Senior Backend Engineer (f/m)
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
Ledger is a leader in security and infrastructure solutions for cryptocurrencies and blockchain applications. We are constantly looking for innovative, talented people to join our team.
Iron Key Capital
Founder Fellow
Full time
Remote
Founder Fellow
📍 Remote | 3-Month Contract
🚀 About Iron Key & Iron Key Capital
Iron Key, backed by Iron Key Capital, is a venture community and investment firm focused on liquid and venture opportunities in crypto, Web3, and AI. Our mission is to invest in and support Pre-Seed and Seed-stage startups, equipping founders and investors with the tools and knowledge they need to succeed.
We operate a blockchain innovation lab and incubate startups in venture infrastructure, fintech, IP ownership, and application development. Iron Key Capital is backed by 200+ global LPs, deploying $1M+ annually into emerging opportunities.
📢 The Opportunity: Entrepreneur in Residence (EIR)
We are seeking a technical co-founder or EIR to help bring a newly incubated venture infrastructure product to market. This is a 3-month remote contract role, ideal for builders with Web3 and AI experience who want to launch a company with hands-on support.
Iron Key has developed proprietary AI tools for internal workflows and is exploring opportunities to externalize these as software-based consulting services or standalone software products. As an EIR, you’ll play a critical role in shaping, launching, and scaling these innovations.
🔹 Key Responsibilities
Lead Startup Development – Take an incubated idea from concept to market launch.
Drive Innovation – Bring your own venture idea or work on an existing Iron Key product.
Strategic Execution – Develop and implement growth strategies.
Hands-on AI & Web3 Work – Build and iterate on cutting-edge solutions in AI and blockchain.
Leverage Resources – Work alongside investors, advisors, and a global network to accelerate your startup.
🎯 What We’re Looking For
Proven entrepreneurial experience – Ideally, you’ve built a startup before (even if it failed).
Deep Web3 or AI expertise – Hands-on experience in AI, blockchain, or fintech is a must.
Strong problem-solving mindset – Ability to pivot, adapt, and execute in fast-changing environments.
Leadership & Vision – You’re a self-starter who can drive a business forward.
🔥 Why Join Iron Key?
Founder-Centric Program – Hands-on support to launch a company.
Unmatched Network – Access to top investors, mentors, and builders in crypto and AI.
Long-Term Value – Lifetime membership in the Iron Key community & alumni network.
Fundraising Support – Get exposure to global investors and funding opportunities.
📩 Apply Now
If you're ready to build and scale a new venture, apply here:
👉 https://airtable.com/appfCDlkorF5FL3VZ/paggWhwbIDwnmlzlK/form
📍 Remote | 3-Month Contract
🚀 About Iron Key & Iron Key Capital
Iron Key, backed by Iron Key Capital, is a venture community and investment firm focused on liquid and venture opportunities in crypto, Web3, and AI. Our mission is to invest in and support Pre-Seed and Seed-stage startups, equipping founders and investors with the tools and knowledge they need to succeed.
We operate a blockchain innovation lab and incubate startups in venture infrastructure, fintech, IP ownership, and application development. Iron Key Capital is backed by 200+ global LPs, deploying $1M+ annually into emerging opportunities.
📢 The Opportunity: Entrepreneur in Residence (EIR)
We are seeking a technical co-founder or EIR to help bring a newly incubated venture infrastructure product to market. This is a 3-month remote contract role, ideal for builders with Web3 and AI experience who want to launch a company with hands-on support.
Iron Key has developed proprietary AI tools for internal workflows and is exploring opportunities to externalize these as software-based consulting services or standalone software products. As an EIR, you’ll play a critical role in shaping, launching, and scaling these innovations.
🔹 Key Responsibilities
Lead Startup Development – Take an incubated idea from concept to market launch.
Drive Innovation – Bring your own venture idea or work on an existing Iron Key product.
Strategic Execution – Develop and implement growth strategies.
Hands-on AI & Web3 Work – Build and iterate on cutting-edge solutions in AI and blockchain.
Leverage Resources – Work alongside investors, advisors, and a global network to accelerate your startup.
🎯 What We’re Looking For
Proven entrepreneurial experience – Ideally, you’ve built a startup before (even if it failed).
Deep Web3 or AI expertise – Hands-on experience in AI, blockchain, or fintech is a must.
Strong problem-solving mindset – Ability to pivot, adapt, and execute in fast-changing environments.
Leadership & Vision – You’re a self-starter who can drive a business forward.
🔥 Why Join Iron Key?
Founder-Centric Program – Hands-on support to launch a company.
Unmatched Network – Access to top investors, mentors, and builders in crypto and AI.
Long-Term Value – Lifetime membership in the Iron Key community & alumni network.
Fundraising Support – Get exposure to global investors and funding opportunities.
📩 Apply Now
If you're ready to build and scale a new venture, apply here:
👉 https://airtable.com/appfCDlkorF5FL3VZ/paggWhwbIDwnmlzlK/form
Utopos
Job Opportunity: AI Engineer for UFO Image/video Authentication System 👽
Full time
Remote
🚀 Job Opportunity: AI Engineer for UFO Image Authentication System 👽
About Us:
We are building a cutting-edge AI-powered system to analyze and authenticate UFO images using machine learning, computer vision, and blockchain verification. Our goal is to separate fact from fiction and create a decentralized, transparent UFO sighting database. We are looking for a talented AI Engineer to help develop this groundbreaking system.
Role: AI Engineer (Computer Vision & Machine Learning)
Location: Remote
Contract Type: Freelance / Full-time
Responsibilities:
🔹 Develop and train deep learning models (CNNs, GANs) to detect manipulated, AI-generated, or authentic UFO images.
🔹 Build a real-time image analysis system capable of categorizing UFO sightings.
🔹 Implement object recognition & anomaly detection to classify spacecraft, weather phenomena, and aircraft.
🔹 Integrate blockchain & decentralized storage (IPFS) for verified image records.
🔹 Develop a user submission & verification portal that allows experts to weigh in on authenticity.
Requirements:
✅ Strong experience in TensorFlow, PyTorch, or OpenCV for image recognition.
✅ Experience with YOLO or other object detection models.
✅ Knowledge of deepfake detection and GAN analysis.
✅ Experience with blockchain for data integrity (Polygon, Ethereum, or Hyperledger).
✅ Ability to process large-scale datasets from online sources & government archives.
Bonus Skills:
⭐ Background in astronomy, aerospace, or remote sensing.
⭐ Experience working with NASA, FAA, MUFON, or other UFO databases.
⭐ Previous work in forensic image analysis & metadata authentication.
Why Join Us?
🚀 Be part of a pioneering AI research project to uncover real UFO sightings.
🔍 Work with leading experts in AI, aerospace, and blockchain.
💰 Competitive pay in crypto, UTOP.
📩 Apply Now! Send your portfolio, GitHub, and resume. Let’s reveal the truth together! 👽📡
About Us:
We are building a cutting-edge AI-powered system to analyze and authenticate UFO images using machine learning, computer vision, and blockchain verification. Our goal is to separate fact from fiction and create a decentralized, transparent UFO sighting database. We are looking for a talented AI Engineer to help develop this groundbreaking system.
Role: AI Engineer (Computer Vision & Machine Learning)
Location: Remote
Contract Type: Freelance / Full-time
Responsibilities:
🔹 Develop and train deep learning models (CNNs, GANs) to detect manipulated, AI-generated, or authentic UFO images.
🔹 Build a real-time image analysis system capable of categorizing UFO sightings.
🔹 Implement object recognition & anomaly detection to classify spacecraft, weather phenomena, and aircraft.
🔹 Integrate blockchain & decentralized storage (IPFS) for verified image records.
🔹 Develop a user submission & verification portal that allows experts to weigh in on authenticity.
Requirements:
✅ Strong experience in TensorFlow, PyTorch, or OpenCV for image recognition.
✅ Experience with YOLO or other object detection models.
✅ Knowledge of deepfake detection and GAN analysis.
✅ Experience with blockchain for data integrity (Polygon, Ethereum, or Hyperledger).
✅ Ability to process large-scale datasets from online sources & government archives.
Bonus Skills:
⭐ Background in astronomy, aerospace, or remote sensing.
⭐ Experience working with NASA, FAA, MUFON, or other UFO databases.
⭐ Previous work in forensic image analysis & metadata authentication.
Why Join Us?
🚀 Be part of a pioneering AI research project to uncover real UFO sightings.
🔍 Work with leading experts in AI, aerospace, and blockchain.
💰 Competitive pay in crypto, UTOP.
📩 Apply Now! Send your portfolio, GitHub, and resume. Let’s reveal the truth together! 👽📡
Payment in Crypto
Jack Morty
Junior Recruiter (Startup)
Part time
Remote
Job Title: Junior Recruiter (Startup)
📌 Responsibilities:
Sourcing candidates for various roles (IT, marketing, sales, etc.).
Conducting initial screenings and interviews.
Managing candidate databases and maintaining communication throughout the hiring process.
Posting job openings on different platforms and social media.
Collaborating with department heads to identify hiring needs.
📌 Requirements:
6+ months of experience in recruitment or a strong desire to learn.
Understanding of sourcing techniques and candidate search methods.
Proficiency in job boards, and social media recruitment.
Ability to conduct interviews and assess candidates effectively.
Strong communication and organizational skills.
English at an Intermediate+ level (preferred).
📌 What We Offer:
Flexible schedule (remote).
Opportunity to grow in a dynamic startup environment.
Training and mentorship from the team.
Competitive salary.
📩 Interested? Send us your resume! 🚀
📌 Responsibilities:
Sourcing candidates for various roles (IT, marketing, sales, etc.).
Conducting initial screenings and interviews.
Managing candidate databases and maintaining communication throughout the hiring process.
Posting job openings on different platforms and social media.
Collaborating with department heads to identify hiring needs.
📌 Requirements:
6+ months of experience in recruitment or a strong desire to learn.
Understanding of sourcing techniques and candidate search methods.
Proficiency in job boards, and social media recruitment.
Ability to conduct interviews and assess candidates effectively.
Strong communication and organizational skills.
English at an Intermediate+ level (preferred).
📌 What We Offer:
Flexible schedule (remote).
Opportunity to grow in a dynamic startup environment.
Training and mentorship from the team.
Competitive salary.
📩 Interested? Send us your resume! 🚀
Payment in Crypto
Everyvote
Backend Developer
New York, USA
New York, USA
Full time
Remote
About Us:
GP Vote is an innovative startup dedicated to transforming the democratic process through a cutting-edge voting platform integrated with blockchain technology. Our mission is to empower individuals to voice their opinions and shape collective decisions in a secure and transparent environment. We believe that every voice matters, and our platform fosters inclusivity by allowing users to propose titles and suggestions.
We are seeking a talented Frontend Developer with a strong background in React and TypeScript. The ideal candidate will have experience in Web3 and blockchain technologies, enabling them to contribute to our mission of delivering high-quality digital products.
Key Responsibilities:
Lead the migration of our backend systems from Express.js to ASP.NET.
Design, develop, and maintain scalable and secure backend services.
Collaborate with front-end developers to integrate user-facing elements using server-side logic.
Implement data storage solutions and ensure data integrity.
Develop and maintain APIs for mobile and web applications.
Optimize applications for maximum speed and scalability.
Monitor and troubleshoot issues in the production environment.
Stay updated with emerging technologies and trends in backend development, Web3, and Blockchain.
Required Qualifications:
Proven experience as a Backend Developer or similar role.
Strong proficiency in ASP.NET and C#.
Deep knowledge of backend development principles and best practices.
Proficient in database management (SQL, NoSQL).
Understanding of RESTful APIs and microservices architecture.
Experience with version control systems (e.g., Git).
Preferred Qualifications:
Experience with Web3 technologies (e.g., Ethereum, smart contracts).
Familiarity with Blockchain concepts and decentralized applications (dApps).
Knowledge of containerization technologies (Docker, Kubernetes).
Familiarity with CI/CD pipelines and DevOps practices.
Understanding of security best practices in backend development.
Benefits:
Competitive salary and performance-based bonuses.
Flexible working hours and remote work options.
Generous vacation policy and paid time off.
Health, dental, and vision insurance.
Professional development opportunities and access to online courses.
Collaborative and inclusive company culture.
Opportunities to work on cutting-edge technology in the Web3 and Blockchain space.
Team-building activities and company retreats.
How to Apply:
If you are excited about the opportunity to work with a forward-thinking company and have the skills we’re looking for, please send your resume and a cover letter to larry@everyvote.xyz.
Join us in shaping the future of voting technology!
GP Vote is an innovative startup dedicated to transforming the democratic process through a cutting-edge voting platform integrated with blockchain technology. Our mission is to empower individuals to voice their opinions and shape collective decisions in a secure and transparent environment. We believe that every voice matters, and our platform fosters inclusivity by allowing users to propose titles and suggestions.
We are seeking a talented Frontend Developer with a strong background in React and TypeScript. The ideal candidate will have experience in Web3 and blockchain technologies, enabling them to contribute to our mission of delivering high-quality digital products.
Key Responsibilities:
Lead the migration of our backend systems from Express.js to ASP.NET.
Design, develop, and maintain scalable and secure backend services.
Collaborate with front-end developers to integrate user-facing elements using server-side logic.
Implement data storage solutions and ensure data integrity.
Develop and maintain APIs for mobile and web applications.
Optimize applications for maximum speed and scalability.
Monitor and troubleshoot issues in the production environment.
Stay updated with emerging technologies and trends in backend development, Web3, and Blockchain.
Required Qualifications:
Proven experience as a Backend Developer or similar role.
Strong proficiency in ASP.NET and C#.
Deep knowledge of backend development principles and best practices.
Proficient in database management (SQL, NoSQL).
Understanding of RESTful APIs and microservices architecture.
Experience with version control systems (e.g., Git).
Preferred Qualifications:
Experience with Web3 technologies (e.g., Ethereum, smart contracts).
Familiarity with Blockchain concepts and decentralized applications (dApps).
Knowledge of containerization technologies (Docker, Kubernetes).
Familiarity with CI/CD pipelines and DevOps practices.
Understanding of security best practices in backend development.
Benefits:
Competitive salary and performance-based bonuses.
Flexible working hours and remote work options.
Generous vacation policy and paid time off.
Health, dental, and vision insurance.
Professional development opportunities and access to online courses.
Collaborative and inclusive company culture.
Opportunities to work on cutting-edge technology in the Web3 and Blockchain space.
Team-building activities and company retreats.
How to Apply:
If you are excited about the opportunity to work with a forward-thinking company and have the skills we’re looking for, please send your resume and a cover letter to larry@everyvote.xyz.
Join us in shaping the future of voting technology!
Payment in Crypto
DynamicX
Full Stack Engineer
Baiern, Germany
Baiern, Germany
Full time
Remote
About Us
At DynamicX, we're revolutionizing the way sports enthusiasts invest in their passions. Founded by Nicolas Weiner, Tristan Reinthaler, and Gerd Weiner, our innovative platform merges the excitement of sports with cutting-edge financial technology.
Our mission is to empower sports fans to turn their enthusiasm into smart investments, transforming the traditional sports industry landscape. We believe that by combining sports enthusiasm with strategic financial markets, we can create new opportunities for both fans and athletes alike.
Our journey began with a simple idea: what if sports fans could invest in the very athletes and teams they cheer for? This sparked a movement to democratize access to sports investment and create a more engaging, interactive experience for sports enthusiasts worldwide.
At DynamicX, we're committed to innovation, transparency, and community engagement. Our team of passionate technologists, financial experts, and sports enthusiasts works tirelessly to develop cutting-edge solutions that bridge the gap between sports enthusiasm and smart investing.
Join us in shaping the future of sports investment and turning your passion into a career-defining opportunity.
Job Summary
We're looking for a talented Full Stack Engineer who excels in creating robust, scalable, and efficient web applications. You will play a crucial role in developing and maintaining our core platform, working closely with our cross-functional team to deliver high-quality features and improvements. Your expertise in both front-end and back-end technologies will be invaluable in shaping the future of sports investment.
Responsibilities
Design, develop, test, and deploy full-stack web applications using modern technologies
Collaborate with product managers, designers, and other engineers to understand requirements and create solutions
Implement scalable backend services using Node.js, Express, or similar frameworks
Develop responsive and performant front-end interfaces using React, Vue.js, or similar libraries
Integrate third-party APIs and services effectively
Optimize application performance and maintain high code quality standards
Participate in code reviews and contribute to improving team processes
Troubleshoot production issues and implement bug fixes promptly
Stay up-to-date with industry trends and emerging technologies
Requirements
Bachelor's degree in Computer Science or related field (or equivalent experience)
Minimum 3 years of experience in full-stack development
Proficiency in JavaScript (ES6+) and TypeScript
Experience with modern front-end frameworks (React, Vue.js, or similar)
Strong understanding of backend technologies (Node.js, Express, etc.)
Familiarity with databases (MongoDB, MySQL, etc.) and ORM tools
Knowledge of RESTful APIs and GraphQL
Experience with cloud platforms (AWS, Azure, or Google Cloud)
Version control experience with Git
Strong problem-solving skills and attention to detail
Excellent communication and teamwork abilities
Preferred Qualifications
Experience with blockchain technologies
Knowledge of sports-related APIs or platforms
Familiarity with cryptocurrency trading systems
Experience with automated trading systems
Understanding of tokenization concepts
Certification in cloud computing or DevOps
What We Offer
Competitive salary
Comprehensive health insurance package
Flexible hybrid remote work arrangement
Generous PTO policy (20 days annual leave + 10 paid holidays)
Professional development opportunities
Stock options in a growing startup
Access to cutting-edge technologies and tools
Collaborative and dynamic work environment
Opportunities for career growth and advancement
At DynamicX, we're revolutionizing the way sports enthusiasts invest in their passions. Founded by Nicolas Weiner, Tristan Reinthaler, and Gerd Weiner, our innovative platform merges the excitement of sports with cutting-edge financial technology.
Our mission is to empower sports fans to turn their enthusiasm into smart investments, transforming the traditional sports industry landscape. We believe that by combining sports enthusiasm with strategic financial markets, we can create new opportunities for both fans and athletes alike.
Our journey began with a simple idea: what if sports fans could invest in the very athletes and teams they cheer for? This sparked a movement to democratize access to sports investment and create a more engaging, interactive experience for sports enthusiasts worldwide.
At DynamicX, we're committed to innovation, transparency, and community engagement. Our team of passionate technologists, financial experts, and sports enthusiasts works tirelessly to develop cutting-edge solutions that bridge the gap between sports enthusiasm and smart investing.
Join us in shaping the future of sports investment and turning your passion into a career-defining opportunity.
Job Summary
We're looking for a talented Full Stack Engineer who excels in creating robust, scalable, and efficient web applications. You will play a crucial role in developing and maintaining our core platform, working closely with our cross-functional team to deliver high-quality features and improvements. Your expertise in both front-end and back-end technologies will be invaluable in shaping the future of sports investment.
Responsibilities
Design, develop, test, and deploy full-stack web applications using modern technologies
Collaborate with product managers, designers, and other engineers to understand requirements and create solutions
Implement scalable backend services using Node.js, Express, or similar frameworks
Develop responsive and performant front-end interfaces using React, Vue.js, or similar libraries
Integrate third-party APIs and services effectively
Optimize application performance and maintain high code quality standards
Participate in code reviews and contribute to improving team processes
Troubleshoot production issues and implement bug fixes promptly
Stay up-to-date with industry trends and emerging technologies
Requirements
Bachelor's degree in Computer Science or related field (or equivalent experience)
Minimum 3 years of experience in full-stack development
Proficiency in JavaScript (ES6+) and TypeScript
Experience with modern front-end frameworks (React, Vue.js, or similar)
Strong understanding of backend technologies (Node.js, Express, etc.)
Familiarity with databases (MongoDB, MySQL, etc.) and ORM tools
Knowledge of RESTful APIs and GraphQL
Experience with cloud platforms (AWS, Azure, or Google Cloud)
Version control experience with Git
Strong problem-solving skills and attention to detail
Excellent communication and teamwork abilities
Preferred Qualifications
Experience with blockchain technologies
Knowledge of sports-related APIs or platforms
Familiarity with cryptocurrency trading systems
Experience with automated trading systems
Understanding of tokenization concepts
Certification in cloud computing or DevOps
What We Offer
Competitive salary
Comprehensive health insurance package
Flexible hybrid remote work arrangement
Generous PTO policy (20 days annual leave + 10 paid holidays)
Professional development opportunities
Stock options in a growing startup
Access to cutting-edge technologies and tools
Collaborative and dynamic work environment
Opportunities for career growth and advancement
Payment in Crypto