The launcher is the first thing every player sees, and for many games it's also the most hated part of the experience. A five-minute patch that re-downloads gigabytes of unchanged data is a self-inflicted wound.
Diff at the binary level
Instead of shipping whole files, ship the bytes that changed. Binary-diff algorithms let a 4GB update become a 40MB download when only a few assets moved.
- Content-addressed storage so identical chunks are never sent twice.
- Integrity checks to catch corruption and tampering.
- Atomic apply with rollback so a failed patch never bricks the install.
Make it feel instant
Prefetch the next patch in the background while the player reads the news feed. By the time they click play, there's often nothing left to download.