Maksim ShcherboI build infrastructure that must not fail — and stop outages before they happen.https://happygopher.nl/en-usThu, 16 Jul 2026 00:00:00 GMTMaking Operational Decisions Explainablehttps://happygopher.nl/writing/making-operational-decisions-explainable/https://happygopher.nl/writing/making-operational-decisions-explainable/Operational software should log decisions, not just actions. How I structured a Kubernetes controller so its policy stayed explicit, reviewable, and observable.Thu, 16 Jul 2026 00:00:00 GMTarchitecturedistributed-systemsgoreliabilityDesigning Hot-Reloadable Per-Tenant Routinghttps://happygopher.nl/writing/mev-boost-hot-reloadable-relay-config/https://happygopher.nl/writing/mev-boost-hot-reloadable-relay-config/Designing per-tenant relay routing for MEV-Boost: from acceptance criteria to a lock-free, zero-downtime config reload in Go, and what the benchmarks showed.Tue, 14 Jul 2026 00:00:00 GMTdistributed-systemsarchitectureperformancegoA Password Hash on Every API Call: The Bug That Restarted Our Validators Every Two Hourshttps://happygopher.nl/writing/lighthouse-web3signer-scrypt/https://happygopher.nl/writing/lighthouse-web3signer-scrypt/Updating validators via Lighthouse restarted our pods every two hours. The cause: scrypt hashing on every update. A 20-line guard, merged upstream in v4.1.0.Mon, 06 Jul 2026 00:00:00 GMTdebuggingperformanceethereumrustWhat Actually Moved the Score: A Rust Auth Server on highload.funhttps://happygopher.nl/writing/highload-fun-auth-server/https://happygopher.nl/writing/highload-fun-auth-server/A Rust auth server on highload.fun, from 9.198s to a 5.416s record. The wins looked like I/O — but the real lever turned out to be CPU cache locality.Sun, 05 Jul 2026 00:00:00 GMTperformancerustTCP_NODELAY: One Line, 135x Faster in KurrentDB's Rust Clienthttps://happygopher.nl/writing/kurrentdb-rust-nagle/https://happygopher.nl/writing/kurrentdb-rust-nagle/A read from a local KurrentDB took 40ms while the database answered in ~1ms. The fix was one socket option: TCP_NODELAY made the client 135x faster.Wed, 24 Jun 2026 00:00:00 GMTperformancedebuggingrustWhy VS Code can't install extensions to a remote when your local ones are read-onlyhttps://happygopher.nl/writing/vscode-remote-readonly-extensions/https://happygopher.nl/writing/vscode-remote-readonly-extensions/A read-only (Nix-managed) local extensions directory makes VS Code Remote installs fail with EntryWriteLocked. Why it happens, and how to work around it.Tue, 23 Jun 2026 00:00:00 GMTtoolingBuilding Financial Infrastructure That Must Not Failhttps://happygopher.nl/writing/building-financial-infrastructure-that-must-not-fail/https://happygopher.nl/writing/building-financial-infrastructure-that-must-not-fail/Senior engineer sharing lessons from building Ethereum staking infrastructure that must not fail — reliability, testing, and quality at scale.Tue, 21 Oct 2025 00:00:00 GMTreliabilityarchitecturedistributed-systems