Senior Software Engineer – Frontend/React (USA Only, 100% Remote)

ABOUT US Since 2013, we’ve been building a CRM that gets out of your way and helps your team sell more, faster. Now we’re building AI into every part of it, so Close does the busywork and your team does the selling. No manual data entry, no 10-click workflows. Just communication-first, AI-powered sales software designed to help you succeed and scale. We're bootstrapped and profitable which means we answer to our customers and play by our rules. We're proud of our 120-person, 100% remote team, focused on building Close so that no small, scaling business fails because it can't figure out sales. OUR STACK Our frontend is a single-page TypeScript web app built in React. We bundle with Vite and target modern browsers only. We test with Vitest, React Testing Library, Playwright, and Chromatic for visual regression. Our UI updates in near real-time using WebSockets and WebRTC, is styled via CSS modules, and is performance-tuned with route-based code splitting and skeleton UI. We've built our own design system, documented in an extensive Storybook. We sweat the UI/UX details and work collaboratively with Product throughout the design process - from lo-fi wireframes through Figma and into code. Our frontend is built on top of our REST API and GraphQL endpoints, backed by a Python/Flask/FastAPI, MongoDB, Postgres and Elasticsearch stack running on AWS. We love open sourcing our code and ideas on our GitHub https://github.com/closeio and on The Making of Close https://making.close.com/, our behind-the-scenes Product & Engineering blog. Check our projects such as react-custom-scroller https://making.close.com/posts/introducting-react-custom-scroller-component, use-infinite-scroll https://making.close.com/posts/introducting-use-infinite-scroll-react-hook, use-abortable-effect https://making.close.com/posts/introducting-use-abortable-effect-react-hook, and smart-tooltip-delay https://making.close.com/posts/introducing-smart-tooltip-delay-library or insights from our day-to-day work like Under the Hood: Developing Close's AI-Powered Call Assistant https://making.close.com/posts/developing-the-call-assistant, Cutting our Lead page LCP by half https://making.close.com/posts/cutting-our-lead-page-lcp-by-half, and Highlights From a Complex Downshift.js Refactor https://making.close.com/posts/highlights-from-a-complex-downshift-js-refactor/. AI is both how we build and what we ship, and that's reshaped what engineering looks like. This is a transformation we’re embracing and find deeply exciting. OUR TEAMS When you apply, you’ll have an opportunity to highlight the team that appeals to you the most. We’ll do our best to honor this preference, but we'll also be evaluating skillset fit and the needs of the business. One thing to know up front: we do move people between teams as the work shifts. Most engineers here end up on more than one team over their time at Close - this team is where you’ll start, but over time you’ll likely have the opportunity to work on many different projects. The work splits roughly like this. Pick the team that excites you most: - Agents. Build the UI that puts AI in the hands of Close customers. This means the creation and configuration experiences for Close's growing family of agents, the conversational interface through which users ask questions and get answers in plain language, and the observability surfaces that let customers see what their agents are doing and why. The design challenges here are genuinely new: you'll be figuring out how AI capabilities should surface in the product.

• Communications. Own the UI for one of the most real-time, high-stakes surfaces in Close: calls. You'll build in-call experiences that run on WebRTC and WebSockets, live transcript and coaching views where latency visibly matters, power dialing flows built for reps making hundreds of calls a week, and the email, SMS, and scheduling surfaces that keep async outreach moving.
• CRM.

• Growth. Own the surfaces that turn someone who just signed up into a paying customer who sticks around.

• Building AI-powered interfaces. You've shipped LLM-backed features for real users and have a POV on where they're trustworthy, where they fall over, and how to make them feel reliable when customers bet their workflow on the output.

• Working with AI daily. You use AI tools in your own workflow to ship faster, write tighter code, and reason about unfamiliar parts of the codebase. We fund the use of AI tools (Claude Code, Codex, and other best-in-class developer tools) and treat learning and experimentation as part of the work.
• A builder first.

• Opinionated about UI craft and component design. You've built reusable systems that other engineers loved using, and you think about who's on the other end — sales reps in the middle of a call, power users who live in the keyboard, and customers who just need it to work.
• Battle-tested.

Compensation

• 80% Work Option: Work with your manager to choose between a standard 5-day week or a 4-day week at 80% pay - Parental Leave: Paid leave for primary and secondary caregivers - Sabbatical: A 1-month paid sabbatical every 5 years with the team - Healthcare (US residents): Two medical plans with Close covering 99% of your premium, plus Dental, Vision, HSA, FSA, and company-paid Long-Term Disability - 401k (US residents): We match your contributions up to 6%, vested immediately OUR VALUES Build a house you want to live in - Examine long-term thinking and action No BS - Practice transparency and honesty, especially when it’s hard Invest in each other - Build successful relationships with your coworkers and customers Discipline equals freedom - Keep your word to yourself and others Strive for greatness - Constantly challenge yourself and others LEARN MORE Listen to our CEO and Founder, Steli Efti, tell the story of Close’s journey in the $0-30m Blueprint https://www.close.com/blueprint.

• Ensure your portfolio showcases your frontend development skills, especially with React and TypeScript.
• Practice explaining complex technical concepts in simple terms, as this will be valuable in a collaborative environment.
• Be prepared to talk about your experience with UI/UX design principles and how you have applied them in previous roles.
• Highlight any experience you have with AI or machine learning, even if it's not directly related to frontend development.
• Prepare questions about the company culture, the team you will be working with, and how success is measured in this role.
• Show enthusiasm for the company's mission and products, and be ready to discuss how you can contribute to its growth and success.