Flagship Pioneering · 5 hours ago
Principal Backend Developer
Cambridge, MA
Full-time
Onsite
Senior Level, Lead/Staff
$152K/yr - $209K/yr
8+ years expFlagship Pioneering is a company that empowers entrepreneurs and D2C brands with AI-driven tools for product innovation. The Principal Backend Developer will be a technical leader responsible for architecting, building, and scaling core backend systems while mentoring engineers and influencing technical strategy.
FinanceFinancial ServicesVenture Capital
Responsibilities
Own Core Backend Systems – Design, build, and maintain scalable services, APIs, and platform infrastructure. Ensure reliability, observability, and maintainability
Drive Large-Scale Data Pipelines – Architect and operate high-volume, resilient data pipelines for ingestion, transformation, and analytics
Lead Third-Party Integrations – Build and maintain integrations with external vendors, ensuring reliability, observability, and long-term maintainability
Influence Architecture & Best Practices – Shape backend architecture, coding standards, testing frameworks, CI/CD pipelines, and operational excellence
Mentor & Lead Engineers – Provide guidance on system design, debugging at scale, and engineering practices
Wear Multiple Hats – Support DevOps, troubleshooting, or other platform needs when necessary
Qualification
Required
8+ years of backend engineering experience
Bachelor's degree in Computer Science, Software Engineering, or equivalent practical experience
Strong expertise in backend languages and frameworks (Node.js/TypeScript, Go, Python, or similar)
Experience designing scalable distributed systems, microservices, and event-driven architectures
Deep experience with third-party integrations, REST/GraphQL APIs, webhooks, and rate-limited services
Proficiency with SQL/NoSQL databases, data pipelines, and performance optimization
Familiarity with cloud platforms (AWS, GCP) and containerized/deployed systems (Docker, Kubernetes)
Strong testing, CI/CD, and observability practices
Comfortable working in a fast-paced, evolving environment with minimal oversight
Preferred
Experience building and shipping features quickly in early-stage startups
Exposure to multiple backend domains (analytics, payments, notifications, workflow orchestration)
Hands-on experience with serverless or edge architectures for rapid iteration
Familiarity with low-friction integrations with third-party tools and SaaS platforms
Track record of scaling systems from small MVPs to production-ready services
Comfort with ambiguity and making trade-offs between speed, quality, and maintainability
Benefits
Healthcare coverage
Annual incentive program
Retirement benefits
Broad range of other benefits
Company
Flagship Pioneering
Flagship Pioneering is a venture capital firm that invests in life sciences and healthcare companies.
501-1000 employees
H1B Sponsorship
Flagship Pioneering has a track record of offering H1B sponsorships. Please note that this does not
guarantee sponsorship for this specific role. Below presents additional info for your
reference. (Data Powered by US Department of Labor)
Distribution of Different Job Fields Receiving Sponsorship
Represents job field similar to this job
Trends of Total Sponsorships
2025 (8)
2024 (4)
2023 (4)
2022 (4)
2021 (1)
Funding
Current Stage
Late StageLeadership Team
Noubar Afeyan
Founder and CEO
Chuck Carelli
Chief Financial Officer
Recent News
2026-01-16
2026-01-16
Company data provided by crunchbase