Compiler Engineer in Test
Full time
Remote
Compensation is not specified
Role
QA Engineer
Work Experience
Less than 1 year
Description
At Matter Labs, we believe freedom drives progress and prosperity. We don’t see ourselves as a company, but as a team aligned around a single mission: to advance personal freedom for all (see ZK Credo).
To achieve this goal, we’re building zkSync — a credibly neutral, fully open source technology stack and network on top of Ethereum, which is owned and governed by its community. We use advanced cryptography called zero-knowledge proofs to scale Ethereum infinitely without compromising on security or decentralization. With a world-class team, a community of over 1M supporters across Twitter + Discord, and hundreds of millions $ in funding, we have abundant resources to accomplish the mission.
The Product
Previous compilers for smart contracts were usually written from scratch. That meant reinventing the wheel, a poor optimization pipeline, and lack of tools. We aim to fix this and deliver production-quality toolchains and a better development experience to our customers. That’s why we use LLVM, follow LLVM development practices, and upstream our fixes. In particular, we strongly prefer to reuse well-written and decently-tested code.
The Role
Doing even better testing is where you come in. Smart contract compiler bugs can cause our customers to lose currency, so thoughtful and comprehensive testing is essential. Complete testing of a blockchain programming language is impossible, so the ability to plan and prioritise the most important areas to test is crucial. Enjoyment of software testing and bug filing is required.
What You'll Be Doing
- Adapting and/or creating compiler correctness tests
- Maintaining and supplementing testing infrastructure
- Contributing to, and criticizing, test plan(s).
- Requirements collection and documentation criticism.
- Working with developers to decide how each feature is best validated.
- Implementing test cases.
- Identifying and reporting weaknesses in current processes.
- Initial investigation of correctness and performance issues; efficiently isolating, clearly reporting, and diligently tracking bugs
Skills Required
Matter Labs
Website
zksync.ioCompany size
Not specified
Location
United States
Description
Not specified
David Rutkovsky
Chief Technology Officer (CTO) / Senior Full-Stack Developer (Web3)
London, UK
London, UK
Full time
Remote
About the Role
We are building a next-generation Web3 social platform designed to redefine how digital communities connect, collaborate, and grow.
Backed by years of experience within the cryptocurrency, blockchain, and digital asset ecosystem, our team has developed deep insights into how founders, developers, investors, creators, and communities interact. This understanding inspired us to create a platform that goes beyond financial applications and focuses on empowering meaningful social engagement.
Our mission is to build a transparent, community-driven social network where users can share ideas, collaborate on projects, discover opportunities, and create lasting relationships. We believe the next evolution of social media will be powered by decentralized technologies while maintaining an exceptional user experience, simplicity, and long-term sustainability.
We are seeking an experienced Chief Technology Officer (CTO) or Senior Full-Stack Developer who is passionate about Web3 and capable of leading the technical vision, architecture, and execution of our platform from the ground up.
Responsibilities
Lead the technical strategy and product architecture.
Design and build scalable backend systems and modern frontend applications.
Develop high-performance APIs and real-time features.
Integrate blockchain technologies, wallets, and Web3 authentication where appropriate.
Build secure, reliable, and maintainable infrastructure.
Collaborate closely with product, design, and leadership teams.
Establish engineering best practices, code quality standards, and development workflows.
Mentor engineers and help grow the technical organization.
Evaluate emerging technologies and implement solutions that improve scalability, security, and user experience.
Requirements
5+ years of professional software development experience.
Strong experience with modern JavaScript/TypeScript ecosystems.
Experience with React, Next.js, Node.js, or similar technologies.
Solid understanding of system architecture, cloud infrastructure, databases, and API design.
Experience building scalable consumer-facing products.
Familiarity with blockchain technologies, Web3 infrastructure, wallets, smart contracts, or decentralized applications.
Strong knowledge of security best practices and application performance optimization.
Excellent problem-solving and communication skills.
Ability to work independently in a fast-paced startup environment.
Preferred Qualifications
Experience building Web3 or crypto products.
Understanding of decentralized identity, token ecosystems, or on-chain social applications.
Experience leading engineering teams or serving in a technical leadership role.
Background in DevOps, CI/CD, Docker, Kubernetes, or cloud platforms such as AWS or GCP.
Experience with real-time messaging, social platforms, or community products.
What We Offer
Competitive full-time compensation.
Opportunity to build a product from an early stage with significant technical ownership.
Flexible and remote-friendly work environment.
Collaborative team focused on innovation and long-term impact.
Work on cutting-edge Web3 technologies and help shape the future of digital communities.
Opportunity for career growth and leadership as the platform scales.
If you are excited about building the next generation of Web3 social experiences and want to make a meaningful impact from the earliest stages, we'd love to hear from you.
We are building a next-generation Web3 social platform designed to redefine how digital communities connect, collaborate, and grow.
Backed by years of experience within the cryptocurrency, blockchain, and digital asset ecosystem, our team has developed deep insights into how founders, developers, investors, creators, and communities interact. This understanding inspired us to create a platform that goes beyond financial applications and focuses on empowering meaningful social engagement.
Our mission is to build a transparent, community-driven social network where users can share ideas, collaborate on projects, discover opportunities, and create lasting relationships. We believe the next evolution of social media will be powered by decentralized technologies while maintaining an exceptional user experience, simplicity, and long-term sustainability.
We are seeking an experienced Chief Technology Officer (CTO) or Senior Full-Stack Developer who is passionate about Web3 and capable of leading the technical vision, architecture, and execution of our platform from the ground up.
Responsibilities
Lead the technical strategy and product architecture.
Design and build scalable backend systems and modern frontend applications.
Develop high-performance APIs and real-time features.
Integrate blockchain technologies, wallets, and Web3 authentication where appropriate.
Build secure, reliable, and maintainable infrastructure.
Collaborate closely with product, design, and leadership teams.
Establish engineering best practices, code quality standards, and development workflows.
Mentor engineers and help grow the technical organization.
Evaluate emerging technologies and implement solutions that improve scalability, security, and user experience.
Requirements
5+ years of professional software development experience.
Strong experience with modern JavaScript/TypeScript ecosystems.
Experience with React, Next.js, Node.js, or similar technologies.
Solid understanding of system architecture, cloud infrastructure, databases, and API design.
Experience building scalable consumer-facing products.
Familiarity with blockchain technologies, Web3 infrastructure, wallets, smart contracts, or decentralized applications.
Strong knowledge of security best practices and application performance optimization.
Excellent problem-solving and communication skills.
Ability to work independently in a fast-paced startup environment.
Preferred Qualifications
Experience building Web3 or crypto products.
Understanding of decentralized identity, token ecosystems, or on-chain social applications.
Experience leading engineering teams or serving in a technical leadership role.
Background in DevOps, CI/CD, Docker, Kubernetes, or cloud platforms such as AWS or GCP.
Experience with real-time messaging, social platforms, or community products.
What We Offer
Competitive full-time compensation.
Opportunity to build a product from an early stage with significant technical ownership.
Flexible and remote-friendly work environment.
Collaborative team focused on innovation and long-term impact.
Work on cutting-edge Web3 technologies and help shape the future of digital communities.
Opportunity for career growth and leadership as the platform scales.
If you are excited about building the next generation of Web3 social experiences and want to make a meaningful impact from the earliest stages, we'd love to hear from you.
Payment in Crypto
Tristika Criss
Backend Engineer with hands-on blockchain experience
Full time
Remote
We are building a modern hotel booking platform enhanced with Web3 capabilities, includingtoken-based payments, on-chain verification, and decentralized identity/ownership features.We’re looking for a Backend Engineer to design and build scalable backend systems andintegrate them with blockchain infrastructure. You’ll work closely with frontend and Web3engineers to deliver a seamless and reliable platform.
Payment in Crypto
Merklio
Senior Blockchain Engineer (Cosmos SDK & IBC)
Hong Kong
Hong Kong
Full time
Remote
Merklio is expanding its cross-chain orchestration layer. We are building a sovereign app-chain (Rollup-style) that aggregates liquidity from multiple L1s via IBC. We need a Blockchain Engineer to design, implement, and maintain our Cosmos-based chain.
Expectations:
Design custom modules (x/staking, x/rewards, x/merkl)
Implement IBC light clients and relayers
Optimize block time and state pruning
Write comprehensive unit & integration tests (Go test)
Build CLI tools for validators and delegators
Monitor node health and network upgrades
Collaborate with the research team on MEV-resistant ordering
Maintain chain upgrades (v1 → v2) with migration scripts
Write technical documentation for external validators
Nice to have:
Experience with Avalanche Subnets or Polkadot Substrate
Knowledge of HSM and key management
Open-source contributions to Cosmos SDK or related repos
Chinese+English language proficiency
Expectations:
Design custom modules (x/staking, x/rewards, x/merkl)
Implement IBC light clients and relayers
Optimize block time and state pruning
Write comprehensive unit & integration tests (Go test)
Build CLI tools for validators and delegators
Monitor node health and network upgrades
Collaborate with the research team on MEV-resistant ordering
Maintain chain upgrades (v1 → v2) with migration scripts
Write technical documentation for external validators
Nice to have:
Experience with Avalanche Subnets or Polkadot Substrate
Knowledge of HSM and key management
Open-source contributions to Cosmos SDK or related repos
Chinese+English language proficiency
Payment in Crypto
Milos Bogdanov
Senior Mobile application developer
Full time
Remote
I am looking for a developer who has much experience in Mobile application development.
But specially, candidate should be native in English.
Team communication is very important.
Please bid US only
Thank you
But specially, candidate should be native in English.
Team communication is very important.
Please bid US only
Thank you
Payment in Crypto
Christopher Clark
Web Developer
New York City, USA
New York City, USA
Full time
Remote
Hi,
I need a custom ebay like site for bitcoins or using stock credit on it. I need it to let you pay the user verbally, like an agreement you agree on that's it. I need the site fixed so it can be upgraded in the future.
I need it to be fixed so you can upload something to the site and sell it.
All I ask is keep the buying and selling part verbal agreements only. Like sending the user stock credit virtually.
Bid on things on the website
Sell things on the website
Buy things on the website
All I ask is keep the programming simple and the website in a simple form.
I need a website for the web browser and one for the phone web browsers.
If you can put in a custom user admin for it also, then that will be great.
Thank you,
Chris Clark (666 Encryption, CEO)
I need a custom ebay like site for bitcoins or using stock credit on it. I need it to let you pay the user verbally, like an agreement you agree on that's it. I need the site fixed so it can be upgraded in the future.
I need it to be fixed so you can upload something to the site and sell it.
All I ask is keep the buying and selling part verbal agreements only. Like sending the user stock credit virtually.
Bid on things on the website
Sell things on the website
Buy things on the website
All I ask is keep the programming simple and the website in a simple form.
I need a website for the web browser and one for the phone web browsers.
If you can put in a custom user admin for it also, then that will be great.
Thank you,
Chris Clark (666 Encryption, CEO)
Payment in Crypto