Principal EngineerBlitzy is a Cambridge, MA based AI software development platform on a mission to revolutionize the software development life cycle by autonomously building custom software to unlock the next industrial revolution. We're transforming how enterprises build software, turning enterprise requirements into production-ready code with an agentic software development platform that can autonomously execute 80% of the quantum of software development work. We're backed by multiple tier 1 investors, and have proven success as founders of previous start-ups.We are hiring a Principal Engineer to take full, hands-on ownership of Blitzy's most critical production-grade systems and to deliver high-leverage features that materially improve customer outcomes and engineering velocity.
This is the most senior individual contributor role at the company today. This is not a Senior-plus role, an architecture-only role, or a promotion-track role. We are looking for someone who has already operated at Principal / Staff+ scope in a highly technical environment and expects to spend their time writing, reviewing, and shipping production code.
This role is 100% hands-on. Leverage comes from system ownership, execution quality, and durable technical decisions — not people management or process.Location: Cambridge, MA (On-Site) Compensation: $280,000 - $320,000 + bonus and equityWhat Success Looks LikeYou independently own mission-critical production systems end-to-endYou ship high-leverage features that materially improve reliability, performance, and customer valueYou raise the technical bar through working code and outcomes, not reviews aloneYou identify and resolve the hardest technical bottlenecks limiting quality or velocityYou make technical decisions with long-term impact and stand behind them in productionYou are a self-directed learner requiring minimal supervisionYou are dedicated to getting things done right without making technical compromisesYou demonstrate strong technical expertise across the full stack: frontend, backend, infrastructure, and AI systemsYou materially increase the effectiveness of the engineering organization through example and judgmentAreas of OwnershipEnd-to-end ownership of production-grade backend systems used by enterprise customersCorrectness, scalability, performance, and operational reliability in real environmentsDelivery and stewardship of high-impact features, not just incremental improvementsBuilding and improving Blitzy using Blitzy, holding the platform to real-world standardsDesigning, operating, and evolving LLM validation loops to ensure correctness, consistency, and durability in productionSetting engineering quality and durability expectations across teams without direct reportsCore Technologies & Required ExperienceThis role demands strong, hands-on experience across the full technology stack. You should have deep expertise in most of the following:BackendPython (primary language)Backend frameworks and microservices architecturesRPC-based services (REST, gRPC)Node.js and JavaScript (supporting languages)Cloud & InfrastructureExpertise across at least two of AWS, GCP, and Azure, with GCP mandatoryExpert-level Kubernetes experience for container orchestration in production environmentsTerraform for infrastructure as codeProduction systems: monitoring, reliability, scalability, and operational toolingDatabases & Data SystemsStrong expertise across both SQL and NoSQL databasesSQL: PostgreSQL, MySQL, or similar relational databasesNoSQL: MongoDB, Cassandra, DynamoDB, or similarGraph databases (Neo4j) for modeling and searching complex relationshipsVector databases / embeddings infrastructure for semantic search and retrievalAI / LLM ToolingExperience building and operating LLM-powered systems in productionDesigning and implementing LLM validation loops (evaluation, feedback, regression testing, and failure analysis)LangSmith (or equivalent tooling) for tracing, evaluation, and debuggingFamiliarity with specific models or vendors (e.g., OpenAI, Anthropic) is a plusFrontend & Full-Stack CompetencyStrong understanding of frontend frameworks and architectureAbility to evaluate and contribute to frontend technical decisionsDemonstrated technical expertise across the full stack — you can debug, design, and ship across frontend, backend, infrastructure, and AI layersEnterprise SystemsCore understanding of how large-scale enterprise systems are designed, integrated, deployed, and operatedExperience working within — or modernizing — complex, long-lived production environmentsWays to Stand OutPrior experience operating at Principal Engineer / Staff+ scope at a highly technical companyDeep understanding of how enterprise software systems are built and evolved at scale, including tradeoffs around reliability, change management, and long-term maintainabilityClear ownership of complex systems that you designed, built, and supported in productionHands-on ownership of LLM validation loops used to ensure correctness and durability in real environmentsExperience designing systems that combine graph, vector, and traditional data models to support reasoning over complex domainsProven ability to deliver outsized impact through the right features, not just more codeTrack record of being a self-learner who requires minimal supervision and gets things done without compromising on qualityCompensationTotal compensation: $300,000 - $500,000This includes a mix of competitive base salary and equity, tailored to demonstrated Principal-level experience, scope of ownership, and production impact.You'll Get…Competitive salary and equityPaid medical, dental, and vision insurance for you and your dependents4% 401(k) matchFlexible vacation days, sick days, and work-from-home daysTechnology (hardware, software, reading materials, etc.) equipment and/or allowanceThe opportunity to re-shape an entire industry and create a platform that changes the future of software creationA beautiful office environment with adjacent offices shared by other startups — an energizing communityUnlimited snacks, fizzy water, coffee, espresso, and whatever else you need to perform at your bestOur CultureWho we are: Led by two pioneering co-founders we are one of the fastest growing companies in the U.S., creating our own category of enterprise autonomous software development.
We automate thousands of hours of software development for our customers, which includes strong representation within the Fortune 500.How we work:We move Blitzy Fast: Time is both our company's and our clients' most precious asset. We move quickly and decisively to innovate internally and deliver exceptional software externally.Championship Mindset: We operate like a professional sports team. We win as a team by holding ourselves and each other to high standards, collaborating in-person, and remaining focused on the mission.Passion for Invention: We're pushing the frontier of what's possible, requiring constant innovation and iteration.We Work for the Customer: We focus on delivering outsized value to the customers we work with and expanding those relationships into deep, meaningful partnerships.