Fastlanepatch CDN

Platform

Build to install, in five stages

Everything between your build server and a player's disk.

Buildyour CIChunkcontent-definedSignmanifestSeedCDN + peersApplyverified write

What chunking buys, per title

Real numbers from customer titles, anonymised.

Title typeBuild sizeNaive patchChunked patchReduction
Open world, weekly142 GB38.4 GB2.9 GB92%
Competitive shooter, biweekly62 GB19.1 GB1.4 GB93%
Live-service RPG, weekly88 GB24.0 GB3.1 GB87%
Racing, monthly104 GB41.2 GB6.8 GB84%
Strategy, patch-heavy34 GB8.2 GB0.4 GB95%

SDK

One header, one library

A C API with bindings for C++, C#, Rust and Unreal. No framework, no service to run alongside the game.

Bandwidth manners

Adaptive rate limiting that backs off when the player is in a match, plus hard caps you set per platform.

Verified writes

Chunks land in a staging area, get verified, then are applied atomically. A power cut mid-patch leaves a working install.

Publishing a build

publish.sh
# in your build pipeline
fastlane chunk ./build/win64 --title atlas --branch live
# 142 GB → 1.94 M chunks · 2.9 GB new vs previous build

fastlane sign --key-ref ci://fastlane-release
fastlane publish --title atlas --branch live --version 2026.8.1 \
  --seed-before 2026-08-11T16:00Z

# seeded to the CDN edge before the announcement