In-depth guides on personal finance, taxes, and developer tooling from FlexUtil, authored by Sergei Selivanov.https://flexutil.com/enhttps://flexutil.com/guides/mortgage-planning/https://flexutil.com/guides/mortgage-planning/A practical guide to planning a mortgage in Europe. Covers rate shopping, loan term tradeoffs, amortization, early-payoff strategies, and the invest-vs-paydown decision.Tue, 21 Apr 2026 00:00:00 GMTSergei Selivanovhttps://flexutil.com/guides/estonian-employment/https://flexutil.com/guides/estonian-employment/How employment taxes, VAT, and the new vehicle tax work in Estonia. Covers gross vs net, the II pillar, reverse charge, and the 2025 registration fee changes.Tue, 21 Apr 2026 00:00:00 GMTSergei Selivanovhttps://flexutil.com/guides/developer-data-formats/https://flexutil.com/guides/developer-data-formats/Practical rules for JSON, Base64, UUIDs, and passwords — how they work, when to pick which, and the subtle mistakes that break things in production.Tue, 21 Apr 2026 00:00:00 GMTSergei Selivanov