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# Senior C#/Java Engineer - Order Flow & Trading Services

- **Company:** Liberty Personnel Services, Inc.
- **Location:** Philadelphia, PA, United States (Remote available)
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** Java (Programming Language), .NET Framework, C Sharp (Programming Language), Software Engineering, Multithreading, Build Management
- **Published:** October 15, 2026
- **Apply:** http://www.libertyjobs.com/findjobs-details.php?j_id=90099

## About the Role

6-12+ years of professional software development

 - Strong C#/.NET and/or Java

 - Experience building high-performance, multithreaded back-end services

 - Plus: trading, order routing, FIX or market-data background

 - Two openings

Work model: On-site 5 days/week (Philadelphia Main Line suburb), with an annual WFH day bank.

Type: Full-time, direct hire. Salary: open, plus bonus.

## Description

A leading proprietary trading firm is adding two senior engineers to the performance-focused services layer that every order passes through, between its trading front ends and core systems. If you care about latency, throughput and clean design, this is the team.

What you'll do

 - Design and build order-flow and trading-path services in C#/.NET and Java