Senior AI Agentic Software Engineer

Company: A-Players
Apply for the Senior AI Agentic Software Engineer
Location: Greater London
Job Description:

* This is a remote first opportunity for EU-based candidates

A-Players is helping Poolday hire a Senior Agentic Software Engineer to build the core agent systems behind a next-generation AI-powered video editor. Poolday is creating a new category of creative tooling that combines a traditional timeline-based editor with autonomous AI agents that can understand intent, generate visuals, and manipulate projects end-to-end.

This role will work closely with the founders and early engineering team to design and implement the agentic architecture that powers the product. This is a high-ownership position with significant influence over system design, product direction, and engineering culture.

About Poolday

Poolday is building a modern video editor where users describe what they want, and intelligent agents assemble compositions, generate pixels, and perform edits autonomously. The product blends familiar creative workflows with cutting-edge agentic AI systems.

The founding team consists of experienced operators and builders with a strong track record of shipping complex products. Poolday is early-stage, product-driven, and focused on building category-defining creative tools.

What You’ll Be Doing

  • Designing and building multi-agent systems in TypeScript, including a primary orchestration agent and specialized sub-agents
  • Architecting agent workflows that interpret user intent, plan multi-step edits, and execute them across a video timeline
  • Building the interface layer between agents and the video editor, enabling agents to read project state, issue commands, and observe results in real time
  • Developing agent capabilities for scene composition, visual generation, timing adjustments, effects, and compositing
  • Implementing plan-and-execute loops, recovery strategies, and feedback mechanisms for reliable autonomous editing
  • Creating memory and context systems that allow agents to reason about project state, user preferences, and editing history
  • Working closely with founders to shape both the product vision and the technical foundations of the platform

What Poolday Is Looking For

Must-Have

  • 5+ years of professional software engineering experience with strong system design skills
  • Deep expertise in TypeScript, including building large, maintainable codebases
  • Experience building complex front-end or editor-like applications using React
  • Hands-on experience with agentic systems (e.g. LangChain.js, LangGraph.js, Vercel AI SDK, or custom agent frameworks)
  • Strong understanding of agent orchestration patterns such as hierarchical delegation, multi-agent collaboration, and plan-and-execute loops
  • Experience designing APIs or command layers to programmatically control complex applications
  • Strong prompt engineering skills, including function calling and structured outputs
  • Ability to work independently in ambiguous, fast-moving environments

Nice to Have

  • Experience with video editing software, motion graphics, or creative tooling
  • Familiarity with generative Al for images or video
  • Experience building plugin systems or extensible application architectures

Why Join Poolday

This is a chance to help define how AI agents will power creative tools. You’ll work on a product where users describe an idea and watch agents build it – composing scenes, generating visuals, and assembling edits autonomously.

Poolday offers real ownership, deep technical challenges, and the opportunity to shape a product from early traction to scale.

#J-18808-Ljbffr…

Posted: March 27th, 2026