Senior Backend Engineer
London (Hybrid)
Early-Stage | AI Platform | Enterprise-Grade Systems
We're partnering with an ambitious early-stage AI company building a challenge-based interview intelligence platform. The product replaces CV-noise with real signal — evidence from real work and real human capability.
They're in full build mode toward launch. Small team. High standards. High ownership. No corporate theatre.
They're hiring a Senior Backend Engineer to build the enterprise backbone of the platform — high-concurrency APIs, event-driven systems, and reliability foundations that transform complex hiring inputs into secure, trusted, GDPR-safe outputs.
If you enjoy turning evolving product intent into production-grade systems that don't flinch under load, this role will suit you.
What You'll Own
Enterprise-Grade Architecture
Standardised patterns from intake → build → QA → deploy → measure
Secure-by-default engineering
GDPR-safe, compliance-ready systems
Workflow Automation at Scale
Scalable GraphQL APIs
Event-driven systems with strong reliability guarantees
Monitoring, logging, error handling & documentation that scales
What You'll Build
High-concurrency APIs with retries, idempotency, and queue-based reliability
Cloud-native architecture across GCP (with limited AWS usage for asset management)
Reporting and dashboard surfaces that remain consistent under load
Systems designed to scale confidently from 10 → 10,000+ users
Tech Stack
NodeJS
GraphQL (NestJS)
PostgreSQL
Prisma
GCP
Terraform
AI / LLM integrations (including Gemini)
What They're Looking For
Strong fundamentals: data structures, OOP, and complexity analysis
Experience building high-concurrency, event-driven systems
Reliability mindset (monitoring, logging, QA, incident-aware design)
Experience integrating AI/LLMs
Comfortable working in sprints with evolving requirements
Strong analytical and problem-solving ability