Portfolio

Projects & domain portfolio.

Open-source apps and domains — some for sale, some already in use.

Projects

Two sites I maintain as free, open tools.

skanfirmy.pl

Free tools to check Polish companies by NIP or KRS number: VAT White List, KRS data, bank account verification, micro-account generator, PKD codes, late-payment interest, VIES. Data straight from official government registries (MF, MS, GUS). Also available as an MCP server for AI agents.

Open skanfirmy.pl →

otwarteAPI.pl

API catalog · PL / EU

otwarteAPI.pl

A catalog of public Polish and EU APIs (VAT White List, KRS, NBP, GUS BDL, ECB, Eurostat, and more). 21 entries, for humans and AI agents alike. Machine manifest in the ARD standard (ai-catalog.json). Listed on llms-txt-hub.

Open otwarteAPI.pl →

Domains for sale

Available, ready to transfer. Price negotiable — reach out via LinkedIn.

cyberwarsaw.com Ask for a quote → cyberwarsaw.eu Ask for a quote → cyberwarsaw.online Ask for a quote → cyfrowawarszawa.com Ask for a quote → cyfrowyolsztyn.eu Ask for a quote → cyfrowyolsztyn.online Ask for a quote → cyfrowyolsztyn.pl Ask for a quote →

Domains in use

Redirect to skanfirmy.pl — extra shortcuts to the same tool.

firmacheck.pl → skanfirmy.pl firmcheck.pl → skanfirmy.pl danekontrahent.pl → skanfirmy.pl danekontrahenta.pl → skanfirmy.pl fakturacheck.pl → skanfirmy.pl krscheck.pl → skanfirmy.pl

Contact

Reach out via LinkedIn — the fastest way.

Message on LinkedIn