Software Test Engineer III; Contractor

About Sierra Space

At Sierra Space, we build the missions and systems that keep our world secure in the domain above Earth. Sierra Space team members share a spirit of innovation and collaboration and a belief that we can deliver on the boldest missions in space today. Together with our customers, we aim to safeguard our nation, sustain human presence in space, and secure the freedom of operations in low Earth orbit and beyond.

Our success is measured by the trust of those who rely on what we build and deliver, and our technologies keep the United States and its allies mission‑ready throughout space. We are mission‑driven, and together, we are an extraordinary team.

The Software Test Engineer III is responsible for leading testing processes, designing comprehensive test plans, developing testing strategies, and architecting testing frameworks for large and complex aerospace software projects. You will participate in the development and execution of comprehensive test plans, test cases, and test procedures to verify the functionality, performance, and reliability of aerospace software systems used in space vehicles and other aerospace applications.

In this role you will also be responsible for coordinating testing activities, ensuring thorough coverage of all requirements, and performing defect triage. Your role will involve significant interaction with cross‑functional teams, including software development, systems engineering, and quality assurance to ensure compliance with technical specifications and adherence to software quality standards. You will also mentor and guide junior engineers, fostering a culture of continuous improvement and technical excellence while contributing to the success of complex space missions.

In this role, you will assist in leading the development and execution of comprehensive test plans, test cases, and test procedures to ensure the functionality, performance, and reliability of software systems. You will lead the development and review of automated test scripts to be leveraged in a Continuous Integration environment, collaborating with software developers and other engineers to understand software requirements and design effective test strategies.

You will prioritize and plan testing activities in a fast‑paced environment, oversee the defect lifecycle from discovery to resolution by working with developers to reproduce issues and verify fixes, and support the definition of software test risks and opportunities while considering cost and schedule impacts. Additionally, you will review and analyze software design descriptions, ICDs, and requirements in coordination with software development teams, lead and contribute to the continuous improvement of testing processes and methodologies, and implement automated testing tools and frameworks to optimize testing and verification processes.

Reporting bugs and errors to development teams and providing insightful feedback to assist in decision‑making will be key, as will performing regression testing to ensure new software updates do not negatively impact existing functionality or performance. You will utilize automated testing tools and frameworks to enhance testing efficiency and coverage, maintain and update test documentation such as test plans, test cases, and test reports, and participate in code reviews to provide feedback on software quality and testability.

Staying current with industry best practices and emerging technologies in software testing will be an essential part of your role, along with mentoring and guiding junior test engineers by providing technical support and knowledge sharing. Finally, you will design and architect complex software test systems to meet project requirements.

Our mission is driven by an unyielding commitment to advancing space‑based technology in service of our customers and safeguarding national security. We seek individuals who are passionate about innovating beyond boundaries and relentlessly pursuing solutions that protect, preserve and empower – to join us in this critical mission. We’re looking for team members who align with our values, mission and…