A programming environment for cyberphysical programming. Runs on Linux (x86_64 and aarch64), macOS (Apple Silicon) and Windows (x86_64).

v0.9.0-beta is a large release. The highlights:

• LLVM 22 --- bumped from LLVM 17, fetched and built in-tree via CMake's FetchContent (no separate LLVM install required).
• ORC JIT --- replaces the legacy MCJIT, including DSP hot-swap and module tracking.
• s7 Scheme --- replaces TinyScheme as the Scheme interpreter.
• WebGPU graphics --- the OpenGL stack has been replaced with WebGPU via wgpu-native. Enable with -DEXTERNAL_SHLIBS_GRAPHICS=ON.
• Linux aarch64 --- first-class support, alongside macOS arm64, Linux x64 and Windows x64. All four platforms are tested in CI.
• Interactive REPL --- pass --repl for a linenoise-based REPL (Linux and macOS only).

Download the latest binary release for your platform, unzip it and run extempore (extempore.exe on Windows) from inside the extempore folder.

Then, set up your text editor of choice and away you go.

Note: the VSCode extension used to offer an Extempore: Download binary command for one-click setup. It hasn't been updated for v0.9.0 and may not work --- downloading the release manually is the safest option for now.

For more information, check out BUILDING.md.

Extempore's CMake build process downloads and builds all the dependencies you need (including LLVM). So, if you've got a C++ compiler, git, CMake >= 3.28 and Ninja, here are some one-liner build commands.

On Linux/macOS:

git clone https://github.com/digego/extempore && cmake -S extempore -B extempore/build -G Ninja -DASSETS=ON && cmake --build extempore/build -j$(nproc)

On Windows (adjust the generator for your VS version):

git clone https://github.com/digego/extempore && cmake -S extempore -B extempore/build -G "Visual Studio 17 2022" -A x64 -DASSETS=ON && cmake --build extempore/build --config Release

Note on build time: the first build takes ~10-30 minutes because LLVM is compiled from source. Subsequent builds reuse the cached LLVM artifacts under build/_deps/.

Note on ASSETS: the ASSETS build-time option (boolean, default OFF) is set to ON above. This will download the Extempore binary assets --- required for many of the examples, but adds a ~250MB download to the build process. If you'd rather not do that, and are happy with some of the examples not working, then set -DASSETS=OFF instead.

Note on running: the extempore binary locates its runtime files (runtime/, libs/, examples/) relative to the source tree at build time. Run it from the build directory (./extempore) rather than installing it to a system location.

Check out these videos:

• The Concert Programmer
• Interactive, distributed, physics simulation
• Programming in Time
• The Physics Playroom - interactive installation
• An old Graphics Demo
• A Programmer's Guide to Western Music
• Ben's livecoding gig videos

The Extempore core team is Andrew Sorensen & Ben Swift. Jim Kuhn contributed significant performance improvements, which are not reflected in the commit logs, but for which we are extremely grateful. Many others have contributed to Extempore's development (see the full list).

Extempore documentation can be found at https://extemporelang.github.io/docs/

You can also join the Extempore community:

• Extempore Google group/mailing list
• #extempore on chat.toplap.org (although not as well-monitored as the mailing list)

• Extempore: The design, implementation and application of a cyber-physical programming language
• Systems level liveness with extempore

Copyright (c) 2011-2026, Andrew Sorensen

All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

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2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

Neither the name of the authors nor other contributors may be used to endorse or promote products derived from this software without specific prior written permission.

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