
- Storage: PostgreSQL + S3/MinIO
- Search: Meilisearch
Ensure workspace members are properly configured before building.
# Build the Rust IPC binary once before starting object-api or running smoke tests
cargo build -p object-engine --bin object-engine-ipc
# Test the Rust core crates
cargo test
# Test the Go API services
env GOCACHE=/tmp/fevion-go-build go test ./services/object-api/...Fervion is available under a custom Source-Available License. You are free to view and reference the code, but direct copying or redistribution is strictly prohibited without exclusive permission. See LICENSE for details.