Crush

Senior Full Stack Mobile Engineer (Web3 & Fintech)

Crush

24 days ago

## The Mission Crush Rewards is building the ultimate bridge between traditional consumer behavior and the decentralized future. We’re not just another rewards app; we’re a contribution network where everyday actions—like scanning a receipt and linking credit card spending—are transformed into on-chain value. We are looking for a **Full Stack Mobile Engineer** who thrives at the intersection of high-performance mobile interfaces, robust backend architecture, and the Solana blockchain. You will own features end-to-end: from crafting a "buttery-smooth" UI to architecting the backend pipelines that verify financial data and trigger token emissions. ## What You’ll Do * **Architect the Frontend:** Lead the development of our React Native (Expo) app, ensuring high-performance execution of complex features like real-time token charts and deep-linked wallet interactions. * **Build Robust Backend Pipelines:** Own the Node.js/Express API that powers our ecosystem. You'll manage critical backend logic including receipt OCR verification, transactional syncs with credit cards, product rewards calculations, and user progression systems (streaks, levels, milestones). * **Execute Web3 Strategy:** Implement and scale our Solana integration. You will manage custodial wallet flows with Crossmint, execute on-chain token swaps via Jupiter, and handle complex staking/unstaking logic. * **Own the Data Lifecycle:** Manage a scalable PostgreSQL architecture, ensuring real-time data consistency across user profiles, streaks, and transaction histories. * **Iterate with Quality:** Advocate for best practices in TypeScript, automated testing, and CI/CD (EAS/GitHub Actions) to ensure we ship high-quality code to the App Store and Play Store multiple times a week. * **Drive Growth through Data:** Use PostHog analytics and OneSignal engagement tools to understand user behavior and build the features that keep our users "Crushing" their goals. ## What You’ll Need * **The TypeScript Professional:** You have 4+ years of experience in professional software engineering, with a mastery of TypeScript across the entire stack. * **Mobile Expertise:** Deep experience with **React Native (Expo)**. You understand the mobile lifecycle, performance optimization, and how to build responsive UIs using modern toolkits. * **Backend Proficiency:** Strong experience with **Node.js** and **PostgreSQL**. You know how to design clean APIs and manage complex relational data at scale. * **Web3 Literacy:** You are comfortable with the **Solana ecosystem** (web3.js, SPL tokens). You understand how to interact with smart contracts and manage the security implications of blockchain transactions. * **Fintech Experience:** Practical experience integrating third-party financial APIs and handling sensitive user data with a "security-first" mindset. * **Product Intuition:** You care about the "Why" behind a feature. You can translate a Figma design into a functional reality while suggesting improvements to the user flow. Bonus points if you can create clean UI components without Figma. ## Our Tech Stack * **Mobile:** React Native, Expo, TypeScript. * **Backend:** Node.js, Express, PostgreSQL, Edge Functions. * **Blockchain:** Solana (Web3.js), SPL Tokens, Crossmint, Jupiter SDK. ## Bonus Points * You’ve built or contributed to a Solana **Anchor** program (Rust) and/or typescript SDKs. * Experience with **AI/LLM pipelines** for data extraction or personalized user experiences. * Background in a high-growth startup where you wore multiple hats and "owned" the outcome. * A passion for the "Rewards" space and an understanding of gamification mechanics (streaks, levels, milestones). ## Why Join Us? At Crush Rewards, we're a small, focused team where every member has significant impact and ownership. You won't just be a "cog in the machine"—you will be the architect of a platform that redefines how millions of people interact with their money and the blockchain. We value clean code, fast iteration, and a relentless focus on the user experience. When applying, mention the word **CANDYSHOP** to show you read the job post completely.