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Founding Backend Engineer

RainesDev

Job TitleJob InformationDate Opened 10/07/2025Job Type: Full timeIndustry: TechnologyWork Experience: 4-5 yearsSalary: 180000 to 230000City: San FranciscoState/Province: CaliforniaCountry: United StatesZip/Postal Code: 94102Job DescriptionAbout the company Our client is building the AI-enabled infrastructure to power the next generation of hiring – reimagining how people discover and secure their next career opportunity. We believe that everyone deserves an all-star talent agent helping them plan, manage, and accomplish their career goals, no matter their background, location, or education. Through our flagship product, Copilot, we've helped over 1M+ job seekers discover and apply to over 100 million jobs - and we've done this with a tight-knit team of just 7 people. We're rapidly expanding on both the candidate and recruiter fronts, focused on our vision of building a common app and personal AI agent for your career. Backed by top-tier investors including Craft and YCombinator, we're a mission-driven team working to democratize the job search and disrupt the way hiring works today.Roles and Responsibilities Design, develop, and maintain scalable backend services to help us serve millions of users daily. Work closely with the product team to launch new features. Collaborate with frontend engineers to design and implement RESTful APIs and shared API client libraries. Architect and manage deployment of our cloud infrastructure on GCP. Ensure high performance, reliability, and security of backend systems.Job Requirements Seniority 4+ years of experience Python backend development experience--mid to senior career level preferred, though exceptional candidates with less experience will be considered if they have strong Python expertise and experience scaling large systems. Work experience Track record of building production-grade backend services from scratch Previous experience as a founder or founding engineer is highly preferred. Hard skills Strong Python backend development expertise Demonstrated ability to scaffold and set up projects independently. Knowledge of GCP and cloud-based scaling solutions. Experience with SQL optimization, protocols, and backend infrastructure. Node.js/TypeScript experience Simplify is looking for incredible senior software engineers willing to do IC. They should be fluent in AI, including OpenAI/Claude API & AI dev tools (Cursor, Windsurf, Devin, etc.). Miscellaneous Must be willing to work in-office 4+ days per week Must be comfortable in early-stage startup environment (team of 7, doubling to 14) Active GitHub profile or contributions to open-source projects (especially in the Python ecosystem). Traits to avoid No Python experience: This is a hard filter. Lack of scalability experience: Candidates should have worked on systems handling high traffic. Contract or staffing firm backgrounds: These candidates are less likely to meet the bar.

Vacancy posted 3 days ago
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