Sign and verify RPI PICO UF2 firmware binaries

picosign is a Python boot tool for signing and verifying Raspberry Pi Pico UF2 firmware binaries.

Developed in python code.

The README is used to introduce the modules and provide instructions on how to install the modules, any machine dependencies it may have and any other information that should be provided before the modules are installed.

Table of Contents

• 🚀 Installation
  • Install using pip
  • Install using build
  • Install using py setup
  • Install using docker
• 📦 Dependencies
• 📁 Tool structure
  • ✨ Features
• 📊 Code coverage
• 🛠 Usage
• 📚 Docs
• 👥 Contributing
• 📄 Copyright and licence

🚀 Installation

Used next development environment

Currently there are four ways to install package

• Install process based on using pip mechanism
• Install process based on build mechanism
• Install process based on setup.py mechanism
• Install process based on docker mechanism

Install using pip

picosign is located at pypi.org.

You can install by using pip

# python3
pip3 install picosign

Install using build

Navigate to release page download and extract release archive.

To install picosign type the following

tar xvzf picosign-x.y.z.tar.gz
cd picosign-x.y.z/
# python3
wget https://bootstrap.pypa.io/get-pip.py
python3 get-pip.py 
python3 -m pip install --upgrade setuptools
python3 -m pip install --upgrade pip
python3 -m pip install --upgrade build
pip3 install -r requirements.txt
python3 -m build --no-isolation --wheel
pip3 install ./dist/picosign-*-py3-none-any.whl
rm -f get-pip.py

Install using py setup

Navigate to release page download and extract release archive.

To install picosign locate and run setup.py with arguments

tar xvzf picosign-x.y.z.tar.gz
cd picosign-x.y.z
# python3
pip3 install -r requirements.txt
python3 setup.py install_lib
python3 setup.py install_egg_info

Install using docker

You can use Dockerfile to create image/container.

📦 Dependencies

picosign requires next modules and libraries

• ats-utilities - Python App/Tool/Script Utilities

📁 Tool structure

picosign is based on OOP and Hexagonal Architecture.

Tool structure

    picosign/
         ├── core/
         │   ├── __init__.py
         │   ├── model/
         │   │   ├── __init__.py
         │   │   └── signature_data.py
         │   └── service/
         │       ├── engine.py
         │       ├── __init__.py
         │       ├── iservice.py
         │       └── isubprocessor.py
         ├── engine.py
         ├── infrastructure/
         │   ├── cli/
         │   │   ├── engine.py
         │   │   ├── icli.py
         │   │   ├── __init__.py
         │   │   └── setup/
         │   │       ├── bundle.py
         │   │       ├── dep_validator.py
         │   │       ├── dependencies.py
         │   │       ├── factory.py
         │   │       ├── __init__.py
         │   │       ├── keys.py
         │   │       ├── opt_validator.py
         │   │       ├── options.py
         │   │       ├── registry.py
         │   │       └── validator.py
         │   ├── command/
         │   │   ├── command.py
         │   │   ├── icommand_definition.py
         │   │   ├── icommand_executor.py
         │   │   ├── __init__.py
         │   │   ├── read_command_definition.py
         │   │   ├── read_command_executor.py
         │   │   ├── sign_command_definition.py
         │   │   └── sign_command_executor.py
         │   ├── config/
         │   │   ├── picosign.cfg
         │   │   └── picosign.logo
         │   ├── __init__.py
         │   └── subprocessor.py
         ├── __init__.py
         ├── py.typed
         └── setup/
             ├── bundle.py
             ├── dep_validator.py
             ├── dependencies.py
             ├── factory.py
             ├── __init__.py
             ├── keys.py
             ├── opt_validator.py
             ├── options.py
             ├── registry.py
             └── validator.py

     10 directories, 45 files

✨ Features

• Adds and reads textual signatures from 220-byte padding in the first 512-byte block of UF2 binaries.
• Validates UF2 block boundaries and magic header constants (0x0A324655, 0x9E5D5157).
• Provides a modular and extensible architecture based on OOP and SOLID principles.
• Includes command line interface (CLI) support via a command/executor structure.
• Robust validation of project bundles, dependencies, and options.
• High code quality with full type checking and 100% unit test coverage.

📊 Code coverage

🛠 Usage

Install package

pip3 install picosign

Prepare main entry point by downloading main.py or create your own.

wget -O main.py https://raw.githubusercontent.com/vroncevic/picosign/main/main.py

Embed signature into a UF2 firmware binary:

python3 main.py sign --file firmware.uf2 --signature "AUTHOR: Vladimir Roncevic | VERSION: 1.0.0"

Read signature from a UF2 firmware binary:

python3 main.py read --file firmware.uf2

📚 Docs

More documentation and info at

• picosign.readthedocs.io
• www.python.org

👥 Contributing

Contributing to picosign

📄 Copyright and licence

Copyright (C) 2026 by vroncevic.github.io/picosign

picosign is free software; you can redistribute it and/or modify it under the same terms as Python itself, either Python version 3.x or, at your option, any later version of Python 3 you may have available.

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