Principal Software Engineer

Job Description

Job Description

Job Title: Principal Software Engineer

Job Description

This role focuses on working within complex, established software systems rather than greenfield development. You take ownership of challenging technical problems and drive them through to resolution, often involving integration and debugging as much as writing new code. You collaborate closely with multiple teams, influencing technical decisions and guiding direction instead of simply executing assigned tasks. The position emphasizes robust engineering practices, code quality, application security, and reliable system integration in demanding, mission-critical environments.

Responsibilities

• Work extensively within existing, complex embedded and systems software, enhancing functionality, improving reliability, and addressing defects.
• Take end-to-end ownership of technical problems, from initial investigation and root cause analysis through to implementation, testing, and deployment of solutions.
• Lead integration efforts between software components and systems, ensuring seamless communication, compatibility, and performance across interfaces.
• Perform detailed debugging and troubleshooting of embedded C and systems integration software, identifying and resolving issues in a methodical and timely manner.
• Provide technical leadership across projects, guiding design decisions, setting engineering standards, and mentoring other engineers on best practices.
• Apply full software development lifecycle (SDLC) practices, including version control, build management, testing, and deployment processes.
• Use static code analysis tools and other code quality initiatives to maintain high standards of reliability, maintainability, and security.
• Incorporate secure coding practices and application security principles into design, implementation, and code reviews.
• Collaborate with cross-functional teams to align on architecture, integration strategies, and technical solutions, influencing decisions through clear communication and technical expertise.
• Work with networking and system communication concepts to design, integrate, and troubleshoot communication between components and systems.
• Document technical designs, integration approaches, and troubleshooting findings to support maintainability and knowledge sharing.
• Continuously improve existing systems and processes by identifying technical debt, proposing enhancements, and implementing robust solutions.

Essential Skills

• Strong proficiency in embedded C development, particularly within complex, existing systems.
• Proven experience with systems integration software, including integrating multiple components and services.
• Demonstrated technical leadership, with the ability to guide architecture, influence decisions, and mentor other engineers.
• Hands-on experience with full SDLC practices, including version control, build systems, testing, and deployment processes.
• Practical experience using static code analysis tools and driving code quality initiatives.
• Familiarity with secure coding practices and application security principles.
• Exposure to networking or system communication concepts and their application in integrated systems.
• Experience working on defense or mission-critical systems, or similarly high-reliability environments.
• Strong debugging and problem-solving skills, especially in complex, integrated software environments.
• Ability to work effectively across teams, communicate clearly, and influence technical decisions.

Additional Skills & Qualifications

• Experience implementing and improving code quality processes across large or complex codebases.
• Prior involvement in projects with strict reliability, safety, or security requirements.
• Experience collaborating with multidisciplinary teams such as hardware, systems, or test engineering.
• Familiarity with industry-standard tools for version control, continuous integration, and automated testing.
• Ability to document designs, integration strategies, and troubleshooting steps in a clear and structured manner.
• Comfort working in environments where priorities can shift and where legacy systems must be maintained and enhanced.

Work Environment

You work primarily with embedded C and systems integration software in a mature, complex codebase rather than in greenfield projects. The environment emphasizes disciplined SDLC practices, including structured version control, build pipelines, testing, and controlled deployments. You regularly use static code analysis tools and other quality-focused technologies to maintain high standards of reliability and security. Collaboration is central to the role, with frequent interaction across multiple teams and disciplines to align on integration, architecture, and technical decisions. The work centers on mission-critical or high-reliability systems, requiring careful attention to detail, robust debugging, and strong adherence to secure coding and application security practices.

This is a Contract position based out of Bridgeton, MO.

The pay range for this position is $65.00 - $68.00/hr.

Eligibility requirements apply to some benefits and may depend on your job classification and length of employment. Benefits are subject to change and may be subject to specific elections, plan, or program terms. If eligible, the benefits available for this temporary role may include the following:
• Medical, dental & vision
• Critical Illness, Accident, and Hospital
• 401(k) Retirement Plan – Pre-tax and Roth post-tax contributions available
• Life Insurance (Voluntary Life & AD&D for the employee and dependents)
• Short and long-term disability
• Health Spending Account (HSA)
• Transportation benefits
• Employee Assistance Program
• Time Off/Leave (PTO, Vacation or Sick Leave)

This is a hybrid position in Bridgeton,MO.

This position is anticipated to close on Jul 21, 2026.

About Actalent

Actalent is a global leader in engineering and sciences services and talent solutions. We help visionary companies advance their engineering and science initiatives through access to specialized experts who drive scale, innovation and speed to market. With a network of almost 20,000 consultants and 5,000 clients across the U.S., Canada, Asia and Europe, Actalent serves many of the Fortune 500. We are proud to be an Engineering News-Record (ENR) Top 500 Design Firm for our engineering design services and a ClearlyRated Best of Staffing® winner for both client and talent service.

The company is an equal opportunity employer and will consider all applications without regard to race, sex, age, color, religion, national origin, veteran status, disability, sexual orientation, gender identity, genetic information or any characteristic protected by law.

If you would like to request a reasonable accommodation, such as the modification or adjustment of the job application process or interviewing process due to a disability, please email View email address on ziprecruiter.com for other accommodation options.

San Francisco Fair Chance Ordinance: Pursuant to the San Francisco Fair Chance Ordinance, for all positions located in the city and county of San Francisco, we will consider for employment qualified applicants with arrest and conviction records.

Massachusetts Lie Detector: It is unlawful in Massachusetts to require or administer a lie detector test as a condition of employment or continued employment. An employer who violates this law shall be subject to criminal penalties and civil liability.

Use of Artificial Intelligence (AI): We may use Artificial Intelligence (AI) to support parts of our hiring process, including sourcing, screening, and evaluating candidates. AI helps assess applications and qualifications, but final decisions are made by our hiring team. By applying, you acknowledge and agree that your application may be reviewed using AI tools.