Senior Back End Engineer

Zello•Austin, TX

21h

About The Position

This role is on Zello's backend services team, which owns and operates the distributed systems carrying every conversation our customers depend on. You'll join as the third engineer on a high-ownership team, taking full production responsibility for our most critical services from day one. There are no layers of management between you and the work that matters. After a successful first year, you will have owned full production responsibility for at least one critical existing service (on-call, SLOs, incident response) and measurably improved its reliability. You will have extended observability coverage with Grafana and Loki dashboards and alerting, shifting the team's posture from reactive to proactive. You will have shipped at least three non-trivial reliability, performance, or architecture improvements into production. You will have contributed a meaningful component to backend 2.0, which is a ground-up rearchitecture toward an AI-native engineering posture.

Requirements

Carried real production weight on distributed systems at scale, and you talk about reliability as something you own, not something you measure.
Shipped C++ in production for years and read long-lived backend codebases without flinching.
Gone deep on at least one of Cassandra, MongoDB, or MySQL, and can name the tradeoffs because you've felt them in production.
Use AI-assisted development as a default and have shaped CLAUDE.md, AGENTS.md, .cursor/rules, or equivalent for a real team.
Thrive on a small team where every hire moves the needle. You drop ego in code review. You take scope, you don't wait for it.
Your definition of "done" includes tests, alerts, observability, and runbooks.

Nice To Haves

Rust or Go in your toolkit is a plus.

Responsibilities

Operate as a senior individual contributor on the backend services team, owning production for distributed systems at real-time scale.
Carry the on-call rotation for Zello's most critical infrastructure. Lead incident response, write runbooks, and turn each incident into a durable improvement.
Build observability where it's missing. Set SLOs, instrument services with Grafana and Loki, and shift team posture from reactive to proactive.
Ship production C++ today; contribute to Rust and Go components as they come online.
Work hands-on across our database stack: Cassandra, MongoDB, MySQL and choosing the right tool for the workload.
Contribute to backend 2.0: a ground-up modernization of the platform anchored on AI-native engineering workflows.