Principal Backend Engineer
Flagship Pioneering, Inc. · Cambridge, MA USA
Posted 22 days ago · $188,000 - $258,500
or apply directly on Flagship Pioneering, Inc.'s site. We never take the application ourselves.
Is this posting real?
- This role has been open
- 22 days Flagship Pioneering, Inc.'s roles stay open a median of 45 days
- Reposted
- No
- Salary listed
- Yes 89% of Flagship Pioneering, Inc.'s roles list one
- Ghost-job risk at Flagship Pioneering, Inc.
- high 50 stale, 1 reposted of 100 open
- Hiring momentum
- 144 roles opened in the last 90 days ↑ up vs. the prior 90 days
- Last confirmed on the employer's board
- 2026-09-17
Measured from postings appearing on and disappearing from Flagship Pioneering, Inc.'s own greenhouse board since 2026-08-03. Full hiring picture for Flagship Pioneering, Inc..
About this role
As a Principal Backend Engineer at Extuitive, you will lead the architecture, development, and scaling of core backend systems for an AI-driven platform. Your responsibilities include designing high-throughput services, managing data pipelines, and integrating with third-party services while ensuring system reliability and security. You will also influence technical strategy and best practices, and support various platform needs as they arise.
- benefits
- 2/5
- freshness
- 4/5
- career value
- 4/5
- role clarity
- 5/5
- pay transparency
- 5/5
Scored from the posting itself — how clearly the role is described, how much it says about pay and benefits, and how recently it was listed. Not a judgement of Flagship Pioneering, Inc. as an employer.
What you need
- 8+ years of backend engineering experience
- Experience with high velocity agentic coding under strict security requirements
- 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
Nice to have
- 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
What you get
- Healthcare coverage
- Annual incentive program
- Retirement benefits
- Broad range of other benefits
Worth weighing
- Salary range provided is quite broad ($188,000 - $258,500) and may vary based on qualifications and experience.
- The role involves working in a fast-paced environment which may require adaptability to changing requirements.
- The company operates like a 'special ops unit', indicating a high-pressure work culture.
Summarised from Flagship Pioneering, Inc.'s posting. Read the full original.
Listed by Flagship Pioneering, Inc. on their greenhouse job board, last confirmed open on 2026-09-17. PitchMeAI is not the employer.
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