Deployed Engineer
Build AI agents with LangChain’s customers and put them into production.
- London
- Full time
- Writing example code
- Pay not listed
This job is open.
Jack’s take. Jack is an AI agent who gets to know what you’re great at, then finds your next job and helps you land it.
“This is a builder’s job. You’d own the technical win before the customer buys, and stay afterward to advise.”
Who it suits
A good fit if you
- You want to build agents with the customer’s own engineers.
- You can explain tradeoffs to a room of developers.
- You want responsibility for the customer’s outcome.
Think twice if you
- You want to stop once the demo works.
- You haven’t designed an agent past a simple API call.
- You prefer to stay out of pre-sales conversations.
What you’d do
- Co-design and co-build production AI agents with the customer’s engineers.
- Design proofs of concept, answer hard technical questions, and guide evaluations while the customer is still deciding.
- Help customers deploy and operate agents, including conversational agents, research agents, and multi-step workflows.
- Run demos, trainings, and workshops for developers, and turn field lessons into patterns other customers can reuse.
What they ask for
- You have 3 or more years in a technical role, ideally at a startup or a growing company. That includes software engineering, customer engineering, solutions engineering, or a founding engineer role.
- You have strong Python and JavaScript, and solid systems fundamentals.
- You’ve designed agent or LLM applications past a simple API call, including multi-step workflows, orchestration, and failure handling.
- You’re comfortable with customers during proofs of concept, architecture reviews, and technical evaluations. You take responsibility for the outcome.
How it works
- They use the interviews to understand your impact, craft, leadership, and communication. They tell you where you stand before they make an offer.
What to know before you apply
Open at least 13 weeks, longer than most London FDE roles
- Week 11Half of London FDE roles have closed
- Week 13This job so far
In November 2026, LangChain had 13 deployed engineer jobs open in 11 locations.
The builder, the most common kind of FDE in London
- 62%The builder (this job). Writes production code inside the customer’s stack: integrations, data pipelines and AI applications.
- 34%The deployment lead. Scopes and runs the rollout, turns the customer’s problem into a working solution and owns the outcome.
Shares of open FDE roles in London.
Most new London FDEs weren’t FDEs before
- 93% of people who became FDEs in London weren’t FDEs in their last job.
- 54% came from a startup or scale-up.
LangChain doesn’t list pay for this job
Our London FDE guide shows what FDEs in London expect to earn, so you can talk numbers with confidence.
What London FDEs earnWorth asking the hiring team
- “These openings don’t all have the same scope. What should the person in London expect?”
- “How do you want a week split between the evaluation before a sale and the advice after deployment?”
Jack’s take on LangChain
- Its COO says it has beaten its plan 11 quarters running
- Valuation rose from $200M to $1.25B in 20 months
- The team grew from about 150 to about 400 people this year
- Based in San Francisco, New York and Boston
- Founded 2023
- 100 open roles
Similar jobs in London
The same kind of job at other in-demand startups.
About this page
Jack & Jill isn’t LangChain’s recruiter. We summarized this job from LangChain’s public careers page, where you can apply, and we check whether it’s still open each time you open this page. The market numbers come from our London FDE guide and the company facts from LangChain’s company page. We last checked this summary against the posting on November 9, 2026. Jack’s take is Jack & Jill’s own.