Senior AI Engineer (Backend)

Join us in building Freeflo—an AI-powered booking and payment agent that works inside WhatsApp.

I’m looking for a senior, hands-on engineer to work closely with me, the founder, to build the product and shape its technical direction from an early stage.

This is primarily a product and backend engineering role. You’ll write production code, make pragmatic architecture decisions, and help turn conversational AI capabilities into reliable booking and payment experiences.

You should be comfortable moving quickly while maintaining good engineering standards. You’ll also help establish effective workflows around Codex, AI-assisted development, testing, and delivery.

What you’ll do

• Build and improve Freeflo’s Python backend
• Design and operate AWS Lambda and serverless infrastructure
• Integrate LLMs and external AI services into production workflows
• Build WhatsApp-based booking, payment, and customer-service flows
• Design APIs, data models, webhooks, and asynchronous processes
• Improve testing, monitoring, observability, security, and deployment
• Diagnose production problems and improve system reliability
• Make pragmatic architecture decisions for an evolving early-stage product
• Pair with the founder on implementation, product decisions, and technical trade-offs
• Establish efficient Codex and AI-assisted development workflows

Required experience

• Strong professional Python experience
• Experience building and operating production backend systems
• Experience with AWS Lambda or comparable serverless infrastructure
• Practical experience integrating LLMs or AI APIs into real products
• Experience designing APIs and event-driven or asynchronous workflows
• Good understanding of databases, testing, deployment, and observability
• Ability to make sound architecture decisions without over-engineering
• Ability to explain technical choices and trade-offs clearly
• Comfortable working hands-on in an early-stage, fast-changing environment

Nice to have

• WhatsApp Business Platform or Meta API experience
• Stripe or other payment-platform experience
• Booking, scheduling, messaging, or conversational-system experience
• AWS infrastructure-as-code experience
• Experience with queues, webhooks, retries, and idempotent processing
• Experience mentoring, pair programming, or working closely with founders
• Experience using Codex or similar AI development tools effectively

The right fit

You’re a senior engineer who still enjoys writing and shipping code.

You can take an ambiguous product requirement, clarify it, design a sensible solution, and carry it through to production. You balance speed with reliability and make architecture decisions appropriate for the product’s current stage.

You’re collaborative, communicate clearly, and are comfortable building alongside the founder rather than working in isolation.