Customer Engineer, Agent Builder

London, UK · On-site · Full-time
Compensation: £110,000–£150,000 + competitive equity

About the Company

A category-leading conversational AI platform (Series D+, 201–500 people) that helps major enterprise brands deploy AI agents across voice, chat, email, SMS, and every other channel — replacing support tickets and hold music with faster resolutions and richer conversations. Backed by top-tier venture investors and trusted by recognized enterprise brands.

Founded 2023 · 201–500 people · Industry: Conversational AI / Customer Support

The Role

A post-sales, deployed engineering role that owns end-to-end execution of AI agent builds for strategic enterprise customers. It’s a highly technical delivery role, split roughly 50/50 (up to 60/40) between hands-on technical build and customer-facing engagement, inside a newly formed Agent Builder team working in tight feedback loops with product, success, engineering, and go-to-market. Travel is rare.

What you'll be doing

• Own end-to-end architecture and execution of AI agent builds for enterprise customers — systems design and scoping through implementation, evaluation, and production deployment.
• Design and engineer the core agentic logic governing agent behavior, plus layered guardrails and supervisory controls for safe, compliant, predictable performance across non-deterministic outputs.
• Architect, build, and test integrations with customer systems (data pipelines, CRMs, ticketing systems) — the tools, APIs, and workflows needed for reliable deployment at scale.
• Interface with senior technical stakeholders at customers to define success criteria and system requirements, and drive technical delivery against timelines.
• Diagnose, debug, and resolve probabilistic and technical failures via root-cause analysis, and design evaluation and regression-testing frameworks that guard against performance drift.

Tech stack: Python (core); LLM / AI-agent tooling (prompting, evaluation, guardrails, workflow design); enterprise integrations (CRMs, ticketing systems, data pipelines, APIs).

Requirements

• 3 to 5 years technical customer-facing experience, post-sales
• Strong Python proficiency (hard requirement)
• CS or adjacent quantitative degree preferred
• LLM / AI agent build experience a plus

Green Flags

• Software engineer or forward-deployed engineer pivoting intentionally into customer-facing, post-sales delivery
• Strong, demonstrable Python ability with end-to-end integration work, comfortable coding without AI assistants
• Track record of delivering production-grade customer solutions requiring structured execution, testing, and iteration
• Clear communicator who can be walked into a room with senior executives without hand-holding
• CS degree from a strong program and hands-on experience building with LLMs or AI agents (prompting, evaluation, guardrails, tooling)

Red Flags

• Wants to pivot toward pre-sales rather than own post-sales technical delivery
• Weak or unproven Python, or reliance on AI coding assistants to produce working code
• Purely operational or IT-management background that does not transfer to hands-on engineering

Why Join

• Ground-floor seat on a newly formed Agent Builder team (small and growing) with real influence over how the team and the agent-building platform evolve.
• Genuine technical depth — hands-on build work (agentic logic, guardrails, integrations, evaluation frameworks) alongside customer-facing delivery, not a pure customer-success seat.
• Category-leading platform with strong venture backing and marquee enterprise customers.

Details

• Location — London, UK
• Work policy — In-office, 5 days per week
• Compensation — £110,000–£150,000 + competitive equity
• Visa sponsorship — None available
• Employment type — Full-time