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.
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.
Junior AI Engineer
Join one of our fast-growing portfolio startups and help build simple AI features. You’ll work with large language models, create basic automations and chat tools, test ideas, fix small bugs, and integrate AI into everyday products.
Skills & Requirements:
0–2 years of experience (fresh graduates or self-taught welcome)
Basic Python knowledge
Interest in AI, LLMs or chatbots (personal projects are a big plus)
Quick learner who enjoys trying new things
Good English for team communication
Salary: $95,000 – $135,000 USD base + equity in the startup + full benefits
Description:
Sirex.vc not only invests — we actively help our portfolio companies hire great people. This Junior AI Engineer role is inside one of our AI-native startups. You’ll get real hands-on experience, learn from the best, and build things users actually use — all with full support from the Sirex team.
High risk. Zero apologies.
Full Stack Developer – Kick-to-Earn Gaming Platform
We're building a mobile-first competitive gaming platform where players step onto the virtual field and earn rewards through penalty kick matches. The platform includes real-time gameplay, tournaments, leaderboards, an in-app store, token management (deposit/withdraw), daily quests, and a player progression system. Think casual gaming meets Web3 — fast, competitive, and rewarding.Current StateThe frontend is actively under development with a strong foundation already in place:
~30+ reusable UI components (modals, tabs, cards, buttons, inputs, badges, etc.)
Multiple feature modules: penalty game, tournaments, leaderboard, user profiles, store, token management
Figma-driven design system with a polished dark-themed UI
Animated goalkeeper characters using Lottie/dotLottie with SVG body parts
SPA routing and responsive mobile-first layouts
Tech Stack
Frontend: Next.js 16, React 19, TypeScript, Tailwind CSS 4
Animations: Lottie / dotLottie
Design Pipeline: Figma with MCP integration for design-to-code workflow
Tooling: ESLint, PostCSS, Turbopack
What You'll Do
Build and maintain frontend features with pixel-accurate implementation from Figma designs
Architect and develop backend services (APIs, authentication, game logic, matchmaking, token transactions)
Integrate blockchain/token functionality for the earn-and-spend economy
Design and manage the database layer (user data, match results, tournament state, transaction history)
Set up real-time infrastructure for live matches and leaderboard updates
Write clean, scalable TypeScript across the full stack
Collaborate closely with design to maintain high visual fidelity
Requirements
3+ years of production experience with React and Next.js
Strong TypeScript skills
Solid backend experience (Node.js, Express/Fastify/Hono, or similar)
Database design and management (PostgreSQL, MongoDB, or equivalent)
Experience building and consuming REST or GraphQL APIs
Understanding of real-time systems (WebSockets, SSE, or similar)
Proficiency with Tailwind CSS and responsive, mobile-first design
Comfort working from Figma designs with attention to detail
Nice to Have
Experience with Web3 / blockchain integrations (wallet connection, token transactions)
Familiarity with Lottie animations and interactive game-like UIs
Experience with matchmaking or game server architecture
Knowledge of payment/transaction systems
Experience with CI/CD pipelines and deployment (Vercel, Docker, etc.)
If you enjoy building products at the intersection of gaming and crypto, and you care about clean architecture and polished UI, we'd love to hear from you.Feel free to adjust the engagement type, compensation details, timezone preferences, and any company-specific info before posting.