https://alosha.dev/blog Notes on building privacy-first developer tools, from the Alosha studio. en Wed, 08 Jul 2026 00:00:00 GMT https://alosha.dev/blog/introducing-alosha-xlsx https://alosha.dev/blog/introducing-alosha-xlsx The npm spreadsheet shelf went stale. @alosha/xlsx is an ESM-first, dependency-light .xlsx reader and writer with an ExcelJS-compatible shim and a low-memory streaming writer. Eduardo Wed, 08 Jul 2026 00:00:00 GMT https://alosha.dev/blog/what-it-takes-to-parse-a-garmin-fit-file https://alosha.dev/blog/what-it-takes-to-parse-a-garmin-fit-file FIT is a binary protocol, not a text format. Semicircles, scaled fields, self-describing messages and half-counted cadence — here's what's actually inside a .fit, and what Stride absorbs so you don't have to. Eduardo Tue, 30 Jun 2026 00:00:00 GMT https://alosha.dev/blog/the-math-behind-offline-validation https://alosha.dev/blog/the-math-behind-offline-validation A regex checks the shape of an IBAN or a BSN. The check digit proves it could be real. Here's the arithmetic that makes offline validation possible — worked out by hand. Eduardo Mon, 29 Jun 2026 00:00:00 GMT https://alosha.dev/blog/website-monitoring-from-your-terminal https://alosha.dev/blog/website-monitoring-from-your-terminal Most uptime tools are dashboards you log into. Monitor is a config file and two commands — real-browser checks, alerts and reports, versioned with your code. Eduardo Wed, 17 Jun 2026 00:00:00 GMT https://alosha.dev/blog/why-we-built-stride https://alosha.dev/blog/why-we-built-stride Parsing a run sounds simple until you meet GPX, TCX and FIT in the wild. Stride turns any of them into clean metrics and charts with zero config. Eduardo Tue, 16 Jun 2026 00:00:00 GMT https://alosha.dev/blog/introducing-eu-validate https://alosha.dev/blog/introducing-eu-validate Checksum-accurate VAT, IBAN, BSN and KvK validation that runs entirely on your own machine — no network calls, no dependencies. Eduardo Mon, 15 Jun 2026 00:00:00 GMT https://alosha.dev/blog/why-we-retired-compressme https://alosha.dev/blog/why-we-retired-compressme How a single npm package, a docs site, and a commercial domain became three brands — and why we collapsed them into one. Eduardo Sat, 13 Jun 2026 00:00:00 GMT https://alosha.dev/blog/maintaining-open-source-with-ai https://alosha.dev/blog/maintaining-open-source-with-ai How a solo founder runs a portfolio of products by treating AI as the execution layer. Eduardo Fri, 12 Jun 2026 00:00:00 GMT