Fullstack Software Engineer, Applied AI

At Lang Chain, our mission is to make intelligent agents ubiquitous. We build the foundation for agent engineering in the real world, helping developers move from prototypes to production-ready AI agents that teams can rely on. What began as widely adopted open-source tools has grown into a platform for building, evaluating, deploying, and operating agents at scale.

Today,
Lang Chain, Lang Graph, Lang Smith, and Agent Builder are used by teams shipping real AI products across startups and large enterprises. Millions of developers trust Lang Chain to power AI teams at companies like Replit, Clay, Coinbase, Workday, Lyft, Cloudflare, Harvey, Rippling, Vanta, and 35% of the Fortune 500
.

With $125M raised at Series B from IVP, Sequoia, Benchmark, Capital

G, and Sapphire Ventures
, we’re at a stage where we’re continuing to develop new products, growth is accelerating, and all team members have meaningful impact on what we build and how we work together. Lang Chain is a place where your contributions can shape how this technology shows up in the real world.

We’re hiring Applied AI Engineers to help us build AI agents that power every part of Lang Chain from Marketing and GTM to Recruiting, Support, Internal Tools, and our Core Product.

In this role you will own a problem space and work closely with that function to design, build, and deploy production-grade agents, workflows, and applications that transform how we operate. Your work will directly accelerate Lang Chain’s mission to make intelligent, autonomous software a reality both internally and for our customers. Some of these projects will be open source
, contributing to the Lang Chain and Lang Graph ecosystem and setting new standards for how companies build with AI.

If you are a fullstack software engineer who is passionate about putting AI agents into real production use cases and seeing them drive measurable business impact, this team is for you.

* This role is based in our San Francisco or New York office. Employees within commuting distance work from the office five days per week. Candidates who live outside commuting distance (e.g. >1hr each way), may be eligible for hybrid arrangements depending on location and role requirements.

• Design, implement, and deploy end-to-end AI workflows and agents that solve real problems across multiple business domains.
• Develop and iterate on agent architectures, evaluation pipelines, and performance frameworks to ensure reliability and measurable outcomes.
• Translate emerging AI research and tooling into practical, production-ready solutions.
• Communicate technical decisions, trade-offs, and insights clearly to both technical and non-technical stakeholders.
• Collaborate cross-functionally embedding with teams like Marketing, GTM, Recruiting, or Product to identify opportunities for agent-driven automation and measurable business impact.
• Contribute to the Lang Chain and Lang Graph ecosystem, including open source components, documentation, and shared tools.

• Experienced software engineer with a strong track record shipping AI or ML-powered applications (typically 3+ years, including at least 1 year building LLM systems in production).
• Hands‑on experience implementing evaluation and monitoring systems for agents or workflows.
• Deep understanding of the components that make up an AI system: prompting, retrieval, orchestration, inference APIs, and model selection across modalities.
• Strong coding skills in Python or Type Script (ideally both).
• Excellent communicator who can simplify complex technical ideas for diverse audiences.
• Thrives in a fast‑moving, ambiguous startup environment; enjoys identifying the highest‑impact problems and driving them to completion.
• Naturally curious and motivated to learn new tools, frameworks, and approaches in applied AI.

• Expertise with Lang Chain or Lang Graph.
• Experience building or maintaining open source projects.
• Background in applied AI research or agentic workflow development.
• Based in San Francisco (preferred), NYC, or Boston.

We offer competitive compensation that includes base salary, meaningful equity, and benefits such as health and dental coverage, flexible vacation, a 401(k) plan, and life insurance. Actual compensation will vary based on role, level, and location. For team members in the EU and UK, we provide locally competitive benefits aligned with regional norms and regulations. Annual Annual Salary Range: $165,000 - $190,000

Lang Chain