June 2, 2022 · Reading Time: 3 minutes

STARKs, StarkEx, and Starknet

Share this post:


  • STARKs enable blockchain scaling by efficiently proving the integrity of computations
  • StarkEx is an application-specific scaling engine
  • Starknet is a permissionless, smart contract Layer 2 network


STARKs (Scalable, Transparent ARgument of Knowledge) are a proof system that enables the proving and verification of computations. It allows processing a big computation, generating a proof for the computation’s correctness, and then verifying the proof in very few steps.

STARKs can play a key role in blockchain scalability by allowing large computations to be done off-chain, where it is cheaper, leaving only the verification, which requires a fraction of the computation, to be done on-chain. In other words, by performing very few steps on-chain, the verifier asserts the integrity of a much larger computation that was done off-chain.

Using STARKs, layer 2 solutions batch together and compute thousands of transactions, and then verify their validity on-chain with a single STARK proof. The cost of the on-chain process is split between all transactions in the batch. This results in Ethereum security and low gas cost per transaction.

The low computational cost will usher in a new class of applications that were previously not feasible on-chain. These properties make STARKs an excellent building block for improving user experience and reducing gas costs, all while maintaining the security of the Ethereum settlement layer.

StarkWare provides two solutions to scale Ethereum with STARKs: StarkEx and Starknet.


StarkEx is a framework for creating permissioned, application-specific scaling solutions. StarkEx is a toolbox of useful application flows that projects can use to achieve cheap off-chain computation. A STARK proof, attesting to the correctness of execution, is generated off-chain. Such a proof can include up to 12,000–500,000 transactions (depending on the transaction type). The proof is then sent to the STARK Verifier to be accepted on-chain. This means one verification for all the transactions — for an incredibly low amortized gas cost per transaction.

A few examples of the applications deployed on StarkEx are dYdX (perpetuals trading), Immutable and Sorare (NFTs — minting and trading), DeversiFi (spot trading), and Celer (DeFi Pooling).

StarkWare is continuously adding more application flows to StarkEx, following the market and its customers’ needs.


Starknet is a permissionless layer 2 network where any user or developer can deploy smart contracts developed in the Cairo language.

Comparable to the Ethereum smart-contract experience, inside of the Starknet ecosystem, your contract can interact with any other contract deployed on Starknet, allowing for richly composable protocols. Starknet contracts can also interact with Ethereum contracts via asynchronous message passing.

Unlike StarkEx, where applications are responsible for submitting transactions, Starknet sequencers batch transactions and send them to be processed and proved. (Starknet’s sequencers are currently operated by StarkWare with future plans to decentralize.) This means once applications deploy their Cairo contracts, they do not have to worry about running additional Operator infrastructure. Starknet supports the Rollup data availability mode, meaning the state of the rollup is written to Ethereum along with the STARK proofs.

A huge developer community is deeply engaged with the Starknet ecosystem, building apps, tools and infrastructure. Dozens of applications are already live on testnet — DeFi, games, voting, AI and more. More over, developer tools such as block explorer, local testing environment and framework, SDK’s in several languages and more, are being built by the Starknet Community. In addition, active discussions take place in the Shamans’ platform, featuring suggestions for improvements, potential features and best practices.

To Sum It Up

Both StarkEx and Starknet are STARK-based scaling solutions. Both provide scalability, low gas costs, and Security, but have different operating requirements and interoperability patterns. StarkEx might be the right solution for an application that is largely self-contained and fits into the APIs that StarkEx provides. Starknet might be better suited for a protocol that requires interacting synchronously with other protocols or has needs that go beyond what StarkEx offers.

STARKs have revolutionized how applications can be built on Ethereum. StarkEx and Starknet will continue to enable applications that were previously unviable and push the limits of what is possible on the blockchain.

This article was written in collaboration by Tim Gestson and the StarkWare team