Senior Application Security Engineer

About FusionAuth

FusionAuth is a fast-growing startup and leading provider of customer identity and access management (CIAM) software headquartered in Denver, Colorado. Our mission is to make authentication and authorization simple and secure for every developer.  Our product helps businesses securely manage customer identities and access, ensuring a seamless and safe user experience for some of the largest brands in the world. We are committed to delivering exceptional value and satisfaction to our clients through top-notch service and support.  With a great team and strong investors, we are expanding our team to help accelerate our growth and take FusionAuth to the next level.

Job Summary

We are seeking a Senior Application Security Engineer to join our engineering team. In this role, you will be responsible for ensuring that our applications and infrastructure meet stringent security standards. Additionally, you will be instrumental in fostering a security-centric culture throughout the engineering teams. To excel in this position, you should possess a creative and quantitative mindset, along with a deep understanding of secure coding practices. A strong passion for authentication, authorization, and user management is essential. Prior experience in security-focused roles or practices, such as penetration testing (PEN testing), bug bounties, or similar endeavors, will be highly valued. This position is based in the Broomfield, CO area and requires part time attendance 1-2 days per week in the office.

Responsibilities

• Participate in threat modeling, code reviews, and security audits to strengthen our applications against vulnerabilities.
• Manage our bug bounty program by validating submissions and assessing awards.
• Research and integrate security tools into our development processes and pipelines.
• Design and implement new features with an emphasis on secure coding practices and risk mitigation.
• Write and maintain extensive, security-focused tests, including unit, integration, and vulnerability tests.
• Maintain our software with bug fixes, enhancements, and security patches.
• Produce clear, high-quality documentation for new features and security protocols.
• Contribute to platform roadmap planning and software architecture with an application security perspective, including prioritization of security-related bug fixes.
• Advocate for best practices in security within the Engineering organization, including developing training curricula on secure coding practices.

Qualifications Required

• 5+ years of professional software development experience with a significant focus on application security.
• Bachelor’s degree in Computer Science or equivalent practical experience with a strong understanding of secure software development principles.
• Expertise in Java web-application development and security.
• Proven experience in roles with security responsibilities, such as PEN testing, bug bounties, or similar security assessments.
• Highly proficient in object-oriented design and implementation with a secure development mindset.
• Strong understanding of the full web stack, including HTTP, TCP/IP, and REST, with an awareness of potential vulnerabilities in these areas.
• Experience building highly available, high-performance, scalable, and secure applications.
• Expertise in developing multi-threaded, API-first applications with secure data handling practices.
• In-depth knowledge of unit, integration, and vulnerability testing to ensure the robustness of our applications.
• Experience across the stack, from cloud infrastructure to front-end security practices.

All About You

We believe the following qualities will enhance your success in this role:

• You are analytical and data-driven, using metrics to understand and mitigate security risks.
• You have an interest in the authentication and authorization space, with a focus on security.
• You bring a strong yet flexible approach to security, ready to adapt as the landscape changes.
• You quickly learn new technologies and security practices.
• You’re excited about contributing to our open-source projects and building a secure ecosystem.
• You thrive in a startup environment and bring a proactive, security-focused mindset to your work.

Compensation

• $140 - 200k expected base salary range*

Onsite Perks & Campus Benefits

When you join FusionAuth’s Denver team, you’ll enjoy a modern campus experience designed for productivity, wellness, and community:

• Newly upgraded amenity spaces including a sleek tenant lounge and café with booth seating and collaborative workspaces.
• Access to a fitness studio, showers, lockers, and secure bike storage.
• Regularly stocked in-suite kitchen with a variety of snacks and beverages to keep you fueled throughout the day.
• Onsite café offering chef-driven menus with fresh, locally sourced, organic, and non-GMO options to suit diverse dietary needs. Easy ordering via app.
• 3-acres of green space, including communal parks and picnic areas, connected to miles of jogging, biking, and recreation trails.
• Yoga in the circle and wellness programs to enhance work-life balance.
• Dedicated outdoor workspaces and patio gathering areas.
• Ample on-site parking, easy freeway access, and high-speed fiber internet.
• Sustainability-minded campus and community initiatives, including support for regenerative agriculture programs.

Enjoy a high-tech business environment that inspires creativity and energizes your workday—all just minutes from the heart of Denver and Boulder.

*Pursuant to various state laws, we must display the pay range for this job. Since we are willing to hire within a broad spectrum of qualifications, this range is broad. The expected base salary may be adjusted based on individual qualifications, role, level and location.

Benefits

For full-time team members, we offer:

• Comprehensive health insurance including medical, dental, and vision coverage, with the company covering the majority of your medical premiums to keep your costs low
  • Fully employer-paid High Deductible Health Plan (HDHP) option paired with a Health Savings Account (HSA), including employer contributions
• Basic life insurance and short- and long-term disability coverage fully paid by the company for essential financial protection
• Voluntary life insurance options to provide additional financial protection for you and your loved ones
• Healthcare and Dependent Care Flexible Spending Accounts (FSAs) to save pre-tax dollars on eligible expenses
• 401(k) plan with company match to help you save for retirement
• Generous paid time off (PTO) plus paid company holidays to support work-life balance
• Employee Assistance Program (EAP) offering confidential counseling and support services
• Professional growth and development opportunities to boost your career journey
• Eligibility for performance-based bonuses or variable compensation tied to individual, team, or company results

Important Details

• Application Submission: We value authentic, thoughtful responses. Copy/pasted or AI-generated answers to application questions that don’t reflect your own experience may disqualify your application.
• Onsite Interview: As part of the FusionAuth hiring process, we typically invite finalists to visit our office for an onsite, in-person interview. This step gives both you and our team a chance to get to know each other better and make sure it feels like the right fit on both sides. We encourage candidates to plan accordingly, and FusionAuth will reimburse reasonable travel and lodging expenses related to the interview.
• Work Authorization: Applicants must be authorized to work for any employer in the U.S. We are unable to sponsor or assume sponsorship of an employment Visa at this time.

If you are passionate about technology that solves real-world customer problems, and want to join a company that is moving the industry forward, FusionAuth is a perfect fit for you!