Circle is looking for a Senior Full-Stack Software Engineer to join our Applied AI team. You will leverage AI to drive innovation for customers by building transformative applications of large language models. In this role, you will spearhead the development of full-stack AI solutions across the company.
What You'll Do
- Ship full-stack AI projects end-to-end on a product built in Ruby on Rails backend and React frontend.
- Design and run experiments, including A/B tests on AI evaluations, to validate features, measure impact, and guide iteration.
- Build and integrate components for AI infrastructure and optimize them for performance and reliability to support production-level inferencing.
- Improve processes, tools, and systems to scale AI features into production-ready solutions.
- Help us stay up-to-date with the latest AI research, techniques, and tools.
- Work closely with Circle's leaders throughout the feature design process.
- Work closely with our designers to create a high-quality user experience.
- Foster a bias for action by prioritizing speed of iteration, experimentation, and learning, while maintaining high standards of code quality and user experience.
What We're Looking For
- 5+ years experience working as a full-stack engineer on complex web applications with significant scale (100k+ rpm, 100GB+ databases).
- Strong proficiency in Ruby on Rails, MySQL / PostgreSQL, and ReactJS. Familiarity with both frontend and backend is necessary.
- Strong experimentation mindset—comfortable designing and running A/B tests, measuring results, and iterating quickly.
- A desire to work in an environment which values speed of iteration and individual autonomy, while also embracing personal accountability and collaboration.
- Comfortable in a fast-paced environment with a certain level of ambiguity, especially when learning and picking up new technologies.
- Strong alignment with our values.
- Proficient in English (spoken, written, and reading) at a CEFR Level C2 / ILR Level 5.
Nice to Have
- Experience building backend systems and infrastructure for AI-driven products.
- A track record of working on full-stack AI projects, including deploying at least 1 production-ready use case of LLMs at scale.
Technical Stack
- Ruby on Rails
- MySQL
- PostgreSQL
- ReactJS
Team & Environment
You'll join the Applied AI team within a fully remote company of around 200 (and growing!) team members from 30+ countries.
Benefits & Compensation
- Salary: $130,000 - $140,000 USD per year + startup equity.
- Fully remote: work from anywhere in the world!
- Autonomy and trust to do your job: we care about outcomes over everything else.
- Paid time away: all employees are given 35 days of PTO annually.
- Paid sabbatical after 5 years.
- Generous U.S. benchmarked compensation and startup equity no matter where you are in the world.
- Awesome medical coverage with 100% coverage for you and your family, or medical reimbursement options where applicable!
- Parental leave for parents expanding their family.
- Home office stipend to help you get up and running.
- Learning & development stipend to help you level up your professional skills.
- Annual bonus potential for roles that don't already receive variable income or commission.
- Company retreats: Twice a year, the Circle team gets together for a fully paid company retreat.
Work Mode
This is a fully remote position open to candidates globally.
Circle is an equal opportunity employer and as such, we do not discriminate on the basis of race, color, religion, sex, sexual orientation, gender identity, national origin, age, disability, or any other characteristic protected by applicable laws.
