Company profile

Group One Trading Tech Stack

Proprietary market maker in US equity options built on in-house software

Financial Services Chicago, Illinois 51–200 employees Founded 1989 Partnership

Group One Trading is a Chicago proprietary trading firm making markets in US equity options, running a Microsoft-centric stack of C#, .NET, SQL Server and Azure alongside C++ and Python with Pandas and Polars for quantitative work. Accelerating, engineering-led hiring weighted toward interns and juniors points to building a developer pipeline, while job posts stress trading system uptime and incident handling.

Tech Stack 17 technologies

Core StackC# C++ Python Jira .NET Java SQL Server Pandas Objective-C Windows 10 Windows 11 Azure Exchange Online VMware vSphere Entra Polars VBA

What Group One Trading Is BuildingChallenges and projects from their job posts

◆Challenges

Improving trade quality, volume and profitability
Maintaining trading system uptime and managing incidents
Delivering complex technology initiatives

▲Active Projects

Improving proprietary trading systems
Translating research into trading decisions
System monitoring and incident response

Hiring Activity

Accelerating10 roles · 9 in 30d

Department

Engineering

Finance

Ops

Research

Support

Seniority

Intern

Junior

Mid

Senior

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About Group One Trading

Group One Trading is a proprietary trading firm headquartered in Chicago, Illinois, founded in 1989 and organized as a partnership. The firm acts as a market maker in US equity options, trading its own capital rather than serving outside clients. Its edge rests on risk management combined with internally developed trading software. The company employs between 51 and 200 people and hires in the United States across engineering, finance, operations, research and support.

HeadquartersChicago, Illinois

Company Size51–200 employees

Founded1989

Hiring MarketsUnited States

Frequently Asked Questions

What tech stack does Group One Trading use?

Group One Trading uses C#, C++, Python, Java and .NET, with SQL Server, Azure, VMware vSphere and Entra for infrastructure, Pandas and Polars for data work, and Jira for project tracking.

Is Group One Trading hiring software engineers?

Yes. Hiring is accelerating and led by engineering, with additional openings in finance, operations, research and support, and a strong emphasis on intern and junior positions in the United States.

Where is Group One Trading headquartered?

Group One Trading is headquartered in Chicago, Illinois. Founded in 1989, it is a partnership with 51 to 200 employees focused on US equity options market making.

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How this profile is built

Group One Trading's technology stack, projects, and hiring signals are inferred from public hiring and company data — career pages, public listings, and company web presence — then clustered and de-duplicated. Figures are estimates that refresh over time. Read our full methodology →

This is not an official vendor or customer list. It is a technology-adoption signal inferred from public data, intended for B2B research.