Top Senior Full-Stack Engineer Jobs in Boston, MA

Owner of Vannevar's authentication and authorization platform: build tenant-isolated auth systems, self-service user/group/permission admin UI, tooling to visualize and validate access, feature-flag and platform management interfaces, and shared authorization capabilities across products.

Senior full‑stack engineer responsible for building production-quality Salesforce platform capabilities, integrations (MuleSoft, REST/SOAP), AI-enabled tooling (Claude plugins, MCP servers), CI/CD, and reusable libraries. Mentor engineers, run architecture/code reviews, and collaborate cross-functionally to deliver scalable, secure cloud-native solutions using Python, LWC, Apex, and AWS.

Design, develop, and deliver fullstack web solutions, optimize platforms, mentor engineers, and manage product features from ideation to launch.

The Senior Fullstack Engineer will deliver software products, collaborate with product and business teams, lead technical practices, and ensure high-velocity iteration on a mobile advertising platform.

The Senior Full-Stack Engineer will develop claims monitoring tools and backend services, collaborate with other engineers, and influence the product architecture in a health insurance startup.

Own and implement end-to-end product features across the stack (React/TypeScript front end, Ruby on Rails backend, relational DBs, GCP infra). Design APIs and data models, ensure performance and reliability, integrate AI/LLM-powered features, collaborate with product/design/clinical teams, perform code reviews, and mentor junior engineers.

Build and ship full‑stack growth experiments end-to-end to improve acquisition, activation, engagement, and monetization. Collaborate with product, design, and analytics, analyze experiment results, iterate quickly, and contribute to experimentation platform and growth infrastructure while balancing speed, quality, and long-term maintainability.

Senior fullstack engineer to build and scale Brigit's consumer finance platform. Own end-to-end features across frontend (React/React Native/TypeScript) and backend (Java/REST/SQL), optimize database and APIs for high scale, integrate 3rd-party services, implement risk and transaction algorithms, improve CI/CD, testing, monitoring, and internal tooling to support millions of users.

Build end-to-end data and analytics features: ingest and model data, build transformations and pipelines, create client-facing dashboards and interfaces, and develop LLM-powered workflows to accelerate analysis and app development. Partner with stakeholders, perform exploratory analyses, and ensure data quality, observability, and maintainability while influencing data engineering strategy.

Build and ship full-stack features for a production AI/LLM platform: implement polished React UIs from specs, own database and access-control/security, integrate multi-provider LLMs (RAG, agentic workflows), and formalize QA by extending test suites with integration and end-to-end coverage.

Hands-on senior full stack engineer to design, code, review, and ship web front ends and backend APIs. Lead technical execution for a small team, define architecture and API contracts, integrate AI/LLM features (tool calling, prompt/control flow), support secure enterprise integrations, and mentor engineers through code review and pairing.

Lead full-stack engineering across client engagements: architect, build, deploy, and maintain web applications, APIs, CMS implementations, and CI/CD workflows. Own technical client relationships, enforce best practices, evaluate AI-enabled development, and support long-term maintenance while balancing accessibility, security, performance, and project constraints.

Build and productionize LLM-backed agents and workflows: create eval harnesses, observability, provenance and human-review surfaces, extend agent capabilities (web/CMS, OAuth), implement pipeline orchestration, and ship scoring/ranking models and reusable modules to scale across clients.

Build and maintain Grafana Cloud integrations and observability features across frontend (TypeScript/React), backend (Golang), and monitoring mixins (Jsonnet). Ship end-to-end features, own projects to production, contribute upstream to OpenTelemetry/Prometheus, run on-call for owned services, and communicate designs and demos across teams.

Build and ship full-stack features for North, develop autonomous agents that access sensitive enterprise data, productionize state-of-the-art models, write minimal, secure low-resource code, and collaborate with researchers to deploy performant RAG/agentic applications while prioritizing security and user experience.

As a Senior Fullstack Engineer, you will enhance products for hotel distribution, architect scalable solutions, and mentor team members. You'll work with PHP and JavaScript frameworks, focusing on performance and security while collaborating across teams to deliver high-quality features.

As a Senior Full-Stack Engineer, lead development of secure AI-driven SaaS applications, focusing on backend architecture, frontend design, and AI integrations. Collaborate with teams to operationalize models and enhance application functionality through cutting-edge AI solutions.

Design, build, and own scalable, secure full-stack applications. Collaborate with engineers, designers, and managers to gather requirements, estimate work, maintain documentation, and deliver high-quality client-facing software using Agile practices.

Design and implement full-stack applications for GenAI, build developer tooling, collaborate with product teams, and enhance AI agent delivery.

Design and build agent-powered mission consoles, collaborate with stakeholders to improve user workflows, and maintain agentic workflows for mission outcomes.

As a Senior Software Engineer, you will design and build a cutting-edge identity search platform and implement AI systems for defense applications, working closely with cross-functional teams to enhance user workflows and support national security.

Build end-to-end features in a JS/TS stack, designing scalable backend services and responsive real-time frontends. Improve observability, performance, and reliability, collaborate with product/design, and own full-stack implementation from APIs and data models to UI.

Build and maintain core platform features, expand Infisical PKI/SSH/KMS product lines, collaborate with CTO and engineers, communicate with enterprise customers, and prototype AI applications for secrets management.

The Sr. Full Stack Developer will design and build full-stack applications, focusing on AI-powered solutions, and lead code reviews while mentoring junior engineers in the Advanced Technology Center.

Design, architect, and build full-stack web applications and AI-powered solutions integrating LLM APIs, RAG pipelines, vector databases, and agentic frameworks. Lead code reviews, mentor engineers, support PoC engagements, and maintain cloud-native, containerized deployments with CI/CD best practices. Advocate AI-augmented engineering workflows and produce technical documentation for ATC lab environments and customer-facing prototypes.