Senior Software Engineer - Frontend/React

About Close

Since 2013, Close has been building a CRM that empowers teams to sell more, faster, by getting out of their way. Focused on communication-first sales software, Close helps SMBs succeed and scale without manual data entry.

As a bootstrapped and profitable company, Close answers directly to its customers, fostering a culture of ownership and meaningful impact among its ~120-person, 100% remote team.

Our Engineering Team

The Engineering team at Close comprises 50+ members across Frontend, Backend, and Infrastructure. They prioritize craftsmanship, collaboration, and are committed to shipping thoughtful, scalable, and innovative solutions that matter to their customers.

The frontend is a single-page TypeScript web app, primarily built with React (originally Backbone.js). Mobile apps use React Native. They bundle with Vite, target modern browsers, and test with Vitest, React Testing Library, Playwright, and Chromatic for VRT. The UI features near real-time updates, styled via CSS modules, and leverages WebSockets and WebRTC.

Close emphasizes performance (e.g., route-based code splitting, skeleton UI), maintainability, and testability. The team works collaboratively with Product throughout the design process, from lo-fi wireframes to Figma and code implementation. They have developed their own design system with an extensive Storybook.

The frontend app interacts with REST API & GraphQL endpoints. The backend stack includes Python/Flask, MongoDB, Postgres, Elasticsearch, and Redis, running services in Docker on AWS.

Close actively open-sources code and shares insights on their GitHub and the 'Making of Close' blog. Notable projects include react-custom-scroller and use-infinite-scroll, with insights on topics like AI-Powered Call Assistant development and performance optimization.

About The Role

You will join one of six cross-functional product development teams (CRM, Growth, Conversations, Messaging & Scheduling, Automations & Integrations, Data Insights). As a Senior Software Engineer - Frontend/React, you will collaborate with other Frontend and Backend Engineers, Product Managers, and Designers to drive initiatives to completion.

Projects you could contribute to include:

• Conceiving, designing, building, and launching new user-facing features.
• Implementing new AI features to enhance customer tasks.
• Working with Twilio's API, WebSockets, and WebRTC to improve calling and SMS.
• Building user-facing analytics features for actionable sales insights.
• Enhancing the web app with real-time updates via GraphQL Subscriptions.
• Improving real-time collaboration user experience.
• Leveraging the latest AI LLMs from providers like OpenAI, Claude Code, and AssemblyAI.
• Expanding frontend GraphQL usage.
• Extending the React component library.

About You

Close is looking for an experienced full-time Senior Software Engineer - Frontend/React with a solid understanding of web technologies, eager to design, implement, and launch major user-facing features.

You are comfortable in a fast-paced, talented, and fully distributed team, adept at managing your time, communicating effectively, and collaborating. You are supported in your professional growth.

Senior 1 & 2 level candidates should possess 5+ years of experience building modern frontend single-page applications with JavaScript, HTML, and CSS, including at least 3 years using React. Staff level candidates require 8+ years. Significant experience in designing, debugging, and optimizing fast, reliable frontend applications is essential. You should have substantial experience with REST APIs and a thorough understanding of HTTP requests. Participation in code reviews and providing code quality suggestions are expected. A strong product sense and a love for great UI, coupled with the ability to think through UX issues before coding, are highly valued. You care deeply about code craftsmanship. Candidates must be located in the USA (ET, CT, MT, PT time zones).

Bonus Points If You Have...

• Experience implementing real-time web apps (e.g., WebSockets, polling).
• Experience working with GraphQL endpoints.
• Utilized models from AI companies like OpenAI, Anthropic, and AssemblyAI in a production web app.
• An eye for design and experience with Figma, Sketch, Abstract, Photoshop, or similar.
• Led small project teams in building and launching features.
• Contributed open source code (core or plugins) for a popular frontend framework.
• Built B2B SaaS products.
• Experience with sales or sales tools.

Benefits

• Competitive compensation including an organization-wide goal-based bonus.
• Paid Time Off: 4+ weeks upon joining + 2 extra days annually, plus six paid US holidays including Winter and Summer breaks.
• Paid Parental Leave for primary and secondary caregivers.
• Sabbatical: 1 month paid after 5 years with the team.
• Healthcare (US residents): Medical, Dental, Vision with HSA option, Dependent care FSA.
• 401k (US residents): 6% match with immediate vesting.

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 CEO and Founder, Steli Efti, tell the story of Close’s journey in the $0-30m Blueprint. Watch their culture video from the 2023 team retreat in Milan, or explore their product demo. The entire team gathers in person annually for connection and collaboration; the 2026 retreat will be in Barcelona, Spain.

Our Hiring Process

The application process includes role-specific questions to learn more about you beyond your resume. While generative AI tools are powerful, exclusive reliance on them is discouraged unless explicitly stated, as all applications are read by humans. You will receive an update on your candidacy, and successful applicants will get a full outline of the interview process in their first touchpoint.

Key skills/competency

• React Development
• TypeScript
• Frontend Architecture
• UI/UX Design
• GraphQL
• WebSockets
• RESTful APIs
• Performance Optimization
• Cross-functional Collaboration
• Agile Methodologies