Site Reliability Engineering. You build the SRE practice and operate it yourself first: SLO framework, on-call rotation, and incident command process. You write the SLOs, run the rotation, lead incident response at live bank customers, and produce the postmortems. Once the practice is stable and documented, you bring in an SRE Lead to own it and grow the function.
Production Support. Before the first support hire, you define severity tiers, SLA commitments per customer tier, and escalation paths, and you route alerts into a real queue. You are the technical accountable owner when a bank has a production incident. Once the structure works, you hire into it cost-efficiently and hand off the day-to-day to a Support Lead as customer volume justifies it.
Engineering Operations. You set the operating system across all four engineering lanes: sprint discipline, release rituals, code review standards, change management evidence, and the metrics the CEO and board read monthly. You own the SOC 2 artifacts, model risk review documentation, and the change traceability that bank examiners scrutinize.