Member of Technical Staff (MTS) – Core Full-Stack / Backend
Fi Money
About UsWe are an AI-first engineering intelligence platform building the future of developer workflows completely from scratch. We are the core engineering team behind Fi, where we built and scaled fintech systems for over 3 million users. We don’t stitch together basic API wrappers; we work directly on deep system architectures. If you want a highly challenging, completely flat environment where you own your vertical without bureaucratic red tape, this is it.
The Role & Technical DepthWe are shifting past static components into high-concurrency, data-heavy production web flows and fully autonomous AI agent systems. We need a stellar engineer who can write high-performance backends and wrap deterministic, bulletproof software around non-deterministic AI outputs.
Build the Stack: Design, develop, and optimize core services, heavy web architectures, and transaction flows for our platform.
Production-Grade AI Agents: Take AI loops out of the "toy project" phase and build the software loops, validation guardrails, and caching mechanisms required to run them reliably at scale.
Performance Engineering: Diagnose and resolve complex backend bottlenecks, database deadlocks, and high-concurrency latency spikes.
Our Expected Stack: Go (Golang) or high-performance backend equivalents, relational/non-relational databases, Redis cache/queuing systems, and modern, highly optimized web engineering frameworks.
Who You AreExperience: 3–4 years of intensive full-stack or backend engineering experience.Startup DNA: Proven track record in high-velocity tech startups with heavy execution demands. You excel in ambiguous environments where the destination is clear but the map is yet to be drawn.Strong Fundamentals: You know how to build software that scales. You understand memory management, concurrency primitives, asynchronous task processing, and how web protocols actually break under load.
Create your free OnJob profile to apply — we'll take you to Fi Money's application after sign-up. · Posted 19 May 2026.
Related Engineering jobs
Hand-picked roles that match this listing on skills, category and location — each scored to your profile inside OnJob.
Explore more on OnJob
Hiring for a role like this?
Post a job on OnJob and reach AI-matched candidates.