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Application Security Engineer

You stop vulnerabilities from being written, rather than finding them after they ship.

No degree needed Hard. It is two disciplines, and you cannot fake either.


Read this first

Test only systems you own or have written permission to test, and follow a project's published disclosure policy. Unauthorised access is a criminal offence in most countries even when your intent is to help.

Can I actually do this?

Open without a degree, and one of the better-paid places a self-taught developer can end up. It is not an entry-level role: you need to read and write code well before the security layer means anything. The most common route is a few years of development followed by a deliberate turn toward security. Everything below is free.

Who it suits. People who like reading other people's code and asking what happens if this input is hostile.

Runway. Years, and you need to be able to read code fluently first.

Coming from another job?

Coming from development? That is the strongest starting point, and it is what most job ads are quietly asking for. Backend Developer Penetration Tester Security Analyst

Also advertised as

  • AppSec Engineer
  • Product Security Engineer
  • Software Security Engineer
  • Secure Code Reviewer

The route

Four stations, in order. Each one is a thing you finish before the next matters.

  1. Station one

    Learn it free

    Only the best few, deliberately. Every one of these is free to use — the pill on each card says exactly what is and isn't free.

    OWASP Top 10 Proactive Controls

    Free to learn · no certificate

    The defensive counterpart to the famous Top 10 — what to build rather than what to fear. Free and open. This is the more useful of the two for this role.

    OWASP Cheat Sheet Series

    Free to learn · no certificate

    Concrete, per-topic guidance you will actually cite in code review. Free.

    PortSwigger Web Security Academy

    Free to learn · no certificate

    You cannot defend against what you have never exploited. Free labs, no certificate.

    See the full catalog in the explorer →

  2. Station two

    Attest strategically

    Nothing named. Certifications exist in this space and some carry weight, but appsec hiring runs on whether you can find a real flaw in real code and explain the fix to the person who wrote it. A public code review or a responsibly-disclosed finding does more than any certificate, and costs nothing.

    Nothing here is worth paying for

    No credential needed

    Nothing named. Certifications exist in this space and some carry weight, but appsec hiring runs on whether you can find a real flaw in real code and explain the fix to the person who wrote it. A public code review or a responsibly-disclosed finding does more than any certificate, and costs nothing.

  3. Station three

    Prove it

    A certificate says you passed a test. These say you can do the job.

    A security fix merged into real code

    Find a flaw in an open-source project, disclose it responsibly, and submit the patch. Public, dated, and attributable.

    A threat model for something you built

    What an attacker wants, how they would get it, what you did about it. One page.

    A review comment that changed a design

    Show yourself persuading an engineer, not overruling them. Appsec fails when it is a gate rather than a colleague.

  4. Station four

    Get hired

    Search these exact titles

    • application security engineer
    • appsec engineer
    • product security engineer
    • security engineer

    Who hires for this. Software companies with something worth stealing, fintech, health tech, and consultancies doing secure code review.

    A responsibly-disclosed finding with a merged patch is public and checkable, which is rare evidence in security work. That is our reasoning about what is inspectable, not a hiring statistic we have verified.

    On salary

    We don't publish salary estimates. Numbers copied between blogs drift from reality, and a wrong number costs you real negotiating power. When we have a verified public source, it goes here with its date.


Where this route continues

· How we verify