mirror of epic games' lore open source version control
  • Rust 83.6%
  • Python 12.7%
  • C 3.1%
  • HCL 0.2%
  • Shell 0.2%
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Filename Latest commit message Latest commit date
Mattias Jansson cb5b536be4 build: Pass the pre-commit clippy on Rust 1.99
## Summary

Fixes the pre-commit clippy failures on stable Rust 1.99.0, which the CI runners picked up on 2026-10-02. `cargo clippy --all-targets -- -D warnings --no-deps` failed on main from that point, so every change request's lint failed with it.

- `double_must_use` now treats the boxed future an `#[async_trait]` method returns as already must-use. async-trait 0.1.89 marks every such method `#[must_use]`, which failed lore-proto with 53 errors. async-trait 0.1.92 resolves the lint in its generated code (dtolnay/async-trait#303), and the workspace requirement moves to it. It builds on syn 3, so the lockfile adds syn 3.0.6 alongside syn 2.0.117; `deny.toml` allows multiple versions.
- The atomic `fetch_update` is deprecated in favour of `try_update`, its rename, stable since 1.95. The three uses switch to it.
- `mut_mut` now catches the `&mut &mut` that `progress_bar_internal_print!` passed to `write!`. The macro passes the reborrow instead.

No lint is allowed or reconfigured. Validated with the pre-commit clippy invocation and `cargo +nightly fmt --all --check` on stable 1.99.0.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Lore-RevId: 1460
Lore-Signature: bad645bdc14a5b20da86bc4c639c537a010c64b851cc583315b1ec9fc2af61b0
2026-10-02 11:32:44 +00:00
.cargo lore-revision: Read a binary metadata payload through the filesystem operation 2026-09-24 07:35:58 +00:00
.github contrib: Add a Helm chart for loreserver 2026-09-24 19:49:36 +00:00
contrib contrib: Add a Helm chart for loreserver 2026-09-24 19:49:36 +00:00
docs lore-revision: Fix a dirty added file removed before commit 2026-10-01 07:22:56 +00:00
lore lore: Hold each call's arguments once in its command's future 2026-09-29 17:26:30 +00:00
lore-aws lore-aws: MetadataMigrator should not attempt to migrate a Fragmented&Compressed fragment 2026-09-18 05:34:41 +00:00
lore-base lore-base: Spawn one task type per call site to reduce codegen and speed up builds 2026-09-25 19:46:27 +00:00
lore-capi lore-capi: Expose the link list staged as a C API entry point 2026-09-29 09:11:56 +00:00
lore-chaos-client lore-client: Run the CLI binary from the library instead of recompiling it 2026-09-25 14:24:58 +00:00
lore-client build: Pass the pre-commit clippy on Rust 1.99 2026-10-02 11:32:44 +00:00
lore-credential lore-server, lore-transport, lore-revision: Allow decoupling the user directory from the auth service 2026-09-23 14:22:00 +00:00
lore-error-set lore-error-set: Re-bless internal guard snapshots for the hidden root re-export 2026-08-28 11:24:06 +00:00
lore-error-set-macro lore-core: Group FFI error codes into blocks and keep them exit-code safe 2026-08-28 04:16:59 +00:00
lore-hashicorp Initial code copy from private repo 2026-05-29 18:50:20 +00:00
lore-integration-tests build: Pass the pre-commit clippy on Rust 1.99 2026-10-02 11:32:44 +00:00
lore-io lore-revision: Change file info to an enum to avoid boolean flag combinations that has no meaning 2026-09-12 15:40:06 +00:00
lore-macro lore: Hold each call's arguments once in its command's future 2026-09-29 17:26:30 +00:00
lore-notification lore-revision: Drain change walk before returning and correctly handle strong references in completion 2026-09-19 11:46:44 +00:00
lore-proto lore-server: Advertise the OIDC provider in the Environment response 2026-09-30 09:17:35 +00:00
lore-revision build: Pass the pre-commit clippy on Rust 1.99 2026-10-02 11:32:44 +00:00
lore-server build: Pass the pre-commit clippy on Rust 1.99 2026-10-02 11:32:44 +00:00
lore-storage lore-revision: Map the storage futures of the immutable wrappers, not await them 2026-10-01 12:20:44 +00:00
lore-telemetry lore-transport: Add a ClientIdentify opcode so QUIC clients report a user agent in traces 2026-09-07 11:35:28 +00:00
lore-transport lore-server: Advertise the OIDC provider in the Environment response 2026-09-30 09:17:35 +00:00
notices notices: resolve license text for base64-simd, vsimd, and rs-consul 2026-06-05 17:53:57 +00:00
scripts lore-revision: Fix a dirty added file removed before commit 2026-10-01 07:22:56 +00:00
vendor lore-revision: split filter into exclusion and descent queries 2026-09-02 13:10:37 +00:00
.dockerignore Initial code copy from private repo 2026-05-29 18:50:20 +00:00
.gitignore docs: Clean up ADR/LEP tracking docs numbering and status 2026-09-18 20:42:35 +00:00
.loreignore docs: Clean up ADR/LEP tracking docs numbering and status 2026-09-18 20:42:35 +00:00
.markdownlint-cli2.jsonc docs: add content_tabs hook for comment-delimited tabs 2026-06-12 20:50:31 +00:00
.pre-commit-clippy.py Add missing executable bit on precommit script and add missing entries to ignore file 2026-06-01 09:00:30 +00:00
.pre-commit-config.yaml lore-core: Migrate errors to use internal or forward for error propagation, and enforce correct usage 2026-08-28 04:01:54 +00:00
.rustfmt.toml Initial code copy from private repo 2026-05-29 18:50:20 +00:00
.vale.ini docs: add project level README, migrate Lore design doc, updated branding assets, and glossary 2026-06-05 22:47:33 +00:00
about.toml notices: resolve license text for base64-simd, vsimd, and rs-consul 2026-06-05 17:53:57 +00:00
build-helper.rs lore-base: Stamp the build version into finished artifacts post link 2026-09-25 08:43:00 +00:00
Cargo.lock build: Pass the pre-commit clippy on Rust 1.99 2026-10-02 11:32:44 +00:00
Cargo.toml build: Pass the pre-commit clippy on Rust 1.99 2026-10-02 11:32:44 +00:00
clippy.toml lore-base: Shrink the tokio blocking pool to a fixed two-thread vestige and unify the thread count calculations 2026-08-08 15:07:09 +00:00
CODE_OF_CONDUCT.md Initial code copy from private repo 2026-05-29 18:50:20 +00:00
CONTRIBUTING.md lore: Split the C API artifacts to be built in lore-capi 2026-09-25 09:19:17 +00:00
DCO Initial code copy from private repo 2026-05-29 18:50:20 +00:00
deny.toml Initial code copy from private repo 2026-05-29 18:50:20 +00:00
GOVERNANCE.md Add structured GitHub issue forms and PR template for triage intake 2026-08-18 13:24:10 +00:00
LICENSE Initial code copy from private repo 2026-05-29 18:50:20 +00:00
MAINTAINERS.md update MAINTAINERS to propose adding specialist maintainers 2026-06-23 21:51:30 +00:00
mkdocs.yml docs: add content_tabs hook for comment-delimited tabs 2026-06-12 20:50:31 +00:00
pyproject.toml scripts/test: mark the tests that need an instrumented loreserver 2026-09-21 17:22:09 +00:00
pyrightconfig.json Initial code copy from private repo 2026-05-29 18:50:20 +00:00
README.md docs: add public roadmap and crosslink to it across the docs 2026-06-17 11:11:32 +00:00
SECURITY.md update SECURITY to include link to Vulnerability Disclosure Program 2026-06-15 15:39:15 +00:00
uv.lock chore(deps): bump the dependencies group across 1 directory with 4 updates 2026-09-01 12:00:01 +00:00

Lore — open source version control by Epic Games

Lore

Next-generation open source version control

Download Lore  ·  Quickstart  ·  Read the docs  ·  Join the conversation

License: MIT Built with Rust

Table of contents

About Lore

Lore is an open source version control system designed for unprecedented scalability of both data and teams. It is optimized for projects that combine code with large binary assets, including games and entertainment, and caters for the needs of developers and artists alike.

Note

Lore is pre-1.0 and under active development. Interfaces, on-disk formats, and APIs may change between releases.

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Get started with Lore

  • Quickstart — install Lore and make your first commit by following the quickstart guide.
  • Read the docs — delve into Lore's ethos and architecture in the Lore documentation.
  • Have questions? — the FAQ covers licensing, supported platforms, production readiness, and how Lore compares to other version control systems.
  • See where Lore is headed — the roadmap lays out the big-rock features by time horizon, from scalable locking to an open source desktop client.
  • Join the conversation — chat with us and our community on Discord.

Or try it right now — install Lore and start a local server in demo mode:

macOS / Linux

curl -fsSL https://raw.githubusercontent.com/EpicGames/lore/main/scripts/install.sh | bash -s -- --demo

Windows (PowerShell)

$env:LORE_DEMO=1; irm https://raw.githubusercontent.com/EpicGames/lore/main/scripts/install.ps1 | iex

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Overview

  • Easy setup, on-demand scalability — Get started in local mode in minutes. Then, scale up as far and as fast as you need.
  • Fast and efficient processes — Scale without slowdowns, thanks to shared, reusable data and as-needed downloads.
  • Free branching — Quickly and easily create, manage, and sync branches to freely experiment, iterate, and release.
  • History you can trust — Confidently track and manage revisions with Lore's verifiable tamper-evident source of truth.
  • Intuitive interface — Enjoy complete one-to-one access to the full Lore functionality via the CLI.
  • Full-surface API — Extend, customize, and integrate Lore via C/C++, C#, Rust, Go, Python, or JavaScript.

Note

Lore is the built-in version control system for UEFN (Unreal Editor for Fortnite), but today's open source tooling can't yet talk to it: the UEFN build uses a proprietary compression format that can't ship with the open source project. We're actively moving UEFN onto an open compression format — the same one this open source project uses — to eliminate the gap between the two.

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Lore's architecture

Lore is a centralized, content-addressed version control system that represents repository state as Merkle trees and an immutable revision chain, optimized for binary-first storage, deduplication, and sparse/on-demand data hydration at scale. For the full model—on-disk formats, chunking internals, and the mechanics of the Merkle tree—read the system design doc.

Highlights

  • Content-addressed storage — Repository data is stored and referenced by content hash in a Merkle tree, enabling fast comparisons, integrity checks, and reuse across history and branches.
  • Immutable revision chain — A revision's hash signature is derived from its revision state, including parent revision hashes and contained data hashes, forming an immutable chain with cryptographic integrity.
  • Chunked storage for large files — Files are stored as reusable chunks with indexed lookup, reducing duplication and enabling efficient updates and transfer for large binary assets.
  • On-demand hydration and sparse workspaces — Workspaces can stay lightweight by fetching file data only when needed, so you don't have to download everything up front.
  • Centralized service with caching — A service-backed architecture uses caching in front of durable storage to scale throughput for large teams and repositories.
  • Lightweight branches and fast switching — Branches are lightweight mutable references, so creating and switching branches is low-overhead without duplication of underlying data.

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Lore's repositories

Lore spans a family of repositories: the core library, server, and CLI in this repository, plus a software development kit (SDK) for each supported language.

Repository Description Link
Lore Library, Server & CLI The core Lore library, the Lore Server, and the Lore CLI. You are here. View on GitHub
JavaScript SDK The JavaScript binding for the Lore API. View on GitHub
Python SDK The Python binding for the Lore API. View on GitHub
C# SDK The C# binding for the Lore API. View on GitHub
Go SDK The Go binding for the Lore API. View on GitHub

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Fully open source

We believe a truly open ecosystem is built collectively using open standards. Lore is fully open source under an MIT license, and we invite you to build the version control system of the future in the open. See CONTRIBUTING.md to get involved.

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Contributing

Contributions of every kind are welcome — code, documentation, bug reports, and reviews. Start with CONTRIBUTING.md for the development workflow, then read the Code of Conduct and the project governance model. New to the codebase? The good-first-issue label is a good place to start.

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License

Lore is released under the MIT License. See LICENSE for the full text. Copyright (c) 2026 Epic Games, Inc.

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Contact and community

  • Discord — chat with the team and community on Discord.
  • GitHub Issues — report bugs and request features through GitHub Issues.

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