incr

Quick Jump: Quick Start | Setup | Benchmarks | Citing | License & Contributing

Bolt-on incremental execution for the shell. Incr wraps shell commands to track their file dependencies and memoize their results, so that unchanged commands are skipped on re-execution and their outputs are replayed from cache.

Setup

The default path is Docker. Clone the repo, then run Incr through the top-level incr wrapper:

git clone https://github.com/atlas-brown/incr
cd incr
make install
incr ./evaluation/hello-world.sh

The wrapper runs ghcr.io/atlas-brown/incr:latest by default.

If you prefer native setup on Ubuntu 22.04, install the dependencies manually.

See INSTRUCTIONS.md for full evaluation instructions.

Docker

docker run -it --rm --privileged ghcr.io/atlas-brown/incr:latest

Toggle DEBUG and DEBUG_LOGS in src/config.rs for debug output.

Manual Installation

Native installation is optional. On Ubuntu 22.04, you need these packages installed:

• git
• mergerfs
• strace
• python3
• python3-pip
• build-essential
• pkg-config
• libssl-dev
• libtool
• Rust via cargo

Then clone and build Incr:

git clone https://github.com/atlas-brown/incr
cd incr
pip3 install --no-cache-dir -r requirements.txt
cargo build --release

To use the Docker wrapper from your PATH, run:

make install

To use Incr natively from the checkout, run:

bash ./src/incr.sh myscript.sh

Quick Start

To sanity-check the install with a minimal example:

incr ./evaluation/hello-world.sh

This should print the same Hello, world!-style output as the underlying shell script, while exercising the Docker-backed incr entrypoint.

Benchmarks

See INSTRUCTIONS.md for full benchmark setup and the behavioral-equivalence harness.

Citing Incr

If you use Incr or build on any component in this repository, please cite the following paper:

@inproceedings{incr:osdi:2026,
  title = {Incr: Faster Re-execution via Bolt-on Incrementalization},
  author = {Xie, Yizheng and Lamprou, Evangelos and Xia, Jerry and Vasilakis, Nikos},
  booktitle = {20th USENIX Symposium on Operating Systems Design and Implementation (OSDI 26)},
  year = {2026},
  publisher = {USENIX Association},
  tags = {performance}
}

License & Contributing

Incr is an open-source, collaborative, MIT-licensed project developed by the ATLAS group at Brown University. If you'd like to contribute, please see CONTRIBUTING.md — contributions, bug reports, and reproducibility feedback are welcome.