Serokell is a fast-growing, fully remote software development company that works on innovative solutions for complex problems. We’re packed full of adventurous, curious, and inclusive folks who want to build cutting-edge software with modern technologies like functional programming.

This position is open now with a July start. This is a project-based hire with the option to extend if it is a good match. Submit your CV and we’ll reach out promptly.

We’re seeking a middle to senior level Solidity Developer to join a team of fierce and fun Serokellers.

Hiring Process Overview: We invite candidates to the HR screening as the first step. Next, we conduct a technical interview with those whose profiles align with our requirements. Successful candidates will receive an offer.

Requirements:

• Fluency with Ethereum or another EVM-based blockchain ecosystem
• 2+ years in software development
• 1+ years experience writing, testing, and deploying Solidity contracts
• Hands-on experience with Hardhat, Foundry, Truffle, or Remix for development, testing, and debugging, including transaction submission, data retrieval, and key management
• Understanding of security issues and best practices for Ethereum and De-Fi applications
• Knowledge of popular token standards such as ERC-20, ERC-721, and ERC-1155
• Experience developing and integrating decentralized applications, both backend and frontend
• Basic understanding of cryptography primitives: public/private keys, signing, encryption, hashing
• Knowledge of fundamental algorithms and data structures like hash tables, binary search trees, DFS, quicksort
• Strong coding practices, including clean code structure, use of git, pull requests, and code review
• Fluent English, strong communication and collaboration skills
• Comfortable with daily stand-ups and asynchronous updates
• Self-driven, proactive, teamwork-oriented, curious and inclusive mindset
• Full-time commitment, around 140–160 hours per month
• Comfortable overlapping with team time zones from UTC 0 to UTC -8

It will be a significant plus if you have:

• Knowledge of TypeScript, Haskell, Rust, or OCaml
• Experience conducting security audits and identifying vulnerabilities
• Understanding of computer networks, HTTP, TCP/IP stack, and data synchronization models used in modern service APIs
• Familiarity with build/deploy automation tools and CI/CD systems such as Docker, Nix, Kubernetes

Responsibilities:

• Create and implement secure and efficient Solidity contracts, ensuring scalability, reliability, and maintainability
• Integrate contracts with EVM blockchain networks, often involving backend or frontend work
• Review and audit code
• Develop and execute unit tests, integration tests, and end-to-end tests
• Write detailed documentation for code, including design specs, user guides, and API documentation
• Stay updated on the latest developments in Solidity, Ethereum, and EVM-related technologies, cryptographic methods, and relevant programming languages
• Optimize code performance and gas efficiency
• Implement and enforce security best practices to protect contracts from common vulnerabilities
• Provide ongoing support and maintenance for deployed applications, addressing user-reported issues and bugs

We offer:

• Competitive salary.
• Engaging international projects.
• Participation in leading global conferences.
• International and multicultural teams.
• Fully remote work with flexible hours.
• Ability to take time off as needed.
• Investment in career and professional growth, with potential for wage increases.
• Mentoring and training programs.
• Opportunity to contribute to a leading functional programming blog.
• Therapy sessions for well-being support.

By joining Serokell, you’ll become part of a warm community of ingenious engineers, computer scientists, designers, marketing experts, and other inventive minds. You’ll work on ambitious projects building the next generation of computer software, explore creative initiatives unhindered by bureaucracy, and enjoy our vibrant Slack channels—ranging from #music to #philosophyandtears (did we mention the massive custom emoji set?).

Caiz

Revolutionizing Islamic Finance with Blockchain Technology

Are you ready to be part of a groundbreaking initiative that combines Islamic finance principles with cutting-edge blockchain technology?

Look no further than Caiz – The First Islamic Ecosystem Built on Blockchain

At Caiz, our mission is clear: to create a Fiqh compliant financial ecosystem that provides our community with fair and easy access to ethical financial products and services. We believe in empowering individuals to build a strong financial future while engaging in long-term economically beneficial behavior.

Our native coin, Caizcoin, that fuels the Caizblockchain. With Caizcoin, you can make seamless payments, store value, and interact with a range of ethical financial products we are developing. The centerpiece of our ecosystem is the innovative Caizapp, giving users complete control over their digital assets.

We are a passionate team reshaping finance, and we are expanding our dynamic workforce. Join us in a collaborative work environment focused on creating a fast and compliant money transfer structure.

Why to Join Caiz?

• Innovative & Purpose-Driven: At Caiz, we combine advanced blockchain technology with the principles of Islamic finance to create an innovative and modern financial system. Join us to be part of a forward-thinking organization that is reshaping the future of finance.
• Ethical Impact: As part of Caiz, you'll be working in an Organization that prioritizes ethics and integrity in all its operations, ensuring that every solution we offer aligns with the core values of fairness, transparency, and respect.
• Growth & Learning Opportunities: At Caiz, we value personal and professional growth. You'll have the opportunity to learn, innovate, and grow within a dynamic, supportive environment, while contributing to the development of ethical financial solutions.
• Global Vision, Local Impact: Caiz is focused on creating an inclusive, sustainable financial system that empowers individuals globally. You’ll be contributing to a company that has a positive impact on local communities and the global financial landscape.
• Collaborative Culture: We believe in teamwork and collaboration. You'll work alongside passionate professionals who are committed to driving change in the crypto and blockchain space, working together to create an ethical financial future.
• Secure & Transparent Environment: We emphasize trust and security in all aspects of our operations. As part of Caiz, you’ll be part of a transparent organization that values customer trust and ensures the highest security standards in the crypto space.

Tasks

We are looking for a highly skilled Blockchain Developer with expertise in Solidity and Rust to join our growing engineering team. You will play a key role in developing and optimizing smart contracts, blockchain protocols, and DeFi components that power the Caiz ecosystem.

As part of the core blockchain development team, you’ll work on both Ethereum-compatible smart contracts and Rust-based custom chain logic, contributing to secure, scalable, and innovative blockchain infrastructure.

Responsibilities:

• Design, develop, and deploy smart contracts using Solidity on EVM-compatible blockchains.
• Build and maintain Rust-based blockchain modules, such as on Substrate or Solana-compatible platforms.
• Contribute to the design of custom blockchain protocols and token standards.
• Write secure, gas-optimized, and thoroughly tested smart contracts.
• Collaborate with frontend and backend teams to integrate blockchain components into products.
• Conduct code reviews, audits, and vulnerability assessments for blockchain code.
• Analyze and improve the performance, security, and scalability of the Caiz blockchain.
• Stay up-to-date with the latest developments in blockchain technologies, including new EIPs, cryptographic primitives, and layer-2 solutions.

Requirements

Experience:

• 3+ years of experience in blockchain development with hands-on coding in Solidity and Rust.
• Strong understanding of smart contract design, blockchain architecture, cryptography, and consensus mechanisms.
• Experience developing and deploying smart contracts on Ethereum or similar EVM chains.
• Proficiency in Rust for blockchain environments such as Substrate or Solana.
• Familiarity with Web3.js, Ethers.js, Hardhat, Truffle, and related tools.
• Understanding of DeFi protocols, token standards (ERC-20, ERC-721, etc.), and layer-1/layer-2 ecosystems.
• Experience with version control systems (Git) and CI/CD workflows.
• Strong problem-solving skills and ability to write clean, maintainable code.

Preferred Skills

• Experience in building or contributing to a Layer 1 or Layer 2 blockchain.
• Knowledge of blockchain security best practices and audit processes.
• Exposure to zero-knowledge proofs (ZK), rollups, or cross-chain bridges.
• Experience in working within agile or startup environments.
• Understanding of Islamic finance or Sharia-compliant financial principles is a plus.

Level of studies: Bachelor’s degree in Computer Science, Software Engineering, Mathematics, or a related technical field.

Language Requirements: Fluent in English

Benefits

Benefits at Caiz:

• Competitive Financial Compensation: We offer financial benefits that reflect the value of your work and dedication.
• Work Flexibility: Enjoy the flexibility to work from home, the office, or even abroad.
• Annual Holidays: Generous paid time off to help you maintain a healthy work-life balance.
• Relocation Assistance: We provide relocation support for employees moving to new locations.
• Professional Development: Opportunities for training, certifications, and career growth.
• Employee Recognition: Programs to celebrate and reward your achievements and contributions.
• Inclusive & Collaborative Culture: A supportive and diverse work environment where your voice matters.
• Diversity, Equality, and Inclusion: We are committed to fostering a workplace that values diversity and promotes equality and inclusion for all employees.

Don't miss this opportunity – apply now and be part of the Caiz revolution.

Apply Now:

Location: Remote

🚀 About Technance

Technance is a crypto-native financial services company enabling secure access to digital asset infrastructure for institutions worldwide. From regulatory-grade custody to trading and compliance tools, we design and operate systems that bridge traditional finance and blockchain ecosystems.

We operate globally with a remote-first team, combining strategic expertise with technical rigor to build secure, scalable crypto infrastructure. If you’re passionate about blockchain architecture, DeFi protocols, and decentralized systems—join us to shape the core layer of institutional crypto adoption.

🔧 About the Role

We’re seeking a Senior Blockchain Developer to help design and implement smart contract systems, protocol integrations, and core blockchain infrastructure. You’ll work on a variety of systems ranging from token management frameworks and on-chain trading logic to custody and staking infrastructure.

This role is ideal for engineers who understand both the mechanics of blockchains and the requirements of secure financial systems.

✅ What You’ll Do

• Design and build smart contracts for Ethereum and EVM-compatible chains
• Integrate blockchain protocols into backend systems and trading platforms
• Contribute to the architecture and security of on-chain and off-chain interactions
• Build tooling for transaction automation, gas optimization, and risk controls
• Collaborate with backend, infrastructure, and security teams on system-wide designs
• Stay current on blockchain protocol updates, EIPs, L2s, and DeFi trends

📌 What We’re Looking For

• 4+ years of experience in software engineering, with 2+ years in blockchain development
• Strong experience in Solidity, smart contract development, and Ethereum toolchains (e.g., Hardhat, Foundry, Ethers.js)
• Deep understanding of EVM, gas efficiency, and contract security patterns
• Experience with backend systems using Go, TypeScript, or Python
• Familiarity with multisig wallets, oracles, bridges, staking mechanisms, and DeFi integrations
• Knowledge of blockchain-specific risks and ability to mitigate them through smart architecture
• Ability to thrive in a fully remote, async-first team culture

🎁 What We Offer

• 💸 Stable monthly payments in USDT
• 🌐 Fully remote role with global flexibility
• 🕒 Flexible work hours and async workflows
• 🔐 Work on high-impact, security-critical infrastructure
• 🧱 Be part of building the foundation for regulated institutional DeFi
• 🛠 Flat, engineering-led team with ownership over architecture and tooling
• 🚀 Opportunity to innovate in a fast-moving, blockchain-first environment

Apply Now:

As stewards of the Polkadot and Substrate ecosystem, Parity is laying the foundation for a better web. We believe in a decentralised web that respects the freedom and data of individuals and empowers developers to create better services. Our vision is to create a world based on truthful, rather than trustful, interactions.

Parity is one of the world's most experienced core blockchain infrastructure companies, having built and pioneered some of the most advanced technologies in the blockchain sector.

With a remote-first, global team, Parity is building open-source technologies for developers and organisations to implement and build upon. Our Web3 tech stack includes Polkadot, Substrate, and Kusama.

People in our collective are:

• Highly motivated to contribute to Parity’s mission and be part of something bigger

• Excited to work on projects that are groundbreaking and complex

• Autonomous workers that self-initiate, but also collaborate well with others

• Taking maximum accountability and having minimum ego at work

• Comfortable with chaos and adapting to the ever-changing Web3 space

• Continuously educating themselves about Parity and the wider ecosystem

About the team

The DevEx team works across the entire Polkadot ecosystem to improve developer workflows, tooling, and documentation. We own the experience of developers—from first contact with a template, guide, or CLI, to advanced tooling used in production.

This is not a support role. You’ll build the tools you wish already existed. You’ll collaborate with core engineering, marketing, solutions, and the community. You’ll also attend hackathons, support builders, and help scale what’s possible in the ecosystem.

About the Position

• Design and implement CLI tools, templates, SDKs, and onboarding flows.

• Improve and maintain documentation and developer portals.

• Write code samples, example projects, integration demos (Rust, TypeScript, Solidity).

• Contribute to better CI/CD setups for devs building with Substrate and Polkadot SDK.

• Engage with developer teams, answer deep technical questions, gather feedback.

• Work cross-functionally with engineering and product teams.

• Participate in events and hackathons, acting as an ambassador for great DevEx.

About You

• 3+ years of experience in Rust, 2+ years in TypeScript.

• Solidity experience — you’ve built and deployed smart contracts using Foundry, Hardhat, or Remix.

• Comfortable working with Linux, Docker, and CI/CD pipelines.

• A solid understanding of blockchain development, especially Substrate or EVM-based ecosystems.

• Experience writing technical documentation, tutorials, or guides.

• Confidence to speak with external developers — on Discord, Matrix, or in person.

• A bias toward automation, quality, and clarity.

• Enthusiasm for open source, hackathons, and building things developers love.

Bonus points for

• Experience with smart contracts.

• Contributions to open-source developer tools or frameworks.

• Involvement in blockchain communities, hackathons, or meetups.

About working for us

• Competitive remuneration packages based on iterative market research, including tokens (where legally possible)

• “Future of work” environment that’s remote-first and self-initiating with flexible hours

• Teammates that are genuinely excited about their impact and projects

• Access to the brightest minds in this space to learn about Web3 and develop your skills and knowledge while on the job

• Becoming part of the wider ecosystem (career and networking opportunities)

• Team and company-wide retreats

• Work laptop

• Opportunity to relocate to Germany or Portugal (with visa sponsorship)

Those joining our collective as an employee in Germany, Portugal, Switzerland and the U.K. also enjoy benefits such as health care, parental leave, PTO (28 days per year), local team events, yearly L&D budget, and language classes.

Parity is an Equal Opportunity Employer. We welcome diversity in our global team and care about everyone in our collective feeling included and welcome.

View our Applicant Notice to see how we use your data.

Is this position not quite your match? Browse our other open roles.

Apply Now:

As stewards of the Polkadot and Substrate ecosystem, Parity is laying the foundation for a better web. We believe in a decentralised web that respects the freedom and data of individuals and empowers developers to create better services. Our vision is to create a world based on truthful, rather than trustful, interactions.

Parity is one of the world's most experienced core blockchain infrastructure companies, having built and pioneered some of the most advanced technologies in the blockchain sector.

With a remote-first, global team, Parity is building open-source technologies for developers and organisations to implement and build upon. Our Web3 tech stack includes Polkadot, Substrate, and Kusama.

People in our collective are:

• Highly motivated to contribute to Parity’s mission and be part of something bigger

• Excited to work on projects that are groundbreaking and complex

• Autonomous workers that self-initiate, but also collaborate well with others

• Taking maximum accountability and having minimum ego at work

• Comfortable with chaos and adapting to the ever-changing Web3 space

• Continuously educating themselves about Parity and the wider ecosystem

About the team:

The DevEx team works across the entire Polkadot ecosystem to improve developer workflows, tooling, and documentation. We own the experience of developers—from first contact with a template, guide, or CLI, to advanced tooling used in production.

This is not a support role. You’ll build the tools you wish already existed. You’ll collaborate with core engineering, marketing, solutions, and the community. You’ll also attend hackathons, support builders, and help scale what’s possible in the ecosystem.

About the Position

We're looking for a Developer Experience Manager to lead and scale the efforts that make building on our ecosystem delightful for developers. This role is part player, part coach, balancing hands-on contributions with strategic direction, internal coordination, and developer advocacy. You’ll work closely with engineering, product, and leadership to improve tooling, documentation, and support for teams building with Substrate and the Polkadot SDK.

• Own and evolve our DevEx strategy across SDKs, CLIs, onboarding, and developer tooling.

• Prioritize and drive improvements to documentation, developer portals, and support flows.

• Collaborate with internal teams to identify pain points and streamline dev workflows.

• Represent developer needs in roadmap discussions and influence cross-functional planning.

• Guide technical writers, engineers, and advocates to produce high-quality samples, demos, and content.

• Lead feedback loops with internal and external developers to continuously improve the experience.

• Participate in community events and champion best practices for developer success.

About You

• 8+ years of experience in software engineering, including 2+ years in developer tooling or DevEx roles.

• Proficient in Rust and TypeScript, with a strong understanding of the smart contract landscape (e.g., Solidity + Foundry/Hardhat).

• Strong communicator and collaborator; experienced in working across product, engineering, and leadership teams.

• Comfortable running internal discovery efforts and aligning technical direction with business goals.

• Deep understanding of developer workflows  from onboarding to CI/CD to debugging.

• Experienced in writing and reviewing documentation, tutorials, or onboarding flows.

• Passion for supporting developers, both internally and externally.

Bonus points for

• Experience managing or mentoring DevEx or DevRel teams.

• Contributions to open-source developer tools or frameworks.

• Participation in hackathons, community programs, or educational initiatives.

About working for us

• Competitive remuneration packages based on iterative market research, including tokens (where legally possible)

• “Future of work” environment that’s remote-first and self-initiating with flexible hours

• Teammates that are genuinely excited about their impact and projects

• Access to the brightest minds in this space to learn about Web3 and develop your skills and knowledge while on the job

• Becoming part of the wider ecosystem (career and networking opportunities)

• Team and company-wide retreats

• Work laptop

• Opportunity to relocate to Germany or Portugal (with visa sponsorship)

Those joining our collective as an employee in Germany, Portugal, Switzerland and the U.K. also enjoy benefits such as health care, parental leave, PTO (28 days per year), local team events, yearly L&D budget, and language classes.

Parity is an Equal Opportunity Employer. We welcome diversity in our global team and care about everyone in our collective feeling included and welcome.

View our Applicant Notice to see how we use your data.

Is this position not quite your match? Browse our other open roles.

Apply Now: