Senior Application Security Engineer

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