
Custom Software Engineering that Balances Cost, Quality & Schedule Without Compromise. Get to Know PSI.
At PSI Software, we don’t just write code—we engineer confidence. For over 40 years, we have been dedicated to developing mission- and safety-critical software solutions that power highly regulated industries, ensuring security, compliance, and long-term performance. From medical devices and industrial automation to government and defense systems, our full-stack development process is built on deep technical expertise, a consultative approach, and an unwavering commitment to quality.
Your custom software needs to meet the highest standards—without delays, security risks, or costly rework. That’s why we don’t take shortcuts. We develop every system with precision, aligning our process with your goals to ensure compliance, longevity, and seamless integration. We are a 100% US-based team providing the highest levels of cybersecurity and possessing a number of crucial ISO certifications to meet the strictest industry regulations.

PSI's Visionary Founding: Built on Expertise & a Relentless Commitment to Quality
In 1979, Walter and Susan Johnson founded Precision Systems, Inc. (PSI) with a shared vision: to engineer the highest quality embedded real-time software systems for industries where failure is not an option. Walt’s extensive experience in leading complex software projects provided the technical backbone. At the same time, Sue’s focus on continual improvement and client satisfaction ensured that PSI’s approach was both innovative and client-centric. Their combined expertise laid a strong foundation for a company dedicated to excellence in custom software development and software consulting.
Over the years, PSI has remained steadfast in our mission, focusing on engineering and designing mission- and safety-critical software systems for highly regulated industries. Working closely with leaders in the medical, industrial, and military sectors, PSI has become a subject matter expert on FDA software requirements, SIL compliance, and MILTEC standards. Whether developing a new system from scratch or refactoring an existing code set, PSI’s time-tested software engineering principles always prioritize innovation, adaptability, and usability.
Today, under Sue’s leadership as CEO, PSI proudly stands as a woman-owned business. The company’s commitment to quality and client satisfaction remains at the forefront, guided by the same values that Walt and Sue instilled from the beginning. Walt also remains deeply engaged in PSI’s operations, keeping a pulse on projects, applying his decades of experience to guide the team, and providing strategic insight. Their legacy of treating client projects “as if they were our own” continues to drive PSI’s success and reputation as a trusted partner in creating breakthrough software solutions that exceed requirements and expectations. We lead with candor and openness—shaped by our family-business ethos and a mission to promote each client’s business strategy, competitiveness, and success.

Expert Engineers. Trusted Partners. Meet the PSI Team.
Our team of custom software developers, embedded systems engineers, and software consultants thrives on solving complex challenges for industries where precision and reliability are non-negotiable. Whether developing new systems, enhancing existing code, or even joining an in-progress project midstream to deliver consultative support, we bring deep expertise and a collaborative mindset to every effort we undertake.
More than just engineers, we are problem-solvers and trusted partners dedicated to delivering mission- and safety-critical software that exceeds expectations. Our 100% US-based team works closely with clients to ensure seamless integration, security, and long-term success.
Our Leadership
At PSI, experienced leadership drives project success. PSI’s leaders bring decades of expertise in custom software development, engineering for embedded and real-time systems, and software consulting, ensuring that every project balances the critical pillars of quality, cost, and schedule. Guided by a collaborative, client-focused approach, we lead with integrity, innovation, and a dedication to delivering breakthrough software solutions that can’t risk failure.






PSI is ready to help you meet industry-specific compliance requirements.
Meeting rigorous industry standards is a non-negotiable part of delivering mission-critical software. That’s why we adhere to several ISO standards and maintain compliance with recognized regulations in the medical, industrial, and government sectors. Our commitment to crucial requirements helps ensure your software aligns with the latest best practices.
Unmatched Expertise. Proven Results. Put Our Team's Experience to Work for Your Next Custom Project.
