Lore: Epic Games opens up a version control system built for huge binary assets

Epic Games has published Lore, an open source version control system it describes as designed for "unprecedented scalability" of both data and teams. The project targets workloads that code-centric tools handle awkwardly: games and entertainment productions that mix source code with very large binary assets, and where artists work alongside engineers.

A centralized, content-addressed design

Lore is a centralized, content-addressed version control system that represents repository state as Merkle trees and an immutable revision chain. Data is stored and referenced by content hash, which the project says enables fast comparisons, integrity checks and reuse across history and branches. Large files are stored as reusable chunks with indexed lookup, so transfers and updates avoid duplication, while workspaces stay lightweight through on-demand hydration and sparse checkouts. A service-backed architecture puts caching in front of durable storage to scale throughput for large teams and repositories, and branches are lightweight mutable references rather than copies of data.

Status: a pre-stable 0.x release

The release is explicitly pre-stable: APIs and protocols may still change before 1.0, though Epic says data written into Lore is designed to remain readable by every future release. It runs on Windows, macOS (ARM64) and Linux (x86-64 and ARM64), with a library interface usable directly from C/C++ and Rust and bindings for JavaScript, C#, Python and Go; a Docker image is provided for server deployment. Local use needs no infrastructure at all — a zero-config local mode runs as a single executable — while team deployments use replaceable storage backends, with AWS S3 and DynamoDB as reference implementations behind documented interfaces.

Already running inside Fortnite's editor

Lore is not a greenfield experiment. Formerly called Unreal Revision Control, it is the built-in version control system for UEFN, Unreal Editor for Fortnite, where creators already use it to version their islands. Epic says internal teams are adopting it progressively and that Lore is being implemented as the backing store for the UEFN cook pipeline, replacing intermediary storage layers and cutting the time between publishing a change and playing it. File locking exists but is deliberately limited: locks inform collaborators rather than block edits, and lock state is queried across the whole repository. An early desktop client ships as a binary but is not open source yet.

MIT licence and an open roadmap

Lore is released under the MIT licence, and Epic says contributors must have equal access to features as its own engineers, with no hidden or paywalled core functionality; contributions use the Developer Certificate of Origin rather than a CLA. Planned work includes a virtual file system, Windows service support, OAuth, scalable locking, multi-server replication, hooks, a VS Code plugin and open source desktop and web clients. Governance is meant to evolve toward a technical steering group drawn from internal and external contributors.