This document explains how to harden your Tiny Tapeout projects locally, to speed up iteration times. The whole process should take roughly 10 minutes.
It uses the factory-test project as an example.
You need Python 3.11 or newer installed on your system. You can test which python version you have by running:
python3 --version
Note: On some systems, the python binary is called python and not python3.
If you have an older python version, you can install uv as an alternative.
You also need a recent version of Docker installed on your system.
We assume your project was cloned to ~/factory-test. If you don’t have a project yet, and want to follow these instructions to prepare your local setup, you can clone the factory-test repo by running the following command:
git clone https://github.com/TinyTapeout/ttihp25b-factory-test ~/factory-test
Clone the tt-support-tools repo (ttihp25b branch) inside the tt directory of your project:
cd ~/factory-test
git clone -b ttihp25b https://github.com/TinyTapeout/tt-support-tools tt
Create a dedicated directory for the virtual Python environment and initialize it:
mkdir ~/ttsetup
python3 -m venv ~/ttsetup/venv
source ~/ttsetup/venv/bin/activate
Or, if you are using uv:
mkdir ~/ttsetup
uv venv --python 3.12 ~/ttsetup/venv
source ~/ttsetup/venv/bin/activate
Then install the dependencies:
pip install -r ~/factory-test/tt/requirements.txt
Set up PDK_ROOT to the path of the directory that will contain the PDK. PDK and OPENLANE_IMAGE_OVERRIDE specify, respecively, the version of the PDK and the version of OpenLane 2 you will use:
export PDK_ROOT=~/ttsetup/pdk
export PDK=ihp-sg13g2
export OPENLANE_IMAGE_OVERRIDE=ghcr.io/tinytapeout/openlane2:ihp-v3.0.0.dev17
Note: the values of these values may change in the future - you can consult the tt-gds-action yaml for the latest values (look for the step named “Set up environment variables”)
pip install https://github.com/TinyTapeout/openlane2/releases/download/ihp-v3.0.0.dev17/openlane-3.0.0.dev17-py3-none-any.whl
git clone -b tt2025 https://github.com/TinyTapeout/IHP-Open-PDK $PDK_ROOT
Congratulations, you are ready to harden your project!
First, generate the openlane configuration file:
cd ~/factory-test
./tt/tt_tool.py --create-user-config --ihp
Then run the following command to harden the project locally. Notice that this command requires you to have Docker (or a compatible container engine) installed and running.
./tt/tt_tool.py --harden --ihp
It’s also recommended to run the following command, checking for any synthesis / clock warnings:
./tt/tt_tool.py --print-warnings
Once you set your environment, you can reharden at any time. Before running tt_tool.py, make sure to set the environment variables (as explained in step 1 above), and reactivate the Python virtual environment by running the following command:
source ~/ttsetup/venv/bin/activate
If you make changes to your project configuration (e.g. increase the number of tiles), you’ll need to update the openlane configuration file by running the following command in your project’s directory:
./tt/tt_tool.py --create-user-config --ihp
To reharden, run:
./tt/tt_tool.py --harden --ihp
cd test
pip install -r requirements.txt
make -B
cd test
pip install -r requirements.txt
TOP_MODULE=$(cd .. && ./tt/tt_tool.py --print-top-module)
cp ../runs/wokwi/final/pnl/$TOP_MODULE.pnl.v gate_level_netlist.v
make -B GATES=yes
Make sure you have the librsvg2-bin and pngquant packages installed:
sudo apt install librsvg2-bin pngquant
then you can use tt_tool to generate a render of the GDS as follows:
./tt/tt_tool.py --create-png
The resulting optimised PNG file is called gds_render.png (but note that other gds_render* intermediate files are also left behind).
For larger designs (or when close to maximum utilisation), routing can take a long time. If you have multiple CPU cores, you can try adding the following line to your config.json:
"ROUTING_CORES": 8,
to speed things up (replace 8 with the number of CPU cores in your system). Note you should not commit this change to git.