Full-Stack Engineer - Weekend Team

Full-Stack Engineer — Weekend Team Location: Remote Schedule: Thursday–Monday Employment Type: Full-time Onyx is building the consumer trading platform for the speculation economy—bringing prediction markets, sports, crypto, and real-world events into one seamless experience. Following our Series A led by Payward, we’re growing the engineering team behind our real-time trading platform. We’re looking for a Full-Stack Engineer to own critical product development and platform reliability across our Thursday–Monday schedule, when customer activity is at its highest. What You’ll Do Build and ship customer-facing features across the frontend and backend Develop scalable applications using TypeScript, React, Node.js, and PostgreSQL Own projects from technical design through development, deployment, and monitoring Build real-time experiences powered by live data and streaming updates Integrate frontend applications with backend APIs and AWS-based services Monitor platform performance and respond to production issues during high-volume periods Improve application reliability, scalability, testing, and observability Collaborate with Product, Design, Trading Operations, and Engineering Contribute to technical decisions, code reviews, and engineering best practices Help create a smooth handoff between the weekend and weekday engineering teams What We’re Looking For 2+ years of professional full-stack software engineering experience Strong experience with TypeScript, React, Node.js, and SQL Experience building and maintaining production applications Solid understanding of APIs, databases, frontend architecture, and cloud infrastructure Experience with AWS , CI/CD workflows, testing, debugging, and monitoring Comfortable troubleshooting production issues and working across the stack Strong product intuition and attention to customer experience Able to work independently and take ownership in a fast-moving startup Available to work a consistent Thursday–Monday schedule Experience with WebSockets, real-time data, fintech, trading, sports, gaming, crypto, or other high-volume consumer products is a plus Why Onyx High ownership over meaningful, customer-facing work Competitive compensation and meaningful equity Remote position with a consistent Thursday–Monday schedule Opportunity to join a fast-growing company at an early stage Work alongside a team with experience from Jane Street, DraftKings, Robinhood, xAI, and Harvard This is a full-time remote position. Candidates must be authorized to work in the United States; we are unable to provide employment sponsorship at this time.