Senior Software Engineer (Thomas)

Xometry; Waltham (MA); Hybrid; USD 170,000 - 195,000; Full time

Job summary

Xometry is seeking a Senior Software Engineer to join Thomas engineering. You will build and maintain systems behind AI-assisted sourcing, where buyers describe needs and the platform matches them with manufacturers.

You will work closely with a product manager and peer and senior engineers. You will mentor engineers, own design and delivery, and ensure testing and reliability while collaborating across teams to ship features powered by LLMs, retrieval, and search.

Qualifications

• 6+ years of software development experience focused on outcomes.
• Strong full-stack skills in TypeScript/Node.js, React/Next.js, GraphQL, PostgreSQL, OpenSearch.
• Experience building AI-powered features: LLMs, retrieval-augmented generation, vector search.

Responsibilities

• Hands-on technical leadership: coding, reviewing, and setting team patterns.
• Own end-to-end features from design to production, including AI-powered capabilities.
• Mentor engineers through thorough code reviews and best practices.
• Ensure testing and reliability meet customer needs and timelines.

Skills

Full-stack

AI features

LLM applications

OpenSearch

React/Next.js

TypeScript/Node.js

GraphQL APIs

PostgreSQL

Search relevance

LangChain

LangGraph

Multimodal embeddings

Vector search

Tools

LangChain

LangGraph

OpenSearch

Job description

Xometry (NASDAQ: XMTR) powers the industries of today and tomorrow by connecting the people with big ideas to the manufacturers who can bring them to life. Xometry’s digital marketplace gives manufacturers the critical resources they need to grow their business while also making it easy for buyers at Fortune 1000 companies to tap into global manufacturing capacity.

Thomasnet, part of Xometry, is the industrial platform where millions of buyers find and source from North American manufacturers and suppliers.

We are seeking a Senior Software Engineer to join Thomas engineering. Thomas is moving from a traditional supplier directory to AI-assisted sourcing, where buyers describe what they need and the platform does the matching. You will build and maintain the systems behind that shift, from the product experiences buyers and suppliers use every day to the AI-powered features at the center of our strategy. You will work closely with a product manager and peer and senior engineers.

How You'll Contribute

• Hands-on technical leadership. Lead by example by actively coding, reviewing, and troubleshooting. Set good coding patterns and designs for the team.
• Lead projects end-to-end. Own the design and delivery of features within your team, from problem to production and largely independently, including the AI-powered capabilities at the center of our strategy: features that use LLMs, retrieval, and search, with the evaluations and guardrails that keep them accurate and safe.
• Mentorship and code review. Guide and mentor engineers on the team; do thorough code review and raise the bar for how others review.
• Operational excellence. Own testing and reliability for what you ship. Deliver software that meets customer expectations and business timelines.

What You'll Bring

• 6+ years of software development experience, focused on outcomes over output, with a habit of helping shape the team's direction rather than only building to spec.
• Strong full-stack skills that transfer to our stack: backend services in TypeScript and Node.js with GraphQL APIs, a React and Next.js frontend, PostgreSQL, and search such as OpenSearch. Comparable experience in another modern stack counts just as much; prior experience with our exact tools is not required.
• Hands‑on experience building AI‑powered product features: LLM applications, retrieval‑augmented generation, vector search, or search relevance. We hire AI‑native engineers who build with these tools and judge their output rigorously, whatever the specific frameworks.
• Bonus points: experience with multimodal (image and text) embeddings and search, agent orchestration frameworks (e.g. LangGraph, LangChain), and fine‑tuning or adapting models for a domain.
• A fast learner with high agency who works fluently in an AI‑native development environment and shares what they learn. We are all still learning how to build with AI, and we want people who help the team learn faster.
• Strong execution, debugging, and communication skills. Prioritizes unit and integration testing.
• E‑commerce or marketplace product experience is a plus.

The estimated base salary range for new hires into this role is $170,000 – $195,000 annually + annual bonus, depending on factors such as job‑related skills, relevant experience, and location. The total compensation package includes base, bonus, and equity. We also offer a competitive benefits package, including:

#LI-Hybrid

Xometry is an equal opportunity employer. All applicants will be considered for employment without attention to race, color, religion, sex, sexual orientation, gender identity, national origin, veteran, or disability status.

For US based roles: Xometry participates in E-Verify and after a job offer is accepted, will provide the federal government with your Form I-9 information to confirm that you are authorized to work in the U.S.

Voluntary Self-Identification

For government reporting purposes, we ask candidates to respond to the below self-identification survey. Completion of the form is entirely voluntary. Whatever your decision, it will not be considered in the hiring process or thereafter. Any information that you do provide will be recorded and maintained in a confidential file.

As set forth in Xometry’s Equal Employment Opportunity policy, we do not discriminate on the basis of any protected group status under any applicable law.

If you believe you belong to any of the categories of protected veterans listed below, please indicate by making the appropriate selection. As a government contractor subject to the Vietnam Era Veterans Readjustment Assistance Act (VEVRAA), we request this information in order to measure the effectiveness of the outreach and positive recruitment efforts we undertake pursuant to VEVRAA. Classification of protected categories is as follows:

A "disabled veteran" is one of the following: a veteran of the U.S. military, ground, naval or air service who is entitled to compensation (or who but for the receipt of military retired pay would be entitled to compensation) under laws administered by the Secretary of Veterans Affairs; or a person who was discharged or released from active duty because of a service‑connected disability.

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An “Armed forces service medal veteran” means a veteran who, while serving on active duty in the U.S. military, ground, naval or air service, participated in a United States military operation for which an Armed Forces service medal was awarded pursuant to Executive Order 12985.