Web3 Full-stack Developer Jobs in San Francisco, United States

Company overview

Infinite is a stablecoin payment processor. We offer businesses turnkey APIs and SDKs to instantly move money anywhere in the world at a fraction of the cost of traditional solutions. The founding team previously built and scaled products at financial services category leaders Coinbase and Sardine.

The opportunity

As our Founding Engineer, you will define, build, and maintain the technical foundation of our platform. You will join us in-person in a fast-paced, high-ownership environment where you will take ownership of everything, from architecture and implementation to production reliability for mission-critical services. You will partner directly with founders and early customers to translate real-world requirements into robust, high-quality products.

Key responsibilities

1. Full Stack & End-to-End – Design, implement, and operate complete services and user-facing features, from requirements gathering through production support

2. System Design & Architecture – Develop highly available, event-driven systems for ledgering, compliance, and risk that scale with transaction volume while maintaining zero downtime

3. Implementation Engineering – Embed with customers, collect feedback, and iterate rapidly to ensure our roadmap aligns with user needs

4. Technical Decision-Making – Balance speed and long-term scalability, selecting appropriate technologies (Next.js/TypeScript, C#, Go, Python, modern cloud infrastructure) for each problem domain

Required skills & experience

• 2–5+ years of professional software engineering, including the delivery of 0-to-1 products and scaling them in production

• Proficiency in at least two of: Next.js/TypeScript, C#, Go, Python

• Hands-on expertise with asynchronous and event-driven architectures

• Full-stack ownership spanning modern front-end frameworks, back-end services, and cloud infrastructure

• Excellent written and verbal communication; ability to influence internal and external cross-functional stakeholders

• Proven expertise with AI-assisted development tools—especially Cursor or windsurf, to accelerate code generation, refactoring, and automated test creation

Preferred qualifications

• Practical experience deploying lightweight machine-learning models for real-time anomaly detection, automated compliance reporting, or incident triage in production systems

• Experience designing and contributing to fintech, payments, or ledgering systems (e.g., double-entry ledgers, payments, clearing, or settlement)

• Experience integrating banking, payments, or compliance providers, or a demonstrated ability to onboard unfamiliar financial APIs quickly

• Prior leadership or mentorship in a high-growth engineering team

Ideal candidate

The ideal candidate is a passionate and driven engineer with a hacker's mindset. You are comfortable both leading a team and being hands-on with code. You thrive in fast-paced environments and are eager to tackle complex challenges that drive our company's success.