Reseam

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Reseam applies community-built patches to Android apps. This repository is the engine behind it: the code that reads an app, runs patches on it, and signs the result. Reseam Manager, the reseam CLI, and the browser patcher on reseam.app all use it.

APK parsing, DEX editing, and signing are written in Rust. Patches are written in Kotlin. They run on the JVM on desktop, on Android's runtime on phones, and on CheerpJ in the browser.

Docs for patch authors and the CLI are at reseam.app/docs. Their sources are docs/ and crates/cli/docs/.

Layout

Path
crates/bytes	bounds-checked little-endian fields of binary formats
crates/storage	file-backed bytes and temporary storage
crates/journal	savepoints and undo records for state a patch run may take back
crates/dex	DEX parser, editor, and writer
crates/hermes	Hermes bytecode parser, editor, linker, and writer
crates/apk	APKs, split sets, APKM/XAPK, manifest, resources
crates/sign	APK Signature Scheme v2 signing
crates/fixtures	archives the workspace's tests build as input
crates/model	requests, results, events, and errors shared by every host
crates/patcher	bundles, patch planning and execution, the Kotlin bridge
crates/cli	the reseam command
sdk/	the application SDK, its BoltFFI bindings (sdk/native), and its WASI build (sdk/browser)
sdk-kotlin/	the reseam-sdk Kotlin package for Android and JVM apps
patch-api/	the reseam-patch-sdk Kotlin API patches are written against
gradle-plugin/	the Gradle plugin that builds bundles
app-runtime/	the runtime patched apps carry: settings, their screens, and the bundle registry
browser/	@reseam/browser, the engine for web pages
xtask/	code generation, packaging, and releases (cargo xtask)

Build

You need the Rust toolchain in rust-toolchain.toml, JDK 17 in JAVA_HOME, and the BoltFFI CLI at the version in .boltffi-version.

cargo xtask regen patch-api   # generate the Kotlin bridge
cargo xtask runtime           # build the patch runtime jar the engine embeds
cargo build --release -p reseam-cli

Building the Android and desktop SDK needs more toolchains; see sdk/README.md. The browser package has its own steps in browser/README.md.

Checks

cargo fmt --all --check
cargo clippy --workspace --all-targets -- -D warnings
cargo test --workspace --no-fail-fast
./gradlew spotlessCheck checkKotlinAbi

How to write code here is in AGENTS.md. How the engine and the patch API talk to each other is in docs/internals/boltffi.md.

Release

cargo xtask release <version>
git push --follow-tags

This sets the version, commits, and tags v<version>. CI then publishes the CLI, both Kotlin packages, and @reseam/browser at that version.

License

AGPL-3.0-or-later, with additional terms under section 7 in NOTICE. Vendored code keeps its own license; see REUSE.toml.