Hey DEV! I'm Stefan — TYPO3 dev, and I just launched a page of free browser tools

Hey, I'm Stefan

I'm a freelance web designer & developer based in Klagenfurt, Austria — though these days most of my work happens for clients well beyond Austria's borders. My focus is TYPO3: building and maintaining sites end-to-end, from branding and visual identity through to a finished, working website. Alongside that I do graphic design and video editing, so a project usually has me moving between code, layout, and media in the same afternoon.

I'm mostly self-taught on the dev side, which means I've spent a lot of time in the last few years pulling apart how things work under the hood — TypoScript, page performance, and lately the more technical end of SEO (security headers, structured data, Core Web Vitals). This post is partly an excuse to talk about the result of that: a small toolset I just shipped on my site.

What I built

I wanted a set of quick, no-nonsense tools I could point clients (and myself) to instead of juggling five different sketchy websites full of ads. So I built my own, all living at stefan-andres.at/tools:

• Palette & Contrast Checker — pick colors and instantly check contrast ratios for accessibility.
• Icon & Favicon Generator — drop in a logo (PNG, SVG, even AI/PDF/EPS) and get every icon size you need, ready to download.
• Web Image Optimizer — compress images for the web without leaving your browser.
• CSS Minifier and JS Minifier — paste your code, get a minified version back.
• SEO & Performance Check — enter a URL and get an on-page SEO report plus real Google PageSpeed metrics (LCP, FCP, CLS) with plain-language suggestions.

Most of these run entirely client-side — nothing you upload leaves your browser. Under the hood I'm using libraries like Terser and csso for minification and pdf-lib / pdf.js to handle vector file rendering for the icon generator. The SEO checker is the one exception — it calls a small PHP backend on my own server, which in turn talks to the Google PageSpeed Insights API.

What I learned building it

A few things stuck with me:

• Bilingual UX is more work than it looks. The whole tools page runs in English and German, including the dynamically generated SEO report text — which meant threading a lang parameter all the way from the front-end fetch call through to the PHP backend's string tables.
• Client-side file processing has come a long way. Being able to minify JS/CSS or rasterize a vector PDF entirely in the browser, with no server round-trip, still feels a little magical.
• Security headers and structured data are underrated. Once I started running my own SEO tool against my own site, I found (and fixed) my own gaps — missing CSP, missing JSON-LD, missing an apple-touch-icon. Nothing dramatic, just easy wins that add up.

Say hi

I'm always happy to talk TYPO3, front-end tooling, or technical SEO — and I'm open to freelance work and collaborations, wherever you're based. Feel free to check out the tools, break them, and tell me what's missing. 🙂

Cheers,
Stefan