MultiPatch vs Rompatcher

MultiPatch is a free macOS application for applying and creating file patches. It applies BPS, IPS, UPS, PPF, XDelta, BSDiff, and RUP (Ninja2) patches, and creates BPS, IPS, PPF, XDelta, and BSDiff patches. To apply one, users can select a patch file or drag it onto the application window, then choose the target file and where to save the result. The application identifies the format from the patch file extension, so that extension must be correct. BPS creation offers Linear and Delta modes: Delta patches are usually smaller, but take longer and require more memory. Creating UPS and Ninja2 patches is not supported. The maker says patching is built into the application rather than handled by external tools. Version 2.0 requires macOS 10.9 or later; older releases are available for Mac OS X 10.4 through 10.8. A separate basic command-line version can apply or create patches for scripts or terminal use. The application is GPL-licensed, while the bundled patching libraries have their own licenses.

Rompatcher is a free ROM patching tool for Linux and Windows, written in Rust. It applies patches and detects their formats automatically from their magic bytes. The listed formats are IPS, BPS, UPS, APS N64, APS GBA, EBP, RUP, PPF, xdelta and BDF, covering patch workflows for systems including Game Boy, NES, SNES, Game Boy Advance, Nintendo 64, PlayStation and PSP.

Checksum verification is optional and supports CRC32, Adler32 and MD5. Rompatcher can look up ROM hashes for more than 15 consoles through RetroAchievements. The project describes its patch writes as transactional, using atomic writes and rollback if an error occurs. Without an output path, the command places a file in a patched/ directory, based on the ROM name with .patched and its extension. The README reports approximately 27 microseconds to patch a 1 MB ROM in IPS format. Installation instructions use Cargo to build from source, and the listed license is MIT OR Apache-2.0. The project page states no pricing or usage limits.