Senior Software Engineer (SMTS) — Ultra Messaging

Salesforce•Chicago, IL

8d•$148,500 - $223,900•Remote

About The Position

The Senior Software Engineer SMTS role is part of the Ultra Messaging (UM) team, a small, specialized group of engineers building and maintaining one of the industry's most demanding real-time messaging middleware platforms. Ultra Messaging is mission-critical infrastructure for some of the world's largest financial institutions — including major global banks, trading firms, market makers, and exchanges — where microseconds matter and reliability is non-negotiable. The team works remotely with a preference for candidates in the Chicago area, where several team members are based. You'll be working on a mature, production-grade, system-level C codebase that has been powering real-time financial data flows since 2004. If you're a low-level systems programmer who loves performance, concurrency, and working on software that has to work right, every time — this is your role.

Requirements

5+ years of experience writing production-quality C or C++ code.
Hands-on experience with multi-threaded programming, including concurrency patterns and thread synchronization primitives.
Understanding of performance optimization at the system level — you know how to find bottlenecks and eliminate them.
Strong debugging skills and are comfortable diving deep into complex, unfamiliar codebases.
Strong written communication skills — you'll be producing requirements and design documents, and occasionally working through complex technical issues directly with customers.

Nice To Haves

Java experience, with bonus points for JNI (Java Native Interface).
Experience with networking protocols, including UDP multicast.
Low-level socket programming experience.
Experience using performance profiling tools and a methodology for systematic performance analysis.
Experience with messaging middleware — UM, Aeron, TIBCO EMS, Tibco RV, Kafka, or similar.

Responsibilities

Analyze requirements for new features, enhancements, and bug fixes; produce clear requirements documents.
Evaluate the existing codebase to determine optimal design approaches; produce design documents.
Implement changes primarily in the core C layer, with occasional work in Java (via JNI) and .NET (C#) API wrappers for cross-platform support.
Write and execute development-level tests to validate correctness and performance.
Collaborate with and support QA and customer support engineers throughout the development lifecycle.
Occasionally engage directly with customers on technically complex issues when escalation is warranted.