Internal Systems Developer Intern (f/m)
Founded in 2014, Ledger is a globally recognized platform that aims to democratize access to digital assets and Web3 technology. Ledger is at the forefront of the industry, securing over 20% of the world's crypto assets with its Ledger Nanos. The company is headquartered in Paris and Vierzon, with additional offices in the UK, US, Switzerland, and Singapore. Ledger boasts a diverse team of over 500 professionals dedicated to developing products and services that empower individuals and businesses to securely purchase, store, exchange, grow, and manage their crypto assets.
Ledger prides itself on its core values of Pragmatism, Audacity, Commitment, Trust, and Transparency, which are integral to the company's identity and operations. As part of the dedicated Internal Systems team, you will contribute to the development and maintenance of essential tools built on PHP/Symfony that support Ledger's operations and success. In this role, you will collaborate with a team of experts and closely liaise with various departments within the company.
Your responsibilities will include working alongside a team of nine professionals to enhance internal tools related to order management, shipping, and invoicing. You will tackle a wide range of technical and functional challenges, engage with different teams such as E-commerce, Sales, Finance, and Shipping & Logistics to address their requirements, and actively participate in team and sprint meetings to showcase your contributions.
The ideal candidate for this role is a computer science student with a level of Bac+3 to Bac+5, possessing a strong foundation in PHP or a similar language. Additionally, proficiency in SQL, GIT, object-oriented programming, and fluency in French and English are required. A collaborative spirit, a passion for teamwork, and a keen interest in sharing and adopting best development practices are highly valued qualities.
In return for your contributions, Ledger offers a range of benefits tailored to enhance your work experience, including a hybrid work policy for flexibility, regular social events with snacks and drinks, access to cutting-edge office equipment and gadgets, partial reimbursement of transportation costs, lunch vouchers through Swile, and additional vacation days based on tenure.
A commitment to equality and diversity is ingrained in Ledger's ethos, and the company serves as an equal opportunity employer, welcoming individuals of all backgrounds and identities.
Senior Software Engineer (Blockchain)
MentTech is a forward-thinking technology company dedicated to transforming how mentoring and learning are delivered in the digital age. By combining advanced tools, intelligent systems, and a human-first approach, MentTech helps individuals, teams, and organizations harness the power of mentorship to unlock potential, build skills, and achieve lasting growth.
The Role
We are seeking a Smart Contract Developer responsible for ensuring that game listings within MentTech work properly and ensuring compliance with all game store policies.
Key Responsibilities:
• Architect, implement, and deploy secure smart contracts for an on-chain Play-to-Earn GameFi ecosystem
• Lead contract design decisions with a focus on robustness, auditability, gas efficiency, and resilience to attack vectors
• Mentor/junior developers: perform code reviews, establish standards, best practices in security & testing
• Collaborate cross-functionally with game designers, backend, QA, and security teams to align smart contract features with product roadmap
Qualifications:
• 2+ years hands‐on experience developing & deploying smart contracts (Solidity / EVM or equivalent) in production environments
• Track record of writing secure contracts, familiarity with common vulnerabilities (reentrancy, integer over/underflow, front-running, flash loans, etc.)
• Experience with audits, formal verification, fuzz testing, or other advanced contract assurance methods
• Strong test suite / CI workflow skills; comfortable using tools like Hardhat, Foundry, Truffle etc.
• Solid understanding of GameFi mechanics and how on-chain economics work
Bonus Points:
• Experience on multiple EVM chains or Layer-2 / sidechains
• Knowledge of cross-chain bridges, oracles, NFTs, tokenomics design
• Contributions to open-source security tooling or prior audit reports or published code you’re proud of
Why join MentTech?
At MentTech, we cultivate a culture of flexibility, autonomy, and the freedom to make a real impact on the broader Web3 ecosystem. Experience the advantages of a fully remote working environment where your expertise and contributions are rewarded with competitive compensation tailored to your role and project influence.
Ment Tech Labs
• Employee Equity & Incentives: Unlock future growth with equity and other potential incentives.
• Entrepreneurial Culture: Join a collaborative environment where we innovate together as partners.
• Cutting-edge Innovation: Work at the forefront of gaming and blockchain.
• Key Strategic Projects: Be part of transformative initiatives that are redefining the gaming landscape.
• Remote Flexibility: Enjoy a truly flexible, fully remote work setup that supports your lifestyle.
• Talented Team: Collaborate with a team of passionate, driven, and skilled professionals.
• Community Impact: Contribute to the growth and success of the Web3 and gaming communities.
• Flexible Payment Options: Receive payments in crypto or fiat, tailored to your preference.
• Growth Opportunities: Access valuable learning experiences and development paths.
MentTech Labs, Inc. is an equal opportunities workplace that doesn’t discriminate based on race, ethnicity, gender, ancestry, national origin, religion, sex, sexual orientation, gender identity, age disability, veteran status, genetic information, marital status, or any other legally protected status.
Senior web3 engineer
We’re building a SocialFi platform combining real estate and DeFi. After launching our MVP, we’re now progressing to version 2.
Role:
Join our remote team to develop website, smart contracts, integrate blockchain features, and ensure platform security.
Responsibilities:
- Develop and deploy smart contracts on Ethereum or Layer 2.
- Integrate wallet connect and decentralized features.
- Collaborate and direct contribute with frontend/backend teams.
- Conduct security audits.
Requirements:
- Experience with React, Ethers.js, Web3.js.
- Familiarity with wallet extensions and DeFi protocols.
- Ability to fix errors within 1 hour during tests.
- Comfortable working independently in a remote setup.
Nice to Have:
- Knowledge of cross-chain protocols or cryptography.
- Experience in social finance or real estate blockchain projects.
Application:
Send your resume and Linkedin profile. Selected candidates will do a quick coding test.
Contact: contact@hubsai.net
Join us to help shape the future of SocialFi!
Junior / Middle Metaverse Developer (Unity / Web3 / VR)
You will work with Unity, WebGL, and blockchain technologies to create engaging metaverse features and optimize them for performance across different devices. The developer will collaborate with designers and backend engineers to deliver scalable and stable products.
Requirements include experience with Unity and C#, understanding of 3D development, Web3 or blockchain basics, and familiarity with Git and API integration. Experience with VR/AR, NFTs, or multiplayer systems is a plus.
We offer remote work, flexible hours, crypto payments, and the opportunity to build innovative metaverse products.
Junior/Mid Decentralized Infrastructure Engineer
Help build and scale decentralized infrastructure: contribute to compute networks, protocols, storage layers, and orchestration tools that power AI agents and open digital systems. You’ll write code, run tests, fix bugs, and ship real features fast.
Skills & Requirements:
1–3 years in blockchain infra, distributed systems, or high-scale compute (or strong personal projects)
Solid Python / Rust / Go skills
Interest in libp2p, IPFS, GPU orchestration, or decentralized compute
Quick learner who ships clean code and loves performance/cost challenges
Salary:
$110,000 – $165,000 USD base + meaningful equity (portfolio startup) + full benefits + Sirex carry
Description:
Sirex.vc doesn’t just invest — we plug strong builders straight into our portfolio companies.
This is your chance to work on the real infrastructure behind autonomous agents and the open digital economy. Full support from the Sirex team, fast growth, zero bureaucracy.
High risk. Zero apologies.
Web3 Fullstack Developer
Neonflick is a tech organization specializing in Web3 development.
We believe Web3 solutions are not as popular as they could be — mainly due to complexity. Our mission is to simplify the user experience and make decentralized technology more accessible and easy to use for everyone.
🚀 About the Role
We are looking for a Web3 Fullstack Developer who is passionate about decentralized technologies and excited to contribute to building meaningful Web3 products. You will work on developing new products, improving existing ones, and fixing bugs, all while proposing innovative ideas to enhance our platform.
🔹 Responsibilities
Develop functional and user-friendly Web3 products
Improve and optimize existing products and features
Identify and fix bugs or issues in the system
Propose and implement new ideas for product development
Collaborate with the team to ensure high-quality software delivery
🔹 Requirements
Strong interest in Web3 / blockchain / decentralized technologies
Fullstack development experience (frontend + backend)
Experience with smart contracts and decentralized frameworks is a plus
Problem-solving skills and attention to detail
Ability to work independently and proactively
🔹 What You Get
Early-stage involvement in a Web3 tech organization
Influence over product development and feature design
Opportunity to build experience and a portfolio in the Web3 space
Potential long-term collaboration and future compensation as the project grows
A chance to contribute to making Web3 simpler and more accessible
⚠️ Important
This is an unpaid position. We are looking for someone motivated by vision, learning, and long-term impact rather than immediate salary.
If you are passionate about Web3 and building meaningful decentralized products, we’d love to hear from you.