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Hey HN. I'm Teo, I've spent 10+ years doing application security assessments and training dev teams. The same vulnerabilities kept coming back, so I built something to fix that.

AppSec.fi is an interactive platform where developers learn application security hands-on, matched to their actual stack (languages, cloud provider, CI/CD). Exercises include real attacks, real defense, AI-evaluated code reviews, and simulated environments. Everything runs in the browser.

We're launching a 2-week free trial starting tomorrow (April 1st). Today is the last day to sign up as an early adopter, which gets you 50% off permanently if you continue.

https://appsec.fi/en/

Happy to answer any questions about the platform or AppSec training in general.

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