About
I am Ratomir Jovanovic. I have spent 18 years building products across SaaS, fintech and payments, much of it in regulated, audited and security-sensitive environments.
What I work on now
I build payment infrastructure and security governance tools. On GitHub I maintain PandaPayLens, an open-source, local-first toolkit for debugging payment integrations, and I review payment and webhook code in other projects. The open-source page lists the public repositories and contributions that F4 can verify from GitHub.
My current ventures, as listed on my GitHub profile, are Payshen (payment orchestration, where I am founder and managing director), afend (ISO/IEC 27001:2022 readiness), Nanotesting (automated security assessment) and SodaSoft (a venture studio). Payshen's client libraries for PHP, Python and WooCommerce are public under the meetsodasoft organization.
Background
Before this I was Head of Product at Webio (2023 to 2025), working on product and QA governance for a platform serving enterprise clients in regulated collections and payments, inside an ISO/IEC 27001-certified environment. Earlier roles were UX Enterprise Architect at Japan Tobacco International, Chief User Experience Architect at Crossover for Work, and Chief Product Officer at Skout Deals. I am an ISO/IEC 27001:2022 Lead Auditor (CQI/IRCA).
Why F4 exists
Most of what makes engineering work good or bad is invisible in a finished product: the constraint that ruled out the obvious design, the bug that only appeared on a CI runner, the test that proved a fix. F4 keeps that record. Every project page and problem record links to the commits, issues and pull requests behind it, and anything without evidence is left out.
Elsewhere
GitHub is the primary record of my work: github.com/ratomirjovanovic. My personal site with essays on GRC, security, product and payments is ratomir.com.