Full Stack Engineer

Rheaction; San Francisco (CA); On-site; USD 130,000 - 180,000; Full time

Benefits offered by this job

Equity

Job summary

Rheaction is seeking a highly capable Full Stack Engineer to own and build user-facing experiences from end to end. You will work across frontend, backend, and data layers with ownership to ship features and iterate based on user feedback.

The role emphasizes product focus, UX instincts, and rapid experimentation in a fast-moving early-stage environment. In-person work in San Francisco is typical.

Qualifications

• Strong full-stack software engineering skills.
• Solid understanding of databases, data modeling, APIs, and application architecture.
• Strong frontend development capabilities.
• Genuine product intuition and UX focus.
• Experience shipping real applications or features to production.
• Ability to optimize performance and latency.
• Ownership and independence in work.
• Ability to thrive in a fast-moving early-stage environment.

Responsibilities

• Build and own user-facing web and mobile experiences end to end.
• Ship high-quality features from concept through production.
• Work across frontend, backend, APIs, and databases.
• Design and improve data models as the product and user base scale.
• Optimize application performance, latency, and API patterns.
• Build intuitive experiences that simplify complex workflows.
• Partner directly with users to understand pain points and identify opportunities.
• Run product experiments and use data and user behavior to guide decisions.
• Contribute to technical architecture and engineering decisions.
• Continuously improve product quality, reliability, and usability.

Skills

Full-stack engineering

Databases & data modeling

APIs & application architecture

Frontend development

UX usability

Production deployments

Performance optimization

User research & feedback

Job description

Location: San Francisco, CA — In Person

Employment: Full-time
Experience: 0–5 years
Compensation: $130,000–$180,000 + equity

About the Role

We're looking for a highly product-minded Full Stack Engineer to own and build user-facing experiences from end to end.

This role is ideal for a strong engineer who combines full-stack technical depth with excellent product and UX instincts. You'll work across frontend, backend, and data layers while thinking deeply about how real users interact with what you build.

You'll have significant ownership and the freedom to experiment, ship quickly, learn from users, and continuously improve the product.

What You'll Do

• Build and own user-facing web and mobile experiences end to end.
• Ship high-quality features from concept through production.
• Work across frontend, backend, APIs, and databases.
• Design and improve data models as the product and user base scale.
• Optimize application performance, latency, and API patterns.
• Build intuitive experiences that simplify complex workflows.
• Partner directly with users to understand pain points and identify opportunities.
• Run product experiments and use data and user behavior to guide decisions.
• Contribute to technical architecture and engineering decisions.
• Continuously improve product quality, reliability, and usability.

What We're Looking For

• Strong full-stack software engineering skills.
• Solid understanding of databases, data modeling, APIs, and application architecture.
• Strong frontend development capabilities.
• Genuine product intuition and an eye for UX, usability, and interaction design.
• Experience shipping real applications or features to production.
• Ability to think through performance, latency, scalability, and data requirements.
• Strong engineering fundamentals and attention to technical quality.
• High ownership and ability to operate independently.
• Strong problem-solving skills and willingness to work from first principles.
• Interest in understanding users rather than building exclusively from specifications.
• Ability to thrive in a fast-moving, early-stage environment.

Strong Candidates May Have

• Experience at an early-stage or rapidly scaling startup.
• Built and launched their own apps, products, or side projects.
• Previous founder or founding-engineer experience.
• Mobile development experience.
• Experience building consumer-facing products.
• Experience with analytics, experimentation, or A/B testing.
• Strong design sensibility alongside engineering skills.
• Open-source contributions or other independently shipped technical work.

A traditional background or specific university pedigree isn't required. We value evidence that you can build, ship, learn quickly, and take ownership.