Senior Fullstack Engineer – Backend Focus

Proxima

Senior Full Stack Engineer building AI-driven products at Proxima. Focusing on backend services and AI orchestration while collaborating in a hybrid environment.

Posted 5/29/2026full-timeNew York City • New York • 🇺🇸 United StatesSenior💰 $150,000 - $190,000 per yearWebsite

Tech Stack

Tools & technologies

ReactSQLTypeScript

About the role

Key responsibilities & impact

Design, build, and document backend services and APIs that power our AI-driven products
Develop end-to-end features across AI agent interfaces, orchestration layers, and developer-facing tools
Query, model, and manage relational databases — own the data layer, not just consume it
Build and scale the systems that turn cross-brand transaction data into product
Ship responsive, clean UIs in TypeScript and React where the product needs them
Own projects from architecture to deployment in an agile, high-velocity environment
Collaborate cross-functionally to ship high-impact features quickly
Stay current on modern AI development practices and tooling

Requirements

What you’ll need

6+ years of professional software development experience
Strong backend proficiency in TypeScript, with solid working knowledge of SQL and relational database design
Demonstrated experience building or integrating AI-powered applications — agents, orchestration, or LLM-backed systems
Proven track record in startup environments — you've shipped fast and worn multiple hats
Comfortable owning projects independently in high-velocity environments
Working proficiency in React and the ability to build production UIs when the work calls for it
Daily use of AI-assisted coding tools (Cursor, GitHub Copilot, Claude Code, etc.) — this is a requirement, not a nice-to-have
Bachelor's degree or higher in Computer Science, Engineering, or a related field

Benefits

Comp & perks

Competitive base salary and meaningful equity
Comprehensive medical, dental, and vision coverage
HSA and FSA options
401(k)
12 weeks of fully paid parental leave
Unlimited PTO
Summer Fridays from July 4th through Labor Day
Mental health and wellness support through Talkspace, Health Advocate, and One Medical
Commuter benefits
$1,000 annual learning & development stipend
Quarterly team events, both in and out of the office

ATS Keywords

✓ Tailor your resume

Applicant Tracking System Keywords

Tip: use these terms in your resume and cover letter to boost ATS matches.

Hard Skills & Tools

TypeScriptSQLrelational database designAI-powered applicationsorchestrationLLM-backed systemsbackend servicesAPIsresponsive UI developmentagile development

Soft Skills

project ownershipcollaborationindependenceadaptabilityfast-paced environment

Certifications

Bachelor's degree in Computer ScienceBachelor's degree in Engineering