Top Senior Full-Stack Engineer Jobs in Boston, MA

Design, build, and operate production-grade Java-based enterprise applications and microservices. Implement RESTful APIs, front-end features with React, and relational database schemas and tuning. Deploy and manage applications on AWS/Azure/GCP using CI/CD, containerization, and observability practices. Perform debugging, troubleshooting, and root-cause analysis; contribute to architecture and DevOps practices.

Senior technical leader responsible for end-to-end architecture and technical direction of a performance measurement and attribution calculation platform. Own cross-cutting design, lead cross-team integration, prototype and adopt AI/ML, mentor senior engineers, and write code for the hardest problems to ensure performance and correctness at scale.

Design, develop, test, and maintain firmware, user interfaces, PC applications, and web services for machine vision sensors. Lead scrum stories, drive design reviews and code quality, mentor junior developers, integrate core vision features, debug customer issues, and collaborate with product, marketing, and support teams to meet milestones.

Lead design and implementation of the PSA Liquidity Platform connecting buyers and sellers. Build buyer tooling, matching/ranking engines, and seller experiences. Architect and operate microservices and Kafka-driven systems on Kubernetes/AWS, instrument observability, apply AI tooling across the SDLC, and drive cross-functional delivery from 0-to-1 while owning end-to-end outcomes.

Design, develop, test, deploy, and maintain full‑stack web applications. Build front-end interfaces, back-end logic, APIs and databases; troubleshoot accessibility and performance; integrate with Salesforce; create automated tests, prototypes and documentation; participate in code reviews and continuous improvement.

As a Full Stack Engineer III at Calendly, you'll develop features, scale the platform, and mentor team members while using various technologies.

Design, build, and maintain production-grade .NET web applications and APIs on Azure. Own full-stack delivery from data models and SQL to front-end components, CI/CD, testing, and architecture. Collaborate with product and delivery teams, participate in code reviews, and ensure secure, observable, well-tested services.

Lead end-to-end full-stack development across React frontends and compiled backends, influence architecture and data modeling, integrate third-party dealership APIs, use AI-assisted coding tools daily, set engineering standards, ship production features to live dealership users, and mentor junior engineers.

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 ship end-to-end features across a TypeScript/Next.js monolith: dashboard, marketing site, billing, email, and AI-assisted tools. Own data models, APIs, third-party integrations, testing, observability, and production quality. Collaborate with the founder, review code, and improve engineering practices while delivering customer-facing features rapidly.

Design, build, and maintain AI-powered B2B SaaS products across frontend, backend, and AI. Own projects end-to-end, collaborate with product and design, ensure maintainability, mentor teammates, and inform roadmap and implementation decisions.

The Senior Fullstack Software Engineer will design, implement, and maintain features for Conveyor's SaaS platform, involving both backend and frontend work, while collaborating closely with team members and mentoring juniors.

Design, build, and optimize scalable cloud and web software with focus on infrastructure, performance, and hardware integration for IoT devices. Collaborate with hardware teams to ensure connectivity and high availability, implement new features, and improve system efficiency.

Design, develop, and maintain scalable web applications using React front ends and .NET 8 back ends. Build RESTful APIs and microservices, implement CI/CD with GitHub Actions, troubleshoot performance issues, participate in architecture and code reviews, and mentor junior engineers while collaborating with cross-functional teams.

Design, build, and operate customer-facing features for a React+Vite portal and the AWS backend services that power it. Lead TypeScript migrations, optimize performance, create reusable design-system components, and maintain unit and BDD/e2e tests (Playwright/Cypress). Implement IoT communication (MQTT, WebSockets, AWS IoT Core), event-driven architectures (SQS, SNS, EventBridge), and CI/CD pipelines. Instrument services for observability and collaborate across product, design, firmware, and hardware teams.

Build and maintain full-stack product and AI systems: React/React Native frontends, Node.js services, LLM-powered features (agents, RAG), integrations, monitoring, and scalable automation. Ship production features, ensure reliability, and mentor teammates.

Design, build, and own scalable multi-tenant SaaS applications across frontend, backend, and data layers. Improve system architecture, performance, reliability, and testing practices. Integrate AI-assisted tools, mentor engineers, conduct code reviews, and collaborate with Product and Design to deliver intuitive, production-grade software.

Lead and mentor engineers to design, build, and own the Integrations Platform powering 400+ integrations. Drive complex, cross-team projects, set technical direction, develop product functionality and infrastructure using modern frameworks, and enable scalable, declarative integration-building, including AI-enhanced tooling.

Design, build, and maintain scalable backend services and APIs for millions of users. Collaborate with product and UX, implement automated testing, participate in on-call incident management, and mentor teammates while delivering complex distributed-system projects.

Lead end-to-end feature development across API (Node.js), web (React/Next.js), and mobile (React Native). Scope, design, implement, test, and ship production systems; drive architecture and scalability for an AWS-backed, real-time IoT fleet; partner with product and raise engineering standards.

Build and maintain full-stack production applications and services that integrate frontier LLMs. Design, test, and stress-test systems, diagnose failures, prototype rapidly, and collaborate with engineering and research teams to deliver reliable, deployable software and evaluation tooling.

Design, build, and operate scalable backend systems and APIs across a distributed service-oriented architecture. Own features end-to-end, partner with product stakeholders, ship shared infrastructure, and maintain high code quality. Participate in an on-call rotation and collaborate in a distributed North American team to deliver reliable, high-performance user experiences.

Design and deliver scalable backend systems and APIs, own features end-to-end, drive technical direction, collaborate with product stakeholders, build shared infrastructure, and participate in on-call rotations.

Work primarily on backend Node.js services within a large cloud-native platform while contributing to frontend integrations. Design APIs, support serverless and workflow orchestration, implement event-driven processing, improve reliability, optimize data models, and support deployment, monitoring, and incident resolution. Collaborate with distributed teams to ship end-to-end features, conduct code reviews, and evolve system architecture.

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.