Senior Full Stack Software Engineer Jobs in Longmont, CO

As the leading provider of Cybersecurity-as-a-Service (CSaaS), RADICL is revolutionizing advanced cyberthreat protection for small and medium-sized businesses (SMBs) in the U.S. Defense Industrial Base (DIB) and other regulated industries. No longer should SMBs be satisfied with lack luster solutions delivering lack luster protection. RADICL is ushering in a new era of turn‑key and affordable cyberthreat protection via its AI‑powered virtual SOC platform that allows human and digital agents to quickly and seamlessly become SMBs’ day‑to‑day compliance and security operations team.

RADICL’s turn‑key CSaaS offering uniquely combines compliance management with AI and expert‑driven 24/7 security operations. We guide customers to regulatory and best practice adherence with standards like CMMC and NIST CSF while also delivering 24/7 threat monitoring, deep‑spectrum™ threat hunting, incident response, vulnerability management, and security awareness training.

With RADICL, customers can stay mission focused, confident their front, rear, and flank are protected, affordably and without compromise.

If you’re excited about working with industry experts to help SMBs focus on growing their businesses without the constant worry of security and compliance risks, we invite you to join us in our mission to protect American businesses and drive innovation in cybersecurity.

• Lead the design and delivery of scalable, secure, cloud‑native systems powering RADICL’s cybersecurity platform. This role owns features end‑to‑end—from architecture and backend services to frontend user experience—while helping shape engineering standards, system direction, and technical strategy.
• Operate as a senior technical contributor responsible for building resilient distributed systems, maintaining the highest‑quality engineering standards, and driving execution across the full application stack.

• Build and evolve modern frontend applications using TypeScript, React and NodeJS.
• Architect, design, and implement scalable backend services using Golang.
• Own features end‑to‑end across API, service, infrastructure, and UI layers.
• Lead technical design discussions and influence system architecture decisions.
• Improve platform scalability, observability, reliability, and security posture.
• Collaborate cross‑functionally with product, security, and operations teams.
• Opportunity to mentor engineers and provide technical leadership across the team.
• Contribute to incident response, performance tuning, and production troubleshooting.
• Maintain architectural documentation and technical decision records.

• 7+ years of professional software engineering experience.
• Strong full‑stack development experience using React, API (NodeJS), and a relational database.
• Expert proficiency in TypeScript, Golang, or comparable modern languages.
• Production experience with cloud platforms (AWS, GCP, or Azure).
• Deep understanding of API design, system scalability, and performance optimization.
• Experience with containerization and orchestration (Docker, Kubernetes).
• Strong experience with Git workflows and modern SDLC practices, excellent written communication skills.

• Experience building security, compliance, or mission‑critical platforms.
• Familiarity with PostgreSQL, Kafka, Elasticsearch, or large‑scale data systems.
• Experience with GitHub Actions or modern CI/CD tooling.
• Infrastructure‑as‑Code experience (Terraform, Ansible).
• Experience operating high‑availability SaaS platforms.
• Background in cybersecurity, defense, or regulated environments; startup or high‑growth company experience.

If the above excites you, RADICL Defense is seeking high performing, motivated individuals to join our mission. As an early member, you will work closely alongside an experienced founding team and realize the life‑changing experience of building a company. You will work with the latest technologies in software, cybersecurity, and cloud and will have a significant impact on the formation of our platform and offering.

You enjoy fast‑paced environments, bring a positive attitude, and excel at getting things done. You enjoy being part of a high‑performing team and are also able to self‑direct and self‑start. You consider yourself to be top tier talent and are eager to help others raise their game. You enjoy working with customers, are an excellent communicator, and able to engage and interact with people of various backgrounds and skill levels. You want your work to have meaning, to be important. You want to be part of creating something great.

At RADICL, we prioritize our culture and believe the strongest teams are built through daily, side‑by‑side collaboration and experiential sharing. We also value individual freedom and flexibility. For this reason, we have a hybrid work model. As a team, we are in office M/W/Th with work‑from‑home on Tuesdays and Fridays. For remote positions, periodic travel to Boulder will be expected to participate in company events and meaningful side‑by‑side collaboration opportunities.

RADICL offices are in downtown Boulder, Colorado with easy‑to‑access employee parking provided by the company. We offer comprehensive, competitive benefits including health, dental, and vision as well as 401K and a responsible PTO plan.

We encourage motivated, talented, mission‑oriented, and fun people to apply. Let’s do this!

The pay range for this role is: 150,000 - 200,000 USD per year (Walnut St.)