Variational - Fullstack Engineer

Variational is building a protocol for peer-to-peer trading, clearing, and settlement of perpetuals and generalized derivatives. As a Fullstack Engineer at deCircle, you'll be primarily frontend-focused, responsible for building trading interfaces and product experiences across the company's applications. You'll work in a small, high-ownership environment where you own and deliver frontend systems end-to-end, supported by strong in-house design and product leadership.

What you'll do

• Build and own frontend trading interfaces using TypeScript and Svelte or equivalent modern frameworks
• Implement fullstack features, including backend API development in Rust, Go, or Python
• Optimize performance across frontend and backend through CDNs, SSR, and real-time data systems
• Own frontend security, including secure coding practices, XSS/CSRF prevention, and deployment/DNS configuration
• Implement fullstack security measures such as SQL injection prevention, JWT authentication, and WAF configuration
• Maintain CI/CD pipelines, containerized deployments, and end-to-end test automation

What you bring

• 5+ years of fullstack development experience using modern technologies, with strong understanding of both frontend and backend performance optimization
• Strong proficiency in TypeScript
• Extensive experience with Svelte (preferred), React, Vue, or similar modern frameworks
• Backend or fullstack experience to ensure a well-rounded engineering skillset
• Strong proficiency in SQL and extensive experience working with relational databases
• Advanced knowledge of frontend and fullstack security, including XSS/CSRF prevention, JWT authentication, WAF configuration, and SQL injection prevention

Nice to have

• Experience with trading platforms, dashboards, DeFi, or similar domains
• Experience integrating crypto wallets
• Rust proficiency
• SvelteKit proficiency
• Experience with PostgreSQL and Redis
• Strong design sense and UX mindset
• Security expertise and the ability to own frontend security end-to-end

About deCircle

deCircle is backed by leading investors including Bain Capital Crypto, Peak XV, Coinbase Ventures, Dragonfly, Hack VC, and others, having raised over $50M. The team is currently around 15 people, predominantly engineers, and is planning to double or triple in size over the next two quarters.