Full-Stack Platform Support Engineer (C#/.NET & React)

Topstep LLC; Northern (KY); Hybrid; USD 120,000 - 150,000; Full time

Benefits offered by this job

Company-paid holidays

Family leave

401(k) matching

Health, dental, vision insurance

Food and groceries budget

Job summary

Topstep LLC is seeking a Trading Platform Software Support Engineer to own and resolve trader-impacting issues, turning them into permanent fixes. You will write production code across C#/.NET and React, build observability surfaces, and lead end-to-end investigations across distributed services and state.

The role emphasizes an engineering-first mindset with on-call responsibilities and collaboration with cross-functional teams to prevent recurrence through tooling and platform changes.

Qualifications

• 3 to 5+ years of professional software engineering in production systems.
• Fluency in C#/.NET for back-end services and React (TypeScript preferred) for front-end work.
• Strong debugging instincts in distributed systems with end-to-end investigations.
• Foundational SQL knowledge with hands-on development experience.
• Experience with observability/logging stacks such as Datadog or Elasticsearch.

Responsibilities

• Drive escalations from reproduction to resolution, landing the right fix.
• Write production code in C#/.NET and React to resolve small-scale issues on the spot.
• Scope larger efforts into well-defined tickets for cross-team ownership.
• Build internal tooling and operator surfaces to reduce manual work.
• Lead complex investigations across distributed traces and database state.
• Reproduce trader-reported issues locally and pair with engineers when needed.
• Participate in on-call rotation and respond to active incidents.
• Coordinate with stakeholders and write post-incident reviews for learning.

Skills

C# / .NET

React (TypeScript)

SQL

Observability tooling

Debugging distributed systems

On-call / incident response

API logs / Postman

Tools

Datadog

Elasticsearch

Kibana

Postman

Job description

Topstep LLC is seeking a Trading Platform Software Support Engineer to own and resolve trader-impacting issues, turning them into permanent fixes. You will write production code across C#/.NET and React, build observability surfaces, and lead end-to-end investigations across distributed services and state.

The role emphasizes an engineering-first mindset with on-call responsibilities and collaboration with cross-functional teams to prevent recurrence through tooling and platform changes.