Building dApps that Last: Why Cairo is the Winner Programming Language for Web3 Devs

“To understand the world, you must understand Cairo.”

This sentiment, often attributed to the Egyptian writer Naguib Mahfouz, speaks to the significant role the ancient city played in shaping global culture, politics, and history.

Now, a coding language of the same name is becoming just as essential to understanding the Web3 ecosystem. Like the city itself - a learning gateway to complex histories, Cairo, the coding language, is opening new doors in the decentralised world, driving innovation and accessibility.

But what makes Cairo unique compared to other programming tools? And why should Web3 developers invest time to master it?

What Does Cairo Do?

Cairo is designed to be a highly optimized provable programming language, and it just so happens that STARKs are great for scaling Ethereum, too, because verifying a proof takes less time than executing the program with the same inputs. Hence, Starknet is quite literally written in Cairo with the goal of scaling Ethereum and building Web3 applications.

Starknet enhances Ethereum’s scalability by enabling the network to handle a higher volume of transactions without the usual slowdown or high fees. It achieves this by posting only state differences to Ethereum and aggregating many Starknet state transition proofs together to create a single proof, meaning the proving cost is amortized across many users. This process relies on zero-knowledge proofs (ZKPs), allowing Ethereum to verify transactions securely without exposing each detail—similar to receiving a summary receipt.

By processing transactions in bulk and only sharing essential data with Ethereum, Starknet’s use of Cairo not only cuts costs but also improves transaction speed.

Use Cases for Cairo

Cairo’s efficiency and privacy features make it indispensable for several Web3 applications. In DeFi, Cairo enables platforms to manage high transaction volumes at a lower cost, making services more accessible. In the NFT space, Cairo supports the creation and transfer of digital collectibles with reduced transaction fees, enhancing market accessibility and scalability. Additionally, with Cairo a developer can efficiently verify other proving systems that already have privacy as a common feature.

While Cairo’s powerful capabilities make it essential for advancing Ethereum and Web3, its complexity presents a learning curve for developers. However, for those who master it, Cairo unlocks vast potential to drive the future of decentralised applications.

As a highly sought after niche skill,  Cairo is valued by like-minded individuals who share a desire to create long lasting applications that can drive mass adoption forward in a meaningful way. They also gain insight into Cairo’s distinct advantages when compared to more popular and traditional programming languages.

Cairo vs. Other Programming Languages

Take, for example, Rust.

With its performance, safety, and multi-platform capabilities, Rust is ideal for developers who want flexibility across blockchain platforms and other applications. However, Cairo is better suited than Rust for Ethereum scaling and specific blockchain applications because it was designed with these use cases in mind. Rust lacks Cairo’s specific capabilities for Ethereum scalability and privacy, like transaction bundling and ZKPs. Cairo’s integration with Starknet and Ethereum makes it a more specialized tool for developers focused on scaling and optimizing Ethereum-based applications. Rust is more versatile and flexible across various blockchain platforms, but it lacks the huge efficiency that Cairo delivers, which scales Ethereum.

Cairo vs. Solidity

As Ethereum’s primary language for creating smart contracts, Solidity is designed to handle individual transactions within the blockchain. Cairo complements Solidity by addressing Ethereum’s need for scalability, by being an efficient language to verify proofs of computational integrity. Cairo, being both a Smart Contract and programming language, means that it can be used for on-chain and off-chain operations. In comparison, Solidity cannot aggregate blocks together as it can’t be used outside the EVM.

By focusing on transaction scalability, Cairo enhances the performance of Solidity-based smart contracts, making the two languages complementary, with Cairo providing a crucial layer for handling high-volume blockchain activity with native computational integrity.

Cairo vs. Python

While Python is known for its versatility and ease of use across data science, machine learning, and web development, Cairo is a specialised provable language focused on scaling Ethereum. Python’s beginner-friendly design, readability, and flexibility make it ideal for general-purpose applications, but these strengths don’t translate to blockchain-specific needs. While Python is suited to various industries, Cairo’s performance is tailored to the demands of Web3, making it better equipped for blockchain scalability and transaction efficiency.

Cairo vs. C++/Java

C++ and Java are high-performance, general-purpose languages used in applications such as gaming and enterprise software, where speed and complex logic are required. However, Cairo, with its provable nature and modern compiler architecture, can, in the context of a sequencer, execute operations concurrently and is able to scale to thousands by aggregating execution proofs together, constraining them all against the same set of rules that Ethereum verifies. This gives Cairo great security, as someone can’t produce a block without it complying with the StarknetOS rules.

Cairo is also uniquely tailored for the Ethereum blockchain, specifically designed to handle the demands of decentralised finance and high transaction throughput. While C++ and Java excel in traditional, centralised environments. Cairo’s ability to be a developer-friendly provable language, manage bulk transactions off-chain, and verify them securely makes it a superior choice for blockchain scaling, where general-purpose languages like C++ and Java fall short.

The other aspect of C++ and Java is that they are antiquated with large user bases, and they want to keep the language mostly the same. This is where Cairo comes in as something different with the ability to adopt new ideas and technologies, further demonstrating its superiority.

Why Cairo Matters for Web3 Developers

Cairo is a top tier language when it is the right tool for the job, specifically if you want to scale Ethereum, but if you want super efficient (non-verifiable) memory safe programs then Rust should be your go-to. However, as demand for Ethereum applications grows, so does the need for solutions that reduce costs and improve speed—making Cairo a key player in the Web3 ecosystem.

Developers can overcome the limitations of traditional coding languages in blockchain and bring applications to life that operate at scale and at lower costs. While it may not yet be as widespread as other languages Cairo is crucial for the future of Web3. Just as Cairo, the city, is a bridge to understanding complex histories, Cairo, the coding language, is a bridge to a more accessible, efficient, and decentralised future.

Does it take time to master? Yes. Can you do it? We want you to.

But anything worth doing, anything that will set you apart from the mundane and make you great - requires dedication and effort.

Cairo was not built in a day. Web3 won’t be either. However, with a skilled team of developers, the future holds tremendous potential for a better society for everyone.