Senior Full Stack Engineer - AI Harness

The role / impact This senior engineering position owns a critical delivery stream on MyXero, the foundational platform that underpins every organisation and user record while managing hundreds of millions of daily requests. You will take ambiguous platform challenges from problem framing to durable architectural solutions, designing the specs, verification harnesses, and AI guardrails that enable software agents to handle implementation safely. Your work directly enables the modernisation of a massive system into decoupled domain services without disrupting dependent products. By engineering automated verification loops and robust testing harnesses, you will ensure high reliability, mentor team members, and shape how our engineering practices operate safely with intelligent tools. The team / how they connect You will join the MyXero Ghostbusters squad within our Identity and Platform group, collaborating with engineers and product partners primarily based across New Zealand. The team operates with a written-first, remote-first philosophy, using design records, paired kick-offs, and blameless reviews to ensure every voice is heard and no one works in isolation. While delivery is hi... Click Apply to read the full job description.