Yosys

Yosys Open SYnthesis Suite — a framework for RTL synthesis tools.

Table of contents
  1. About Yosys
  2. How to download
    1. x86_64
    2. aarch64 (ARM64)
    3. Verify the download
    4. Requirements
  3. How it is built
    1. Trigger and inputs
    2. Build matrix
    3. Step by step
    4. Testing
  4. Build summary

About Yosys

Yosys is an open-source framework for RTL (register-transfer level) synthesis. It has extensive Verilog-2005 support and provides a set of synthesis algorithms for a range of application domains, from FPGA flows to ASIC flows. It is also commonly used together with other tools such as ABC (for logic optimisation and technology mapping) and open-source place-and-route tools.

This is an unofficial repackaging. Yosys is developed by YosysHQ and its contributors. Bugs in Yosys itself should be reported upstream; packaging problems belong in this repository’s issue tracker.

How to download

Each Yosys version is published as its own tagged release, named yosys-v<version>. Files are named:

yosys-<version>-<arch>.AppImage
yosys-<version>-<arch>.AppImage.sha256

where <arch> is x86_64 or aarch64.

x86_64 

wget https://github.com/MrAbhi19/open-eda-appimage/releases/download/yosys-v0.69/yosys-0.69-x86_64.AppImage
chmod +x yosys-0.69-x86_64.AppImage
./yosys-0.69-x86_64.AppImage --version

aarch64 (ARM64) 

wget https://github.com/MrAbhi19/open-eda-appimage/releases/download/yosys-v0.69/yosys-0.69-aarch64.AppImage
chmod +x yosys-0.69-aarch64.AppImage
./yosys-0.69-aarch64.AppImage --version

To get another version, replace 0.69 (in both the tag and the filename) with the version you want. All versions are listed on the releases page.

Verify the download

Download the .sha256 file from the same release into the same directory, then:

sha256sum -c yosys-0.69-x86_64.AppImage.sha256

Expected output:

yosys-0.69-x86_64.AppImage: OK

The SHA256 is also printed in each release’s notes.

Requirements

  • Linux x86_64 or aarch64
  • glibc 2.35 or newer (Ubuntu 22.04+, Debian 12+, Fedora 36+, or equivalent)
  • FUSE 2 for direct execution (libfuse2 on Debian/Ubuntu, fuse2 on Fedora). Without FUSE, run with --appimage-extract-and-run.

Note: Yosys 0.67 is reserved for verification and experimentation with new packaging methods. Please don’t install it for regular use.

How it is built

Everything happens in the build-yosys-appimage.yml workflow on GitHub-hosted runners. No step is performed by hand.

Trigger and inputs

The workflow is started manually (workflow_dispatch) with these inputs:

Input Purpose Default
version Yosys version to build (e.g. 0.69) 0.69
make_latest Mark the release as GitHub “Latest” true
create_release Publish a GitHub Release (otherwise only a workflow artifact is produced) true

Build matrix

Each architecture is built natively (no cross-compilation, no emulation):

Architecture Runner
x86_64 ubuntu-22.04
aarch64 ubuntu-22.04-arm

Ubuntu 22.04 is used deliberately: it ships glibc 2.35, which sets the minimum glibc for the resulting AppImage. The job timeout is 30 minutes.

Step by step

1. Install build dependencies

sudo apt-get update
sudo apt-get install -y \
  cmake ninja-build gawk git make python3 lld bison clang flex \
  libffi-dev libfl-dev libreadline-dev pkg-config \
  tcl-dev zlib1g-dev graphviz xdot \
  wget curl file desktop-file-utils \
  python3-pil

python3-pil is used only to generate the placeholder icon; file and desktop-file-utils are used by linuxdeploy.

2. Download the official source tarball

The workflow uses the release tarball published by YosysHQ, not a git clone, so the source is exactly what upstream released:

wget -q https://github.com/YosysHQ/yosys/releases/download/v<version>/yosys.tar.gz
tar xf yosys.tar.gz
test -f CMakeLists.txt && echo "Source looks good"

3. Configure with CMake + Ninja

cmake -B build -G Ninja . \
  -DCMAKE_BUILD_TYPE=Release \
  -DCMAKE_INTERPROCEDURAL_OPTIMIZATION=ON \
  -DCMAKE_INSTALL_PREFIX=/usr \
  -DYOSYS_WITHOUT_EDITLINE=ON \
  -DYOSYS_WITHOUT_SLANG=ON
Flag Why
-G Ninja Fast parallel build backend
CMAKE_BUILD_TYPE=Release Optimised build
CMAKE_INTERPROCEDURAL_OPTIMIZATION=ON Enables link-time optimisation
CMAKE_INSTALL_PREFIX=/usr Standard prefix, so Yosys finds its share files (/usr/share/yosys) relative to the binary inside the AppImage
YOSYS_WITHOUT_EDITLINE=ON Drops the editline dependency; the interactive shell uses readline instead
YOSYS_WITHOUT_SLANG=ON Drops the optional Slang SystemVerilog frontend to keep the bundle small and portable

4. Build

cmake --build build --config Release --parallel $(nproc)

5. Install into an AppDir

cmake --install build --prefix AppDir/usr --strip

--strip removes debug symbols from the installed binaries. The result is a standard AppDir/usr/{bin,share,...} layout.

6. Create the desktop entry and icon

A yosys.desktop file is written to AppDir/usr/share/applications/:

[Desktop Entry]
Name=Yosys
Exec=yosys
Icon=yosys
Type=Application
Categories=Development;Electronics;
Terminal=true
Comment=Yosys Open SYnthesis Suite

AppImages require an icon, so a plain 256×256 RGBA PNG (solid blue, 30,100,200) is generated with Pillow and saved to AppDir/usr/share/icons/hicolor/256x256/apps/yosys.png.

7. Package with linuxdeploy

Tool Version
linuxdeploy 1-alpha-20251107-1 (pinned release, per-architecture AppImage)
AppImage output linuxdeploy’s built-in appimage output, bundled with that linuxdeploy release
Compression zstd (OUTPUT_APPIMAGE_COMP=zstd)

linuxdeploy is downloaded from https://github.com/linuxdeploy/linuxdeploy/releases/download/1-alpha-20251107-1/linuxdeploy-<arch>.AppImage, where <arch> is x86_64 or aarch64. Pinning the release keeps builds reproducible.

export OUTPUT_APPIMAGE_COMP=zstd
./linuxdeploy-<arch>.AppImage \
  --appdir AppDir \
  --executable AppDir/usr/bin/yosys \
  --desktop-file AppDir/usr/share/applications/yosys.desktop \
  --icon-file AppDir/usr/share/icons/hicolor/256x256/apps/yosys.png \
  --output appimage

linuxdeploy inspects yosys, copies every shared library it depends on (Tcl, readline, libffi, zlib, the C++ runtime libraries, and so on) into AppDir/usr/lib, then produces a single squashfs-based AppImage. The output is renamed to yosys-<version>-<arch>.AppImage.

8. Smoke test

chmod +x yosys-<version>-<arch>.AppImage
./yosys-<version>-<arch>.AppImage --version

9. Checksum

sha256sum yosys-<version>-<arch>.AppImage > yosys-<version>-<arch>.AppImage.sha256

10. Publish

  • The AppImage and its .sha256 are uploaded as a workflow artifact (actions/upload-artifact).
  • If create_release is enabled, they are attached to a GitHub Release tagged yosys-v<version> using softprops/action-gh-release. The release notes include the SHA256 and quick-start instructions.
  • Both architectures upload to the same release tag.

Testing

A separate workflow, test-yosys-appimage.yml, downloads the published AppImage on clean ubuntu-22.04 (x86_64) and ubuntu-22.04-arm (aarch64) runners. It fetches the picorv32 RISC-V core and runs:

read_verilog picorv32.v
synth -top picorv32
stat

This exercises the full read_verilog → synth → stat flow using only the AppImage. It is run manually and takes the Yosys version as an input.

Build summary

Item Value
Source Official yosys.tar.gz release tarball
Build system CMake + Ninja
Build type Release, with LTO
Disabled features editline, Slang
Runners ubuntu-22.04, ubuntu-22.04-arm
Bundler linuxdeploy 1-alpha-20251107-1
AppImage compression zstd
Minimum glibc 2.35
Release tag yosys-v<version>
Artifacts yosys-<version>-<arch>.AppImage + .sha256

Unofficial repackaging. Each tool retains its upstream license.

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