Senior Backend Engineer (f/m)
Status
Paris, France
Full time
Hybrid
Compensation is not specified
Role
Backend Engineer
Description
We are dedicated to making digital assets accessible and secure for everyone. Join us in our mission.
Firmly established in 2014, we are a worldwide platform for digital assets and Web3. Our Ledger Nanos are responsible for securing over 20% of the world's crypto assets. With our headquarters in Paris and Vierzon, alongside offices in various countries, we have a team of over 700 professionals crafting diverse products and services. This enables individuals and businesses to safely buy, store, exchange, increase, and manage crypto assets. Our Ledger hardware wallets line has already sold over 6 million units in 200 countries.
Our core values at Ledger are Pragmatism, Audacity, Commitment, Trust, and Transparency. Take a look at our Origins video for more insight.
We are seeking a Backend Engineer to be responsible for developing a backend application that facilitates financial institutions in processing transactions within the cryptocurrency space.
The Ledger Vault provides a SaaS solution catering to protecting large and diverse amounts of cryptocurrencies while decreasing risks from IT and physical threats. This high-security enterprise solution leverages "HSM" (Hardware Security Module) and hardware authenticators. It offers a turnkey SaaS hardware/software suite that can manage multiple cryptocurrencies with advanced governance policies, including multi-authorization, rate-limiting, and time-locking.
We are looking for talented individuals to construct a stable and scalable platform for the BtoB financial market.
Your Role:
- Design and establish our governance and orchestration layer, along with a series of complex APIs
- Interact with cryptographic modules (HSM) and blockchain interfaces
- Integrate new cryptocurrencies on Vault
- Collaborate with the Product team to comprehend end-user requirements and convert them into realistic technical solutions
- Engage in a cross-team environment, interfacing with Vault’s Frontend and QA engineers, as well as cross-functional teams like Core, Firmware, Infrastructure, and Operations
- Participate in troubleshooting sessions and engage with stakeholders such as Technical Account Managers
Requirements:
- Minimum of 5 years experience in a Backend (Node.JS) / Software Engineering role, ideally in a product-based startup environment
- At least 3 years of experience in TypeScript as the primary language
- Capacity for self-learning in backend languages like Python and RUST
- Familiarity with software development best practices including version control, code reviews, testing, and CI/CD
- Proficient in agile methodologies (Scrum/XP/Kanban)
- Experienced in multicultural environments with English proficiency
Preferred Qualifications:
- Some experience with Python (Flask, FastAPI)
- Proficient in RESTful API design and standards
- Interest in other API frameworks (e.g. GraphQL) and involvement in message-based systems
- Willingness to expand skills across various product components
- Interest in cryptocurrencies and blockchain technology
- Active participation in the open-source community, such as speaking at conferences, attending meetups, writing blogs, contributing code, etc.
Benefits:
- Stock options to share in the company’s success
- Hybrid work policy for greater flexibility
- Enjoy social events, snacks, and drinks, with an annual company outing
- Comprehensive health insurance coverage
- Personal development opportunities, coaching, and fitness resources
- Five weeks of paid leave per year, in addition to national holidays and RTT days
- Access to high-performance office equipment and gadgets
- Reimbursement for transportation costs
- Employee discount on company products
We are a diverse and inclusive employer promoting equality for all individuals regardless of gender, ethnicity, religion, sexual orientation, social status, disability, or age.
Skills Required
Ledger
Website
www.ledger.comCompany size
Not specified
Location
United States
Description
Not specified
Status
onyesi kosisochukwu
Marketing manager
Witney, UK
Witney, UK
Full time
Hybrid
We are seeking a highly motivated and experienced Marketing Manager to join our team. The primary responsibilities of this role will include developing and implementing marketing strategies to drive brand awareness, lead generation, and customer engagement. This individual will be responsible for overseeing all aspects of marketing, including online and offline campaigns, social media, email marketing, SEO, and more.
Required Skills:
- Proficiency in Web, Mobile & Software Development
- Strong understanding of Design & Creative principles
- Knowledge of Legal, Accounting and Consulting practices
- Familiarity with Blockchain & Cryptocurrency trends
- Understanding of NFT (Non-Fungible Token) market
- Ability to collaborate with Engineering & Architecture teams
The ideal candidate will have a proven track record of successfully leading marketing initiatives in a fast-paced environment. Strong communication skills, attention to detail, and a creative mindset are essential for this role. If you are passionate about marketing and have a diverse skill set across various industries, we would love to hear from you.
Join our team and be a part of our innovative and dynamic company as we continue to grow and expand our reach in the market. Apply now and take the next step in your marketing career!
Required Skills:
- Proficiency in Web, Mobile & Software Development
- Strong understanding of Design & Creative principles
- Knowledge of Legal, Accounting and Consulting practices
- Familiarity with Blockchain & Cryptocurrency trends
- Understanding of NFT (Non-Fungible Token) market
- Ability to collaborate with Engineering & Architecture teams
The ideal candidate will have a proven track record of successfully leading marketing initiatives in a fast-paced environment. Strong communication skills, attention to detail, and a creative mindset are essential for this role. If you are passionate about marketing and have a diverse skill set across various industries, we would love to hear from you.
Join our team and be a part of our innovative and dynamic company as we continue to grow and expand our reach in the market. Apply now and take the next step in your marketing career!
Payment in Crypto
Astra Byte Sync
Blockchain Specialist for Game-Fi Project
Full time
Remote
We are seeking a skilled Blockchain Specialist to become a part of our groundbreaking Game-Fi initiative! If you have a deep passion for gaming, decentralized finance, and the latest technological advancements, this could be your ideal role.
Primary Duties:
- Create and implement smart contracts for in-game transactions and assets.
- Develop secure blockchain solutions that guarantee player ownership and protect asset integrity.
- Work closely with our game development team to smoothly incorporate blockchain technology into our gaming platform.
- Keep abreast of the latest developments and best practices within the blockchain and gaming sectors.
Qualifications:
- Demonstrated experience as a Blockchain Developer or in a similar position.
- Expertise in Solidity, with experience in Ethereum or other blockchain technologies.
- Solid understanding of Game-Fi principles and how blockchain can elevate the gaming experience.
- Familiarity with DeFi protocols and tokenomics.
- Ability to work effectively within a team and convey technical information to non-technical audiences.
Desirable Skills:
- Experience in NFT development and related platforms.
- Understanding of cryptographic concepts and security best practices.
If you are eager to embrace a new challenge and contribute to the evolution of gaming through blockchain technology, we would love to hear from you!
Primary Duties:
- Create and implement smart contracts for in-game transactions and assets.
- Develop secure blockchain solutions that guarantee player ownership and protect asset integrity.
- Work closely with our game development team to smoothly incorporate blockchain technology into our gaming platform.
- Keep abreast of the latest developments and best practices within the blockchain and gaming sectors.
Qualifications:
- Demonstrated experience as a Blockchain Developer or in a similar position.
- Expertise in Solidity, with experience in Ethereum or other blockchain technologies.
- Solid understanding of Game-Fi principles and how blockchain can elevate the gaming experience.
- Familiarity with DeFi protocols and tokenomics.
- Ability to work effectively within a team and convey technical information to non-technical audiences.
Desirable Skills:
- Experience in NFT development and related platforms.
- Understanding of cryptographic concepts and security best practices.
If you are eager to embrace a new challenge and contribute to the evolution of gaming through blockchain technology, we would love to hear from you!
Payment in Crypto
Winnables
Full Stack Developer (Front End Leaning)
Full time
Remote
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.
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.
berttha walker
UI/UX Designer
Full time
Remote
UI/UX Designer for SaaS Dashboard (Figma)
Job Summary:
We're building ClearTrack, a lightweight SaaS tool for tracking tasks and performance in remote teams. We're looking for a UI/UX designer to design 6–8 clean, modern dashboard screens (desktop + mobile).
Scope of Work:
1. Design dashboard UI (Task List, Time Tracker, Reports, Settings)
2. Create responsive mockups in Figma
3. Deliver clickable prototype + style guide
4. Collaborate with our developer for smooth handoff
Budget:
Fixed: $800–$1200 (negotiable based on experience)
Requirements:
1. SaaS/dashboard UI design experience
2. Proficiency in Figma
3. Strong communication & fast turnaround
To Apply:
If you're interested, please:
1. Send a short proposal letter explaining why you're a good fit
2. Share your portfolio (SaaS/dashboard preferred)
3. Include your email address
4. Mention your availability and estimated delivery time
Bonus if you have:
Experience designing admin panels or productivity tools
Job Summary:
We're building ClearTrack, a lightweight SaaS tool for tracking tasks and performance in remote teams. We're looking for a UI/UX designer to design 6–8 clean, modern dashboard screens (desktop + mobile).
Scope of Work:
1. Design dashboard UI (Task List, Time Tracker, Reports, Settings)
2. Create responsive mockups in Figma
3. Deliver clickable prototype + style guide
4. Collaborate with our developer for smooth handoff
Budget:
Fixed: $800–$1200 (negotiable based on experience)
Requirements:
1. SaaS/dashboard UI design experience
2. Proficiency in Figma
3. Strong communication & fast turnaround
To Apply:
If you're interested, please:
1. Send a short proposal letter explaining why you're a good fit
2. Share your portfolio (SaaS/dashboard preferred)
3. Include your email address
4. Mention your availability and estimated delivery time
Bonus if you have:
Experience designing admin panels or productivity tools
Payment in Crypto
AXERAT
Back End Developer in AI projects
Singapore
Singapore
Full time
Remote
We are seeking a skilled and proactive AI Integrator to join our team and lead the integration of artificial intelligence technologies into our business operations, products, and services. This role is pivotal in bridging the gap between data science, engineering, and business units, ensuring the seamless deployment, scaling, and optimization of AI-driven solutions.
You will work closely with stakeholders across product, engineering, data science, and operations to identify opportunities for AI integration, manage implementation, and maintain AI systems post-deployment.
Key Responsibilities:
Collaborate with cross-functional teams to identify and prioritize opportunities for AI integration.
Evaluate and select appropriate AI/ML tools, APIs, and frameworks that align with business objectives.
Deploy and integrate AI models into production environments and existing systems (e.g., CRM, ERP, customer support platforms).
Develop automation workflows using AI tools (e.g., ChatGPT, Claude, Azure AI, Google Vertex AI).
Ensure data pipelines, model outputs, and integrations are reliable, secure, and scalable.
Translate business needs into technical requirements for AI systems.
Monitor, troubleshoot, and optimize deployed AI systems for accuracy, performance, and ethical alignment.
Maintain documentation and provide training or support to internal teams on AI tools and capabilities.
Stay current with AI trends, emerging technologies, and best practices.
Required Qualifications:
Certified specialist in AI or Bachelors or Masters degree in Computer Science, Engineering, Data Science, or a related field.
Familiarity with cloud platforms (AWS, GCP, Azure) and their AI services.
Strong understanding of APIs, microservices architecture, and RESTful integration.
Excellent communication skills and ability to translate complex AI concepts for non-technical stakeholders.
Preferred Qualifications:
Experience with GenAI tools like OpenAI (GPT-4), Anthropic Claude, or Google Gemini.
Knowledge of prompt engineering and small language model (SLM) orchestration.
Experience integrating AI into SaaS or enterprise software products.
Background in data security, compliance, and AI ethics.
You will work closely with stakeholders across product, engineering, data science, and operations to identify opportunities for AI integration, manage implementation, and maintain AI systems post-deployment.
Key Responsibilities:
Collaborate with cross-functional teams to identify and prioritize opportunities for AI integration.
Evaluate and select appropriate AI/ML tools, APIs, and frameworks that align with business objectives.
Deploy and integrate AI models into production environments and existing systems (e.g., CRM, ERP, customer support platforms).
Develop automation workflows using AI tools (e.g., ChatGPT, Claude, Azure AI, Google Vertex AI).
Ensure data pipelines, model outputs, and integrations are reliable, secure, and scalable.
Translate business needs into technical requirements for AI systems.
Monitor, troubleshoot, and optimize deployed AI systems for accuracy, performance, and ethical alignment.
Maintain documentation and provide training or support to internal teams on AI tools and capabilities.
Stay current with AI trends, emerging technologies, and best practices.
Required Qualifications:
Certified specialist in AI or Bachelors or Masters degree in Computer Science, Engineering, Data Science, or a related field.
Familiarity with cloud platforms (AWS, GCP, Azure) and their AI services.
Strong understanding of APIs, microservices architecture, and RESTful integration.
Excellent communication skills and ability to translate complex AI concepts for non-technical stakeholders.
Preferred Qualifications:
Experience with GenAI tools like OpenAI (GPT-4), Anthropic Claude, or Google Gemini.
Knowledge of prompt engineering and small language model (SLM) orchestration.
Experience integrating AI into SaaS or enterprise software products.
Background in data security, compliance, and AI ethics.
Payment in Crypto