Senior Site Reliability Engineer, Performance Engineering

O Fallon, MO · full time · Senior

$96,000 – $163,000

Listed on Mastercard’s own careers site. You apply with them directly — we never stand between you and the employer.

What this role is

A Senior Site Reliability Engineer focused on performance testing and optimization for Mastercard's payment systems, particularly the Automatic Billing Updater service. The role suits engineers with deep expertise in distributed systems, performance bottleneck analysis, and automation who want to apply that knowledge to high-scale financial infrastructure.

Our summary, not Mastercard’s wording. The full posting is on their site.

Skills this role names

What they ask for

Required

Advanced knowledge of web applications and distributed systems infrastructure
Excellent verbal and written communication skills
Experience with performance bottleneck analysis and system design for scale
Experience with Java Virtual Machine internals and garbage collection tuning
Experience with database internals, server or operating system internals, storage system internals, or performance scaling for related platforms
Experience implementing automated performance regression test suites for low-latency, high-throughput financial applications
Experience analyzing performance bottlenecks across application code, databases, cache layers, data stores, servers, networks, messaging queues, and streaming platforms
Experience analyzing issues holistically across edge components, application tiers, and databases
Experience working directly with internal customers to resolve issues and provide performance engineering leadership
Working knowledge of AI-assisted development and analysis techniques including prompt-driven script generation and root cause analysis support

Nice to have

Bachelor's degree in Computer Science, Computer Systems, Information Technology, or related field
Experience with Java, Python, Scala, or other programming and scripting languages
Experience with Bitbucket, Maven, Jenkins, Gatling, and BlazeMeter
Experience migrating legacy on-premises testing suites to cloud-native stacks
Experience migrating performance testing suites from LoadRunner to Gatling or BlazeMeter
Strong software performance analysis, bottleneck identification, scaling, and automation experience
Experience using AI-enabled tools or large language models to generate, refactor, explain, or optimize performance testing scripts
Experience applying AI-assisted analysis to performance metrics, logs, traces, dashboards, and incident data
Familiarity with responsible AI practices including validation of AI-generated outputs and protection of sensitive data