Lead Full Stack Software Engineer (AI Agents)

Lead Full Stack Software Engineer (AI Agents)

Location: New York City (Onsite)

Compensation: $175,000–$300,000 Base + Bonus + Equity

About the Opportunity

We're partnering with a well-funded AI software company that's building next-generation autonomous AI agents for commercial contract review and legal workflows.

This is not a traditional enterprise software role. You'll join a small, highly technical engineering team building AI-native products from the ground up. Working directly with company founders and senior technical leadership, you'll help create intelligent agents that automate complex legal analysis and dramatically improve how contracts are reviewed and negotiated.

If you're excited about agentic AI, LLMs, and shipping products quickly in a startup environment, this is an opportunity to make a significant impact.

What You'll Do

• Design, build, and deploy full-stack applications powering AI-driven legal workflows.
• Develop autonomous AI agents capable of analyzing, reviewing, and reasoning over commercial contracts.
• Build intuitive user experiences that make sophisticated AI capabilities accessible to enterprise customers.
• Collaborate closely with product, AI, and engineering leaders on product architecture and technical direction.
• Integrate large language models into production applications.
• Build scalable APIs and backend services supporting AI-powered workflows.
• Improve application performance, reliability, and security across the technology stack.
• Take ownership of features from concept through production deployment.

Required Technical Skills

You should have strong experience across the modern full-stack ecosystem, including:

• Python
• TypeScript
• React
• JavaScript
• SQL or another relational database
• Git
• CI/CD pipelines
• REST APIs

Experience working with OpenAI, Anthropic, or other modern large language models is highly preferred.

AI Experience

We're specifically looking for engineers who have built AI-powered products—not just experimented with them.

Ideal candidates have experience developing:

• AI agents
• Autonomous workflows
• Chatbots
• Agentic systems
• LLM-based applications
• Prompt engineering
• Retrieval-Augmented Generation (RAG)
• Multi-agent architectures

Daily use of AI-assisted development tools such as Cursor, Codex, Claude Code, or similar is strongly preferred.

Ideal Background

Successful candidates will typically have:

• 5–10 years of software engineering experience (up to approximately 15 years considered).
• Strong full-stack development experience.
• Experience at both:
• A large, established technology company (approximately 18+ months), and
• A startup with fewer than 100 employees (or experience founding a startup).
• A track record of shipping production software in fast-moving environments.
• Experience thriving in ambiguous, high-growth organizations.

We're Looking For Someone Who

• Loves building products from scratch.
• Enjoys solving difficult technical problems.
• Moves quickly while maintaining high engineering standards.
• Thinks like an owner.
• Is excited by AI-first software development.
• Can balance product thinking with technical excellence.
• Wants significant influence over architecture and product direction.

Compensation & Benefits

• Base salary: $175,000–$300,000
• Annual performance bonus
• Equity opportunity
• Comprehensive medical, dental, and vision coverage
• 401(k) with company match
• Paid parental leave
• Flexible PTO and generous company holidays
• Professional development budget
• Leadership coaching
• Employee wellness programs
• Opportunity to help shape an early-stage AI product with significant market potential

This is a full-time onsite position based in New York City.

Who is Rainier Recruiting? 

Rainier Recruiting is a boutique, award winning national staffing agency and executive search firm. Using an approach that “treats every candidate like an executive search”, we offer positions in contract-to-hire, Full-Time, and executive search. Named the #1 Best Workplace in Washington State in 2022, recognized as a ClearlyRated Best of Staffing firm, and identified as a top recruitment firm by multiple business journals, Rainier Recruiting is fast becoming a respected company. We are no longer the “best recruiters you have never heard of”. Rainier Recruiting is also proud to share our clients have a 93% repeat business rate. Rainier Recruiting is an equal opportunity employer and service provider and does not discriminate on the basis of race, religion, gender, gender identity, national origin, citizenship status, sexual orientation, disability, political affiliation or belief, or any other protected class. We are committed to the principles of Equal Opportunity Employment and are dedicated to making employment decisions based on merit and value, for ourselves, our client companies, and for the candidates we represent. We engage in socially conscious business practices and believe that diverse, equitable, inclusive, and non-biased talent and recruitment processes are foundational to the success of every organization that we partner with.