What are we all about?

We are a team of builders and researchers on a mission to empower enterprises and developers worldwide to access and build on decentralized systems.

Our expertise covers several domains: Ethereum and Starknet protocol engineering, layer-2, AI, cryptography research, protocol research, decentralized finance (DeFi), security auditing, formal verification, real-time monitoring, smart contract development, and dapps and enterprise engineering.

Working to solve some of the most challenging problems in the blockchain space, we frequently collaborate with renowned companies, such as Ethereum Foundation, Starknet Foundation, Gnosis Chain, Flashbots, Forta Protocol, Lido, EigenLayer, Open Zeppelin, RISCZero, Aleph Zero, and many more.

Today, we are a 350+ strong team working remotely across 66+ countries.

Are you the one?

We are looking for a passionate and skilled engineer to join our highly dynamic team.

You will be developing blockchain-based solutions that span across a wide spectrum of the web3 ecosystem, from protocol level engineering and smart contracts development to dapps and Enterprise/Financial applications that integrate with or are built on blockchain infrastructure.

This is a remote-first role. You will be working with a globally distributed team of talented engineers and researchers, as well as many leading industry partners.

You should be proficient in at least one or more general programming languages (refer to the skills section for details), as well as Smart Contract development, primarily Solidity. A deep understanding of the Ethereum blockchain, strong general engineering skills, and a firm grasp of computer science fundamentals are required. The ideal candidate would be a robust problem-solver with excellent attention to detail and effective communication skills. Familiarity with non-EVM blockchains, zk proofs, the DeFi landscape, and traditional finance would be advantageous.

Responsibilities include, but not limited to:

• Work on full-stack engineering solutions that integrate with or built on top of blockchains.
• Design and build applications on various blockchains
• Develop, test, and deploy secure smart contracts
• Debug and optimize smart contracts
• Extract and process data from the blockchain
• Develop scripts & tools to automate or improve blockchain interactions
• Collaborate with other engineers and teams, both internally and externally
• Stay updated with new developments and technology in the blockchain space

Technical Skills:

• Excellent programming skills in one or more of the following programming languages: C#, Go, TS/JS, Solidity, Rust, Python, Java, Kotlin, but will also consider other tech stacks.
• Proficient in a smart contract programming language (eg. Solidity, Cairo, MOVE) with extensive experience in developing complex smart contracts. Familiar with toolings such as Foundry, Hardhat or Remix.
• Ability to implement efficient algorithms and design complex data structures
• Understanding of good software architecture and engineering process
• Ability to write clean, testable, and maintainable code without over-engineering
• Deep understanding of Ethereum blockchain architecture
• Understanding of the DeFi landscape, such as lending protocols, AMMs, Perps and stablecoins
• Experience in developing off-chain applications that integrate with web3 protocols, using libraries such as Web3.js and ethers.js.
• Strong computer science background

Other Competencies:

• You need to be a self-starter, with the curiosity and drive to continuously improve.
• Excellent problem-solving and analytical skills, with attention to detail
• Strong written and verbal communication and collaboration skills
• Proficiency in English

Nice to have:

• Knowledge in Traditional Finance, and the intersection between traditional finance and blockchain, such as Tokenization.
• Experience with layer-2 solutions like Starknet, Optimism, zkSync, and Arbitrum
• Familiarity with blockchain data analytics tools like Dune and Nansen
• Knowledge of cryptographic primitives like hashing and signature schemes
• Familiarity with zk proof systems (ZK-STARK, ZK-SNARKs)
• Familiarity with formal verification methods for smart contracts
• Experience in front-end development with frameworks like React or Angular
• Familiarity with smart contracts auditing tooling/techniques (e.g Fuzzing, Symbolic execution, Static and Dynamic Analysis)
• Infrastructure / DevOps experience (eg. setup private networks)
• Ethereum core development experience

Perks and Benefits

• Professional Growth: Continuous learning opportunities and the chance to work with industry leaders.
• Fully Remote: Work from anywhere in the world.
• Flexible Working Hours: Manage your own schedule to balance work and life effectively.
• Competitive Compensation: Attractive salary plus equity options.

Keep up to date on what we are working on by following us on our social channels:

• Discord
• LinkedIn
• Twitter

Application deadline: December 15th CET

Bitrefill is the leading crypto e-commerce site worldwide, fostering a circular economy that allows people to opt out from the traditional banking systems and embrace freedom. We make it easy for people to live on crypto around the world.

Does this sound like something to you? Then keep reading :)

Your Mission:

As our Mobile App Developer, you will work on migrating the current web-based experience of Bitrefill into native mobile for iOS and Android. A large percentage of our users are mobile and your job will be ensuring that they have the best possible experience using Bitrefill on the app.

Relevant UX adaptations of the web-based flow will be done for the respective platforms as appropriate, as well as building out features only available on native apps, such as native login, inter-app communication, push notifications, and much more.

Our Tech Stack:

• Node/TypeScript
• React
• React Native
• MongoDB, MySQL

Your Responsibilities:

• Responsibility for the UX, functionality and speed of our app and commercial platform;
• Building and deploying new code, features and products, as well as maintaining and improving old code;
• Working closely with our Communications and Management Teams to ensure optimal prioritization and streamlined deployment;
• Being metrics driven - continuously evaluate that what we’re doing is working, helping users understand what Bitrefill is and how to best use it;
• Being able to understand and work with pre-existing codebase and navigate it independently;
• Be hungry to learn, fast to execute, do a lot with little, and care strongly about your product and users;
• Be a team player and a good friend who will contribute to our unpretentious culture.

You bring with you:

• You reside in: EU/Americas timezones
• You have a minimum of 3+ years of Mobile app development experience and 5+ years of general programming experience
• You have frontend development skills with a focus on React Native and TypeScript
• A strong digital portfolio that demonstrates the above
• Strong written and verbal communication skills

It’s a plus if you also:

• Have a big influence on the product, so a good sense of UX / design is a strong advantage;
• Crypto experience is not a requirement but a strong plus - we’ll teach you what you need to know, but you need to have a passion for the movement;
• Have an understanding of native languages (Swift, Objective-C, Java and Kotlin) and React Native Modules;
• Experience integrating third party services.

We Offer:

Bitrefill believes in the freedom to work remotely and offering our team members flexibility. We’ve built our entire business around this. Have no fear; you will never feel lonely, and you’ll have the chance to meet your coworkers in person at our biannual team retreats. Here are some reasons people choose us:

• To become part of a talented team with high ambitions for a world where crypto is money for everyday use
• A challenging workplace and a great education when it comes to everything involving cryptocurrency
• Besides a competitive salary, we offer outstanding perks and benefits to make your experience at Bitrefill the best:
  • Option to get paid in crypto - at Bitrefill we walk the walk!
  • Freedom to work from anywhere (with a reliable and strong internet connection)!
  • Computer with necessary accessories
  • Remote Workspace Allowance - Ergonomic chairs and desks are an important part of a good home office
  • Educational Allowance - 300€ per year + subscriptions on the most enrichment learning platforms in the market!
  • Biannual team retreats consist of two get-togethers every year (which means, get your passport ready!)
  • 25 paid vacation days + a number of days to spend on your own country’s national holidays!
  • Paid parental leave - here, your work adapts to your personal life, not the other way around!
  • Wellness Allowance - 600€ per year - important to get you moving when you sit all day in front of a computer!
  • Global Health Insurance - We want to give you wings so you can fly high but you have to be safe after all!

Application deadline: December 15th CET

Keep in mind that we will only start processing the applications once the deadline is over.

Disclaimer

Please be aware of potential recruitment scams. Bitrefill will never ask you for money during the recruitment process.

All our communication happens via our official/career site email addresses (@message.teamtailor.com, @bitrefill.com) and only after applying via Teamtailor Careers site.