Did you know that it is now possible to build blockchain applications, also known as decentralized applications (or “dApps” for short), in native Python? Blockchain development has traditionally required learning specialized languages, which has been a barrier for many developers… until now. AlgoKita comprehensive development toolkit for Algorand that allows developers to build blockchain applications in pure Python.
This article will walk you through the benefits of building blockchain applications, why Python is the perfect choice for dApp development, how to set up a blockchain development environment, and how to get started building secure blockchain applications in your own Python.
Why build blockchain applications?
Blockchain application development goes far beyond creating a decentralized database and peer-to-peer transactions. This opens up a new level of trust, security and efficiency for a variety of applications.
Guaranteed tamper-proof records: Blockchain creates an immutable and transparent ledger, ensuring data security and eliminating the risk of manipulation.
Automate complex agreements: Smart contracts and atomic swaps eliminate the need for third-party verification, streamlining transactions and reducing costs.
Revolutionize asset ownership: Digitization enables equity ownership and secure trading of real assets.
Create innovative solutions: Python development skills can be used to create groundbreaking applications in artificial intelligence, identity management, and secure IoT data sharing.
Why use Python to build blockchain applications?
Readability and maintenance: Python’s fluent syntax and robust tools make it easy to write, understand, and modify code, especially when working on complex, powerful blockchain projects.
Integration with other technologies: Python works well with other technologies that are often used alongside blockchain, such as web development frameworks and machine learning libraries. This allows for the creation of dApps that go beyond the core functionality of the blockchain.
World-class developer experience: Python has a large and active developer community, as well as first-rate comprehensive documentation and robust tools to support your Python and blockchain development journey.
How to set up a development environment to start building blockchain applications
The easiest way to build blockchain applications in Python is to download and install AlgoKit. This versatile toolkit empowers you to build, run and deploy secure, production-ready decentralized applications on the Algorand blockchain.
With AlgoKit, you can set up your development environment and project folder and start building your project with a single command.
Download and install the prerequisites
Make sure you have Python 3.12 or higher, pipx, Git, and Docker installed. On macOS, you’ll also need to install Homebrew.
Install AlgoKit
Open a command prompt/terminal and type “pipx install algokit”. This will install AlgoKit so you can use it in any directory.
Set up a local blockchain network
You can try the private version of the Algorand blockchain on your computer.
Type “algokit localnet start” in the command line/terminal. This will create a local blockchain network running in a container using Docker. You can then test the Docker Desktop application to see that it is running.
Type “algokit localnet explore” to launch a browser-based block explorer to visualize what’s happening on this local network.
Create a new project
Now that AlgoKit is installed, you can create a new project for your blockchain application.
First run “algokit init”. This will start a guided process and you will be asked to answer a few short questions to set up your project.
If this is your first time, start by selecting “smart contracts” to indicate that you are building a smart contract application.
Since you will be writing Python code, select “Python” as the language and choose a name for the folder that will hold all your project files and a name for your application.
Finally, select the Production template to set up a project ready for deployment.
A production template is like a pre-built starter kit for your Algorand project. This will give you a clear idea of how different parts such as testing, continuous integration/continuous delivery (CI/CD) and deployment work together in a complete Algorand project. Then select “Python” again.
Answer Y to the following questions to have AlgoKit install the dependencies and initialize the Git repository for you.
Once you have completed the project generation process, open the project directory in your favorite code editor.
How to build secure blockchain applications in Python
Study the code
The “Production” template will include a simple “Hello World” smart contract found in “smart_contracts/hello_world/contract.py”. This contract should look fairly familiar to Python developers, with a few key differences.
The first thing to note is that we are inheriting “ARC4Contract” for our “HelloWorld” class. ARC4 is an Algorand Request for Comment #0004 that defines a binary application interface (ABI) for Algorand methods. By inheriting from “ARC4Contract”, we ensure that the contract conforms to this standard, which is used by many tools in the Algorand ecosystem, including AlgoKit itself.
There is also a “@arc4.abimethod” decorator above the actual hello method definition. This decorator exposes this method as public under our contract. Since this is an ARC4 ABI method, any tool that supports the ABI can easily call this method. AlgoKit also includes a client generator that can generate a Python or TypeScript client to interact with any ABI methods you define.
Finally, you’ll notice that the argument and return type of our function is “arc4.String”. ARC4 also defines how we encode and decode data types when interacting with contracts. Since the Algorand Virtual Machine (AVM) does not support all the same features as the Python “str”, we need to use the “arc4.String” type provided by the “algopy” module.
Compile and build
You can use “algokit project run build” to compile a smart contract written in native Python into TEAL, a bytecode language that AVM can understand. Construction also creates additional artifacts that can be used to facilitate interaction with the contract, as we will see in the tests.
Interact and test
To see how the contract interacts and tests, go to “tests/hello_world_test.py”. Here you can see that we are using HelloWorldClient which was automatically generated by AlgoKit during the build phase. It allows very easy interaction with the contract and can be used in tests, backend or development frontend.
Write your code
After learning this project and running your first “Hello World”, you are ready to build on Algorand! You can turn the example contract into your own dApp, such as a marketplace, a manager of tokenized real assets, or an immutable on-chain data store.
Write the chained smart contract logic in contract.py and the associated tests in “smart_contracts/tests”. Run “algokit project run build” again to recompile, deploy and test the contract in seconds.
Now you’re ready to iterate quickly while building your own application, with AlgoKit taking care of boilerplate code and development environment configuration.
For more tutorials on how to use Python to build on Algorand with AlgoKitvisit AlgoDevs YouTube channel.
For more information about Algorand Python, refer to documentation.
