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Browse Open JobsFounding Engineer
Summary by AIEngineer.careers
Founding Engineer is a AI Infrastructure Engineer role (full-time). with ActiveCampaign. in LONDON, US. Imported listing (source: flexgen.zya.me). Apply on the employer's site (flexgen.zya.me).
Imported listing (source: flexgen.zya.me) · Apply on flexgen.zya.me
LONDON · US
—
Full-time
SENIOR
The sections below reproduce the third-party job description for reference. AIEngineer.careers does not write or control this text.
Imported job description
Sourced from flexgen.zya.me
Flexgen is a Seed-stage AI infrastructure startup building a high-throughput, production-grade AI gateway for the next generation of AI products. As Founding Engineer, you will design and own core backend infrastructure, work on distributed systems and Kubernetes, and collaborate directly with founders to shape technical direction. This is an on-site role in London.
Responsibilities
- Design, build, and own core backend infrastructure for a high-throughput AI gateway serving billions of tokens per day.
- Architect and evolve a pragmatic microservices system, including a core LLM gateway in Go and auxiliary ML/AI services in Python.
- Make critical decisions around distributed systems design, database selection, caching strategies, and API platform architecture.
- Profile and optimize performance for high-traffic, latency-sensitive systems with sub-20ms SLAs.
- Work hands-on with Kubernetes to deploy, manage, and scale services reliably.
- Collaborate directly with founders to translate product vision into robust, scalable engineering solutions.
Requirements
- 5+ years of experience building backend services using a compiled language, with Go (Golang) strongly preferred.
- Strong experience in distributed systems design and scalability.
ActiveCampaign
Chicago · US · 837+ employees
ActiveCampaign is an AI-first autonomous marketing and customer-experience automation platform serving businesses worldwide. Its platform supports personalized, cross-channel customer journeys and integrates automation with email, SMS, WhatsApp, CRM, sales, and more than 1,000 applications.
