Senior Software Engineer (Trade Execution)

WHO WE ARE Apex Fintech Solutions (Apex) powers innovation and the future of digital wealth management by building tech-forward solutions that help simplify, automate, and facilitate access to financial markets for all. Our robust suite of fintech software enables us to support clients such as Stash, Betterment, SoFi, Webull, and eToro, amongst many others; collectively, Apex powers access to the stock market for over 22+ million end customers.      At Apex, we are changing how the securities industry operates by reinventing the status quo, which was manual, slow, and accessible only by the ultra-wealthy. We're digitizing and democratizing systems so that everyone has an opportunity to invest.    When you're at Apex, you drive this change. You're part of a global team with a clear vision: to be the trusted technology that powers the digital economy. Our offices in Austin, Dallas, Chicago, New York, Portland, Belfast, and Manila are home to over 1,000 employees.    Together, we’re shaping the future of financial innovation. Embrace change. Solve big. Win together. And be G.R.E.A.T. — grit, results, empathy, accountability, and teamwork — with Apex.    We’re proud to be recognized for the innovative work we do, the purpose-driven nature of our work, and the collaborative culture we’ve created. Here are just a few of the many awards we’ve recently received:    Best Places to Work  2026, 2025, 2024, 2023 - Presented by BuiltIn    WealthTech of the Year  2025 - Presented by US FinTech Awards    The World’s Top 250 Fintech Companies  2024 - Presented by CNBC  ABOUT THIS ROLE Apex Fintech Solutions is looking for an experienced Senior Software Engineer with a strong focus on backend systems to join our Trade Execution team. While prior experience with C++ or C# is not mandatory, candidates must demonstrate a willingness to learn and work with these languages in the near term. This role is critical in designing, building, and maintaining scalable backend systems that power our multi-asset trading platform that US markets. This position is ideal for engineers passionate about backend development, tackling complex problems, and building systems that scale efficiently. Duties/Responsibilities Design, develop, test, deploy, maintain, peer-review, and continuously tune high-performance, high-throughput software. Collaborate with other members of the team to share, learn, develop, and deliver designs and coding standards to meet the growing needs of the platform Build resilient, self-scaling, self-healing services that deliver the highest level of reliability. Support the production systems that you design. This includes building, deploying (CI/CD), and monitoring (DataDog, Grafana, Prometheus, PagerDuty). Write commercial grade, well-tested code, and maintain high code-quality standards across your team through code reviews and other best practices. Implement instrumentation to maintain observability to proactively visualize opportunities for improvement. Education and/or Experience Bachelor’s in Computer Science, Software Engineering, or a related discipline (or equivalent work experience required) 5+ years of professional experience developing backend systems.   Strong experience with SQL databases, including query optimization, indexing, schema design, and troubleshooting.   Experience and knowledge of Linux, socket programming, concurrency and lock free data structures.  Experience integrating and developing APIs for efficient data flows.   Experience in execution management.  Experience with kernel bypass networking preferred. Experience building microservices or working with distributed systems preferred. Experience building/maintaining backend trading execution systems preferred. Exposure to Agile methodologies or iterative development practices preferred. Required Skills/Abilities Backend development expertise with proficiency in a modern programming language (e.g., C++, C#, Python, Java, Go, etc.).   Fundamental understanding of C++ and/or C# concepts, with a commitment to learning and utilizing these languages in the near term. Solid knowledge of system architecture, backend design patterns, and scalable infrastructure.   Strong debugging and troubleshooting skills for application and system-level issues.   Familiarity with version control systems (Git) and CI/CD pipelines in backend workflows.  Exceptional problem-solving and analytical thinking skills.   Strong communication and teamwork abilities, with experience collaborating across teams.   Proven track record of learning and adapting to new technologies and environments.    Work Environment This job operates in a hybrid, office environment 3 days per week. #engineering #mid-senior #full-time #LI-SD1 #APEX ​Please note this job description is not designed to cover or contain a comprehensive listing of activities, duties, or responsibilities required of the employee for this job. Duties, responsibilities, and activities may change at any time with or without notice. Our Rewards We offer a robust package of employee perks and benefits, including healthcare benefits (medical, dental and vision, EAP), competitive PTO, 401k match, parental leave, and HSA contribution match. We also provide our employees with a paid subscription to the Calm app and offer generous external learning and tuition reimbursement benefits. At AFS , we offer a hybrid work schedule for most roles that allows employees to have the flexibility of working from home and one of our primary offices. Salary Range $149,600-$187,000 The annual base salary range for this position is noted above. Exact compensation offered may vary depending on job-related knowledge, skills, experience, and office location. EEO Statement Apex Fintech Solutions is an equal opportunity employer that does not discriminate on the basis of race, color, religion, sex (including pregnancy, sexual orientation, and gender identity), national origin, age, disability, veteran status, marital status, or any other protected characteristic. Our hiring practices ensure that all qualified applicants receive fair consideration without regard to these characteristics. Disability Statement Apex Fintech Solutions is committed to creating an inclusive and accessible workplace for all candidates, including those with disabilities. We are dedicated to ensuring equal employment opportunities and providing reasonable accommodations to qualified individuals with disabilities. If you require reasonable accommodations to participate in the application or interview process, please submit your request via the Candidate Accommodation Requests Form. We will work with you to provide the necessary accommodations to ensure your full participation in our hiring process.