Software Engineer jobs in Missouri

Cigna

Full-time · Saint Louis, MO

This role involves managing and supporting Hyperion Enterprise Performance Management systems at a large healthcare company, including platform operations, financial reporting, and system optimization. It suits someone with software development background who wants to specialize in financial planning and consolidation systems within a hybrid work setup.

Listed on Cigna’s careers site · Apply there ↗

Mastercard

Full-time · O Fallon, MO · $115,000 – $184,000

This role involves building enterprise applications using Java and modern front-end frameworks within Mastercard's payments technology division. It suits experienced full-stack developers comfortable with cloud architectures, database design, and cross-functional collaboration on complex financial systems.

Listed on Mastercard’s careers site · Apply there ↗

LSEG

Saint Louis, MO

A mid-level software engineering role focused on building and maintaining real-time news distribution systems using C++ and cloud technologies. Suited for engineers comfortable with low-level systems programming who want to work on high-performance infrastructure delivering news globally.

Listed on LSEG’s careers site · Apply there ↗

Boeing

Full-time · Hazelwood, MO · $135,000 – $165,000

This role develops and maintains software systems for Navy missile programs, applying model-based systems engineering and working across the full software lifecycle from requirements through testing and deployment. It suits engineers with defense contracting experience who can manage complex DoD projects and collaborate within established process frameworks.

Listed on Boeing’s careers site · Apply there ↗

LSEG

Saint Louis, MO

This role involves building and maintaining high-performance, low-latency financial data processing systems in C++ on Linux, where you'll work alongside experienced engineers on real-time market infrastructure that serves global exchanges. It suits mid-career developers with strong C++ fundamentals who are ready to deepen their systems programming expertise while contributing to mission-critical financial technology.

Listed on LSEG’s careers site · Apply there ↗

Mastercard

Full-time · O Fallon, MO · $122,000 – $207,000

This role leads the design and evolution of Mastercard's Workday enterprise platform, focusing on integrations, modern application development, and employee experience at global scale. It suits senior engineers with deep Workday expertise who can architect solutions, mentor teams, and drive platform modernization through emerging technologies.

Listed on Mastercard’s careers site · Apply there ↗

LSEG

Saint Louis, MO

Lead the observability strategy and hands-on implementation for real-time market data systems, working across multiple engineering teams to embed monitoring practices and optimize customer experience. This role suits experienced engineers who combine strong C++ skills with observability expertise and can guide teams on building measurable, reliable systems.

Listed on LSEG’s careers site · Apply there ↗

Mastercard

Full-time · O Fallon, MO · $140,000 – $231,000

Lead a critical team building the payment authorization system that processes billions of transactions globally, designing scalable solutions and mentoring engineers. Ideal for experienced C/C++ developers who thrive on complex performance challenges and want to shape technical direction in a secure, high-reliability environment.

Listed on Mastercard’s careers site · Apply there ↗

LSEG

Saint Louis, MO

This role involves building and maintaining internal development tools for a major financial infrastructure company, working across multiple technology stacks to support other engineering teams. It suits experienced engineers who enjoy solving infrastructure problems, collaborating across organizational boundaries, and want to deepen their knowledge of financial systems.

Listed on LSEG’s careers site · Apply there ↗

LSEG

Saint Louis, MO

LSEG Data & Analytics is hiring software engineers to build enterprise financial data and analytics platforms, with opportunities to work on AI-powered solutions serving global markets. This role suits engineers with solid experience in major languages who are curious about emerging technologies and want to tackle complex problems at scale in financial infrastructure.

Listed on LSEG’s careers site · Apply there ↗

LSEG

Saint Louis, MO

A senior-level software engineer role focused on building internal development tools and utilities for a major financial markets infrastructure company. The position suits experienced engineers who enjoy working across multiple technology stacks, collaborating with internal teams, and helping advance DevOps practices in a complex, regulated environment.

Listed on LSEG’s careers site · Apply there ↗