Lead / Senior Software Developer - Mainapp Platform Team

At Relai, we are on a mission to make Bitcoin the go-to savings technology—simple, accessible, and secure. As Europe’s leading Bitcoin startup, we’re pioneering the future of Bitcoin investing by making it effortless for individuals and institutions alike to buy, sell, and hold Bitcoin without complexity or middlemen. With $12M in Series A funding and rapid growth, we are expanding our team of passionate Bitcoiners.
We’re looking for a Senior Go Developer (m/f/d) to play a pivotal role in enhancing Relai’s mobile experience, ensuring high-net-worth individuals (HNWIs) and small-medium-sized businesses (SMEs) have a seamless and secure way to grow their Bitcoin holdings. Your contributions will directly impact our ability to deliver an intuitive, world-class app for Bitcoin investing.
Your Role
As a Senior Go developer, you will:
Design, develop, and maintain high-quality backend microservices using Go, ensuring scalability, reliability, and performance.
Collaborate closely with cross-functional teams, including product managers, DevOps engineers, and QA/test engineers, to deliver robust and well-tested solutions.
Participate in code reviews and audits, providing constructive feedback to maintain high standards of code quality and best practices.
Optimize application performance, ensuring efficient use of resources and minimal latency in production systems.
Contribute to architecture decisions, participating in the design of distributed systems and ensuring the system's modularity and maintainability.
Implement and maintain APIs, ensuring seamless communication between services and external systems.
Troubleshoot and resolve issues, debugging production-level problems quickly and effectively.
Stay up to date with Go best practices, new tools, and industry trends, and share knowledge with the team.
 
What You Bring
5+ years of professional experience in a similar backend development role, with a strong focus on building scalable systems.
3+ years of hands-on experience with Go (Golang), demonstrating proficiency in writing clean, efficient, and maintainable code.
A strong preference for simple, iterative solutions, with a commitment to continuous improvement and optimization.
An obsession with maintainable, high-quality code, adhering to best practices and ensuring long-term sustainability.
A self-starter mindset, capable of working independently and delivering results with minimal supervision.
Proven experience in API development, including designing and maintaining RESTful or gRPC interfaces.
Familiarity with CI/CD pipelines and tools to streamline development and deployment workflows.
Experience working in an agile environment, embracing collaboration, feedback, and iterative progress.
Solid knowledge of cloud and microservice design patterns, with an understanding of distributed systems architecture.
Why Join Relai?
100% remote work – Join a fully remote, flexible team working across Europe.
Relai provides you with the latest MacBook laptop and an iPhone to ensure smooth and effective work.
Competitive salary + employee participation – We grow together.
0% fees on Bitcoin purchases at Relai – stack sats effortlessly.
Meaningful perks – Blinkist, Spotify, and Netflix subscriptions on us.
A senior role in a fast-growing Bitcoin company – Make a real impact in shaping the future of Bitcoin adoption in Europe.

About us
Bitget is one of the world's leading digital assets ecosystems. With over 120 million registered users, Bitget has one of the most comprehensive suites of blockchain products and services available.
Our mission is to support the growth of the digital assets industry and we believe it represents the future of finance. What we do empowers the future of finance by ensuring secure, efficient and smart digital transactions.
We are one of the fastest growing companies in the digital asset sector. If you are looking for cutting-edge work, where you will have opportunities to develop your career among peers who are experts in their field, and you believe in the future of digital currency, then look no further than Bitget!
 
What you'll do
 
User Experience Optimization: Identify pain points and opportunities in P2P transaction processes to enhance user experience.
Risk Management: Implement and oversee fraud prevention strategies to ensure compliance with regulatory and internal requirements.
Data Analysis: Track and analyze key performance indicators KPI to pinpoint issues. - Collaboration: Partner with product, marketing, and technical teams to drive the launch of new features and ensure the platform evolves to meet market demands.
User Support: Maintain communication with the customer service team to establish SOPs for issue resolution and reduce customer complaint rates.
 
What you'll need
 
At least 2+ years of P2P operations experience; ideally with experience in cryptocurrency or fintech sectors.
Strong analytical thinking skills, with the ability to interpret data and make data-driven decisions.
Excellent communication and problem-solving abilities.
Exceptional verbal and written communication skills (proficient in both Mandarin and English).
 
Why Bitget?
 
Bitget is the world's leading web 3 platform for copy trading and one of the world's largest and most respected exchanges
We are a global company with staff members from over 50 different countries and regions
We are growing and looking for world-class ambitious talents to help us continue this journey
We have a streamlined structure that empowers employees to work efficiently, delivering the best results in a short timeframe
We offer competitive salaries and benefits
Blockchain technology and digital assets have the potential to change finance in a way no other technology can - be part of it!
 

About the Role
We are looking for a Senior Blockchain Developer to join our team and lead the design, development, and deployment of cutting-edge decentralized applications and smart contracts. You will play a pivotal role in shaping our Web3 architecture, ensuring scalability, security, and performance across our ecosystem.
Responsibilities
Design, develop, and deploy smart contracts and blockchain-based applications.
Architect scalable, secure, and reliable blockchain infrastructure.
Lead code reviews, mentor junior developers, and set technical best practices.
Collaborate with product, design, and business teams to translate requirements into technical solutions.
Stay ahead of emerging blockchain trends (L2s, interoperability, zero-knowledge proofs, token standards).
Integrate blockchain solutions with existing APIs, databases, and backend services.
Ensure security audits, gas optimization, and compliance with industry standards.

At Tenderly, we're not just shaping the future of blockchain technology – we're defining it. As a full-stack Web3 infrastructure platform, we provide multi-network support and a comprehensive ecosystem that covers every aspect of the blockchain journey, from initial encounters to advanced Node solutions and serverless cloud compute functions.Our mission is crystal clear: to empower developers worldwide to harness the full potential of blockchain technology for creating innovative products. With our robust Web3 infrastructure platform, we've already enabled tens of thousands of developers to work more efficiently with blockchain. We thrive on tackling complex challenges head-on, crafting solutions that push the boundaries of what's possible in the blockchain world. From developing bespoke Ethereum Virtual Machine (EVM) implementations to designing proprietary storage layers optimized for our advanced blockchain node solutions, our team is at the forefront of industry innovation. About the RoleAre you ready to revolutionize the user experience in blockchain technology? As a Frontend Engineer at Tenderly, you will play a key role in shaping our platform’s user experience while ensuring the highest standards of quality and performance. Your role will be pivotal in driving excellence in our frontend development. What you’ll do✦ Develop and Maintain: Create and sustain frontend components and features using JavaScript, TypeScript, and React.✦ Collaborate: Work closely with across engineering and product teams to align technical solutions with company objectives, ensuring seamless integration of design and functionality.✦ Architect: Contribute to architectural decisions that drive scalability, performance, and alignment with business priorities, keeping us at the forefront of Web3 innovation.✦ Contribute: Provide technical expertise and support testing and validation efforts to ensure the success of our platform. Our Technology StackAt Tenderly, we leverage a sophisticated technology stack to deliver cutting-edge solutions. As a Frontend Engineer, you’ll work extensively with:- JavaScript- TypeScript- React- Golang (for full-stack collaboration)- Google Cloud Platform- Amazon Web Services- Supporting technologies including PostgreSQL, Kafka, Cassandra, and more About YouWe’re looking for a highly skilled and innovative frontend developer with a passion for creating exceptional user experiences. You should have:✦ Proven Experience: Demonstrated experience in technical roles, showcasing your ability to deliver high-quality software products.✦ Technical Expertise: Mastery of JavaScript, TypeScript, and React, with a deep understanding of modern frontend development practices and tools.✦ Architectural Vision: Strong decision-making skills to drive scalability, extensibility, and performance in our platform.✦ Effective Communication: Excellent communication and teamwork abilities, ensuring effective collaboration and transparent communication channels.What we offerWhy Tenderly?Join us at Tenderly, where our values are not just words on a page but the driving force behind our innovative journey.Fanatic DriveWe're passionately driven to solve our users' problems, tackling challenges with intensity and speed. Our work is our obsession, and we thrive on the fast-paced world of Web3.Underdog MentalityWe love defying the odds, rejecting the status quo, and achieving the impossible. We're on a mission to revolutionize blockchain technology, constantly pushing boundaries.Inward ResponsibilityWe hold ourselves accountable, always striving to improve. We embrace feedback, knowing it drives personal growth and collective success.Intentional CollaborationOur success relies on individual contributions and mutual support. We share ideas openly, trust each other completely, and continuously push each other to excel.Tenderly Transparency™️We believe in open, honest communication. We share knowledge and opinions freely, fostering a culture of accountability and trust.Tenderly is committed to creating a diverse environment and is proud to be an equal-opportunity employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, gender, gender identity or expression, sexual orientation, national origin, genetics, disability, age, or veteran status. To find out more: https://tenderly.co/careers

Job Description:
Winnables.com is looking for a creative front-end-leaning Full Stack Developer who loves bringing slick, engaging user experiences to life while still caring about the behind-the-scenes details.
You’ll collaborate closely with designers and product leads, iterate quickly on new ideas, and see the direct impact of your work in the hands of players around the world.
If you enjoy mixing imaginative front-end polish with just enough back-end know-how to make the magic happen, we’d love to hear from you.
Key Responsabilities:
Transform design mock-ups and product concepts into polished, responsive game screens, animations, and flows.
Collaborate daily with designers, product leads, and blockchain engineers to prototype, ship, and iterate on new games or new features.
Continuously test, debug, and optimize for performance across devices and network conditions.
Review code, share best practices, and help keep our small codebase clean, secure, and easy to extend.
Use player feedback and analytics to refine existing features and guide new ideas from concept to launch.
Champion accessibility and web-standards compliance, ensuring every player—regardless of device or ability—has a first-class experience.
What You’ll Be Building
Build interactive mini-games that deliver smooth, responsive gameplay.
Create real-time multiplayer features and live game mechanics.
Develop pack-opening systems with eye-catching, engaging animations.
Engineer raffle and lottery-style games that are fully on-chain and provably fair.
Implement Plinko and other physics-based games, tuned for fun and balance.
Craft user-friendly interfaces that perform flawlessly across mobile, tablet, and desktop.
Qualifications:
Tech Stack:
Core: TypeScript · React & Next.js · Node.js · Zustand · WebSockets & REST
Data & Infra: PostgreSQL (Supabase) · Redis · Docker · GitHub
Observability: Grafana · PostHog
Design & Web3: Figma · viem / wagmi
What We're Looking For
Strong experience with TypeScript and modern JavaScript
Solid understanding of React and Next.js ecosystem
Experience building real-time applications with WebSockets
Familiarity with Node.js backend development
Knowledge of PostgreSQL and database design
Experience with responsive design and mobile-first development
Understanding of state management patterns (Zustand experience preferred)
Understanding of web security fundamentals (CSRF protection, secure authentication flows, input validation)
Interest in gaming mechanics and interactive user experience.
Nice to Have
Experience with gaming or interactive application development
Knowledge of blockchain technologies and Web3 integration
Familiarity with monitoring tools (Grafana, PostHog)
Experience with Docker and containerization
Understanding of real-time multiplayer game architecture
 
Company Description:
Winnables.com is on a mission to re-imagine iGaming through full on-chain transparency. We believe players deserve provably fair odds, transparent math, and no black-box RNGs. Every spin and ticket purchase is recorded immutably on Ethereum, so anyone can audit the outcome, track prize pools, or even build their own analytics on top of our contracts.
All of our games are designed and engineered 100% in-house by a small, senior team that blends game design, cryptography, and smart-contract security. We currently operate two flagship experiences:
Raffles – transparent prize drawings where every ticket lives on-chain, letting players verify fairness before and after the draw.
Loot Packs – blockchain-powered loot boxes that reveal randomized rewards with engaging pack-opening animations.
We’re still just getting started. The roadmap is full of green-field challenges—and real, measurable impact on an industry ripe for change. Join us and help craft the next generation of fair, fun, and truly player-owned gaming.