Blockchain Core Developer

cLabs is seeking a Blockchain Core Developer (or Senior Distributed Systems Engineer, if you will) to join our Blockchain Team. Our team is responsible of the Celo’s blockchain node.

Our node is based on go-ethereum software with several transformations (like the consensus engine) that make the Celo blockchain unique. Our main challenges are scaling the network, improving its security and resiliency; and adding new features to the Celo ecosystem that can only be done at the node’s level (like paying gas with an ERC20 token).

We work alongside other engineering teams within cLabs. This includes other platform teams such as the Primitives team, as we constantly access smart contracts as part of our operations, and collaborate with other teams to design and implement the right incentives for our validators and full nodes. We also partner with user-facing teams such as the Developer Tools teams, as a big part of our job is to make end users’ and contributors’ lives easier.

This is a role with wide exposure to many areas of the stack, and you’ll quickly get acquainted with all the moving parts in a modern blockchain project.

You will:

• Collaborate with teammates and design the Celo protocol


• Contribute to the Celo blockchain client (L1 and L2), making sure it works as expected


• Perform load testing and performance optimization, identifying bottlenecks and optimal parameters for healthy functioning of the chain


• Write documentation outlining the specifics of the Celo protocol

You have:

• Prior blockchain knowledge and development experience


• Golang, ideally familar with geth / optimism / erigon or other golang-based Ethereum clients


• Distributed systems design skills and development experience


• Good debugging skills and a good understanding of how to figure out why things behave in an unexpected way


• Good communication skills, both written and verbal


• Responsible attitude to work, strong work ethic


• BONUS: Solidity knowledge


• BONUS: Rust knowledge

cLabs (“Celo Labs”) started Celo in 2017 and is one of many contributors to the open source project Celo. cLabs builds financial technology to enable prosperity of all beings.

To build technology and products that are used and loved by people and solve real-world problems, we need to build a team with many different perspectives and experiences. We are an equal opportunity employer and value diversity at our company. We do not discriminate on the basis of race, religion, color, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status. We encourage candidates from all backgrounds to apply and always consider qualified applicants with arrest and conviction records, in accordance with the San Francisco Fair Chance Ordinance.