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# Senior Full-Stack Software Engineer (JavaScript)

- **Company:** Sp Global, Inc.
- **Location:** Cambridge, MA, United States
- **Experience:** Expert
- **Salary:** $150,000 - $225,000
- **Contract:** Permanent contract
- **Skills:** LangGraph Framework, JavaScript (Programming Language), Artificial Intelligence, Amazon Web Services, Github, Prometheus, Next.js, Software Engineering, TypeScript, Web Applications, Web Performance Optimization, Tailwind, ReactJS, Langfuse — LLM Observability and Analytics Platform, Git, Sentry
- **Published:** October 14, 2026
- **Apply:** https://www.indeed.com/viewjob?jk=c22babf42a5124e8

## About the Role

* At least five years of direct experience building commercial web applications in JavaScript/TypeScript
 * At least three years of that experience working directly on web UIs in a modern framework
 * At least one domain of deep technical expertise (e.g., web performance, design systems, framework knowledge, etc.)
 * Product sense, or a strong interest in developing it
 * Kind, thoughtful, and high-signal communication skills for both technical and non-technical audiences
 * Ability to translate ambiguous needs and constraints into clear technical requirements

Technologies & Tools We Use:

 * Development : TypeScript, React, Next.js, Tailwind, LangGraph, AI SDK, Drizzle
 * Ops : Git, GitHub, Amazon EKS, AWS, Sentry, Langfuse, Prometheus

## Description

As a Senior Full-Stack Software Engineer, you will build AI-centric web applications in TypeScript ranging from experimental POCs to full-fledged product offerings. You'll have significant autonomy over technical and architectural choices, and be responsible for managing short- and long-term trade-offs. The ideal candidate loves product and views technology as a means, not an end, and is excited to collaborate across all aspects of the software development lifecycle.