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Full stack developper



Software Engineering
Posted on Wednesday, June 5, 2024

Full stack developper

In progress

About Us


The emergence of verifiable computing is transforming the blockchain industry faster than expected. Applied Zero-Knowledge Proofs (ZKP) systems were merely envisioned a few years ago and nowadays have already facilitated billions of transactions.
While the initial applications of ZKP to the blockchain industry (especially Ethereum) relied on the development of low-level, complex, heavily customized solutions, recent technological advancements brought by Starkware, Risc Zero, Succinct, and others have allowed for a separation of concerns between engineering and proving. It is becoming possible to develop verifiable software without being a cryptographer oneself.


In this context, KKRT Labs stands as the very first company to develop a new generation Ethereum client that is verifiable by design, i.e., developed from scratch with a provable language (Cairo, from Starkware).
The project began in October 2022 as an open-source initiative accepting contributions from the community. It immediately garnered attention and support from prominent figures in the crypto community, including Vitalik Buterin himself.
To elevate the project, we incorporated the company in April 2023 and secured funding for the next five years. Banking on Starkware technology has allowed us to progress orders of magnitude faster than our competitors, and we are now on the verge of releasing our public testnet.


To support the growth of the Kakarot ecosystem by testing and fixing any issues found during a dapp lifecycle


create and lead the QA process, making sure all the reported issues are triaged, scheduled and solved
debug through the whole stack reported issues
build and maintain blockchain ecosystem related apps (bridge, faucet, ecosystem page)
maintain a close communication with the developers to make sure they feel listened and confident about Kakarot when facing an issue


Organization and planning: Plans, organizes, schedules, and budgets in an efficient, productive manner. Focuses on key priorities.
projects may report several unrelated issues simultaneously
the candidate should be able to quickly classify and prioritize the task to make sure they focus on the highest impact issues
Follow-through on commitments: Lives up to verbal and written agreements, regardless of personal cost.
it is of the utmost importance that projects willing to deploy on Kakarot feel listened to and acted upon
every single message of the candidat may be taken as a commitment on behalf of the whole company
Attention to detail: Does not let important details slip through the cracks or derail a project.
as bugs may arise at any place of the stack, a careful debugging is required to narrow down the scope of the issue and eventually finds it
Flexibility/adaptability: Adjusts quickly to changing priorities and conditions. Copes effectively with complexity and change.
issues may happen at any time and new issue be more prio that on-going ones
the candidate should be comfortable switching task on a daily basis and react quickly to important ones
Enthusiasm: Exhibits passion and excitement over work. Has a can-do attitude.
we know that it may be quite painful to debug problem all day long, even though there are always good learnings from it!
the candidate should keep a positive attitude whatever they face as complaining won’t get any bug solved
Communication: Speaks and writes clearly and articulately without being overly verbose or talkative. Maintains this standard in all forms of written communication, including e-mail.
the candidate should write post-mortem and communicate about them
Teamwork: Reaches out to peers and cooperates with supervisors to establish an overall collaborative working relationship.


Because we are constantly sharpening the saw, listed skills are nice-to-have but can always be learnt, so don’t feel afraid if you don’t have them all!
a strong experience with a frontend framework
typescript and node
experience with web3 related libraries (ethers.js, web.js) is a plus
good knowledge of docker related devops
experience with rust is a plus
language: the team is mostly french speaking but english is enough

What’s in it for you

By joining KKRT Labs, you will onboard on a journey at the frontier of verifiable computing, a new paradigm that is expected to change the way information is shared and used in the near future. You will contribute to the scaling of Ethereum, the leading applicative blockchain, and help decentralize whatever can be brought back to the people.
competitive package
international environment, working with people from all over the world with very different backgrounds
participation in international conferences at least 4 times a year; encouraged to be a speaker