Fastly helps people stay better connected with the things they love. Fastly’s edge cloud platform enables customers to create great digital experiences quickly, securely, and reliably by processing, serving, and securing our customers’ applications as close to their end-users as possible — at the edge of the Internet. The platform is designed to take advantage of the modern internet, to be programmable, and to support agile software development. Fastly’s customers include many of the world’s most prominent companies, including Vimeo, Pinterest, The New York Times, and GitHub.
We're building a more trustworthy Internet. Come join us.
Posting Open Date: Oct 20, 2025
Anticipated Posting Close Date*: Nov 21, 2025
*Job posting may close early due to the volume of applicants.
Senior Application Security Engineer
We are looking for a Senior Application Security Engineer to join a small team that has a big impact protecting a critical piece of the Internet's infrastructure. We believe in a sensible, risk-based approach to vulnerability management, making sure we balance what's best for the business with what works for our developers. You’ll be responsible for analyzing vulnerability findings and actively working with engineering teams and security tools to mitigate risk across Fastly. The team believes in the importance of the larger security community. We encourage continuous learning, speaking at conferences, and contributing to open-source projects. We are a fully distributed security team with the commitment and tools in place to make it work.
What You'll Do:
- Perform risk-based vulnerability assessments to prioritize critical issues
- Collaborate with engineering teams to coordinate vulnerability remediation
- Automate security workflows by developing custom internal tooling and scripts
- Manage vulnerability-related security incidents
- Build security guardrails directly into our CI/CD pipelines to proactively prevent vulnerabilities
- Drive security initiatives that shape our application security program
What We're Looking For (Required):
- 5+ years hands-on experience implementing and running SAST, DAST, and SCA tools
- Ability to implement security policies without compromising developer experience
- Experience communicating complex security changes and requirements to engineering teams
- Proficiency in one or more general-purpose programming languages (Rust, Ruby, Go, or Python)
- Familiarity with security testing tools, such as Burp Suite and nmap
- Strong networking fundamentals and knowledge of cloud-native environments and Kubernetes.
We’ll be super impressed if you have experience in any of these:
- In-depth knowledge of Linux/Kernel internals, including analyzing AMD and Intel vulnerabilities
- Proficiency in Rust and Terraform
- Experience with offensive security, including penetration testing or red teaming
Work Hours:
- This is a full-time position that requires availability during core business hours. You'll also participate in an on-call rotation to advise on security incidents outside of business hours (approximately one week per quarter).
Work Location(s) & Travel Requirements:
This position is open to the following preferred office locations:
- New York, NY
- San Francisco, CA
- Denver, CO
Fastly currently embraces a largely hybrid model for most roles which allows employees flexibility to split their time between the office and home.
This position may require travel as required by your role or requested by your manager.
SF / LA Fair Chance Ordinance Statement
Pursuant to the San Francisco Fair Chance Ordinance and the Los Angeles Fair Chance Initiative for Hiring Ordinance, we will consider for employment qualified applicants with arrest and conviction records.
Salary:
The estimated salary range for this position is $181,220 to $217,464.
Starting salary may vary based on permissible, non-discriminatory factors such as experience, skills, qualifications, and location.
This role may be eligible to participate in Fastly’s equity and discretionary bonus programs.
Benefits:
We care about you. Fastly works hard to create a positive environment for our employees, and we think your life outside of work is important too. We support our teams with great benefits that start on the first day of your employment with Fastly. Curious about our offerings?
We offer a comprehensive benefits package including medical, dental, and vision insurance. Family planning, mental health support along with Employee Assistance Program, Insurance (Life, Disability, and Accident), a Flexible Vacation policy and up to 18 days of accrued paid sick leave are there to help support our employees. We also offer 401(k) (including company match) and an Employee Stock Purchase Program. For 2025, we offer 11 paid local holidays, 11 paid company wellness days.
Why Fastly?
We have a huge impact. Fastly is a small company with a big reach. Not only do our customers have a tremendous user base, but we also support a growing number of open source projects and initiatives. Outside of code, employees are encouraged to share causes close to their heart with others so we can help lend a supportive hand.
We love distributed teams. Fastly’s home-base is in San Francisco, but we have multiple offices and employees sprinkled around the globe. As a new hire, you will be able to attend our IN-PERSON new hire orientation in our San Francisco office! It is an exciting week-long experience that we offer to new employees to build connections with colleagues across Fastly, participate in hands-on learning opportunities, and immerse yourself in our culture firsthand.
We value diversity. Growing and maintaining our inclusive and diverse team matters to us. We are committed to being a company where our employees feel comfortable bringing their authentic selves to work and have the ability to be successful -- every day.
We are passionate. Fastly is chock full of passionate people and we’re not ‘one size fits all’. Fastly employs authors, pilots, skiers, parents (of humans and animals), makeup geeks, coffee connoisseurs, and more. We love employees for who they are and what they are passionate about.
We’re always looking for humble, sharp, and creative folks to join the Fastly team. If you think you might be a fit please apply! A fully completed application and resume or CV are required when applying.
All job applications must be submitted through our official careers site at www.fastly.com/about/careers. We will never request sensitive information, such as your Social Security number, bank account or credit card information during the application process.
Fastly is committed to ensuring equal employment opportunity and to providing employees with a safe and welcoming work environment free of discrimination and harassment. Our employment decisions are based on business needs, job requirements and individual qualifications. All qualified applicants will receive consideration for employment without regard to age, ancestry, color, family or medical care leave, gender identity or expression, genetic information, marital status, medical condition, national origin, family or parental status, physical or mental disability, political affiliation, protected veteran status, race, religion, sex (including pregnancy), sexual orientation, or any other characteristic protected by applicable laws, regulations and ordinances.
Consistent with the Americans with Disabilities Act (ADA) and federal or state disability laws, Fastly will provide reasonable accommodations for applicants and employees with disabilities. If reasonable accommodation is needed to participate in the job application or interview process, to perform essential job functions, and/or to receive other benefits and privileges of employment, please contact your Recruiter, or the Fastly Employee Relations team at [email protected] or 501-287-4901.
Fastly collects and processes personal data submitted by job applicants in accordance with our Privacy Policy. Please see our privacy notice for job applicants.
Top Skills
Fastly Denver, Colorado, USA Office
Denver, CO, United States
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