Senior SDET – Trading Systems | C#/.NET | Python | Backend/API Testing

Introduction

QuellSoft is seeking an experienced Senior Software Development Engineer in Test (SDET) to support a large-scale Equity Derivatives Trading Platform within a leading investment banking environment.

This is not a generic UI automation role. The ideal candidate will have strong hands-on experience across backend, API, database, integration, and UI automation, with the ability to validate complex trading workflows end-to-end.

The candidate should have strong experience with C#/.NET, Python, SQL Server, REST APIs and backend/service testing, along with hands-on experience with TestComplete or a comparable automation framework.

Strong Capital Markets / Trading domain knowledge, particularly Equity Derivatives, Options, Futures, Swaps and trade lifecycle, is highly important for this position.

Key Responsibilities

• Design, develop and maintain scalable SDET automation frameworks.
• Develop automated tests for backend services, APIs, databases, integrations and UI workflows.
• Validate end-to-end trading workflows across multiple application and service layers.
• Perform backend and database validation using SQL Server.
• Develop API and service-level automation using REST and related technologies.
• Automate Windows-based applications and services using TestComplete or equivalent tools.
• Analyze application behavior and, where required, application code to identify effective automation entry points.
• Validate data flow between UI, services, messaging systems and databases.
• Develop automated regression, integration and end-to-end test suites.
• Create test data and utilities required for complex trading scenarios.
• Investigate failures by analyzing application logs, API responses, database records and service behavior.
• Integrate automated tests with Jenkins/Bamboo and CI/CD pipelines.
• Collaborate closely with developers, QA engineers, business analysts and DevOps teams.
• Participate in code reviews and contribute to improving automation quality and coverage.
• Support release validation and continuous testing.

Required Skills

SDET / Automation

• 5+ years of hands-on SDET / QA Automation experience.
• Strong experience developing automation frameworks rather than only executing existing scripts.
• Strong programming experience in C#/.NET.
• Strong Python scripting/automation experience.
• Experience with TestComplete is strongly preferred.
• Experience with Selenium, Ranorex, UFT or similar automation tools is beneficial.

Backend / API / Database Testing

Strong backend testing experience is required.

• Experience testing backend services and distributed applications.
• Strong experience with REST API testing and automation.
• Experience with Postman, RestSharp, REST Assured, Newman or similar tools.
• Strong SQL Server experience.
• Ability to write SQL queries for:
  • Data validation
  • Transaction validation
  • Test data preparation
  • Reconciliation
  • Backend assertions
• Experience validating data across UI → API/service → database.
• Experience with integration and end-to-end testing.
• Experience troubleshooting failures across application, service and database layers.

Trading / Capital Markets

Capital Markets experience is highly preferred and will be a major factor in candidate selection.

• Experience working with Capital Markets / Investment Banking / Trading Systems.
• Strong understanding of Equity Derivatives.
• Knowledge of one or more of:
  • Options
  • Futures
  • Swaps
  • Bonds
• Understanding of the end-to-end trade lifecycle, including:
  • Order creation
  • Execution
  • Allocation
  • Enrichment
  • Booking
  • Confirmation
  • Settlement
• Experience testing Order Management / Trading platforms.
• FIX Protocol experience is strongly preferred.

CI/CD & Engineering

• Jenkins, Bamboo or equivalent CI/CD tools.
• Git / Bitbucket.
• Experience integrating automated tests into CI/CD pipelines.
• Windows Services and/or IIS applications.
• PowerShell and/or scripting for