Technical articles, practical notes, and lessons learned from mobile development, hybrid apps, testing, performance, debugging, and developer tooling.https://mikolajwilczek.dev/enhttps://mikolajwilczek.dev/blog/capacitor-chrome-preview/https://mikolajwilczek.dev/blog/capacitor-chrome-preview/Why I built a safe-area preview after hours, what I explored with CDP and Ink, and how it held up in use.Mon, 14 Sep 2026 00:00:00 GMTCapacitorChromeChrome DevTools ProtocolHybrid AppsDeveloper Toolinghttps://mikolajwilczek.dev/blog/android-emulator-capacitor-development-loop/https://mikolajwilczek.dev/blog/android-emulator-capacitor-development-loop/Use web previews, a scriptable Android Emulator, and physical phones as complementary feedback layers in a reliable Capacitor development loop.Mon, 24 Aug 2026 00:00:00 GMTAndroidAndroid EmulatorCapacitorDeveloper Toolinghttps://mikolajwilczek.dev/blog/boring-development-environments/https://mikolajwilczek.dev/blog/boring-development-environments/Manage Node, Ruby, Java, and project-specific CLIs with repository-owned versions, then decide when nvm, asdf, or mise fits.Thu, 13 Aug 2026 00:00:00 GMTDeveloper ToolingasdfmiseReproducibilityhttps://mikolajwilczek.dev/blog/openssl-s-server-https/https://mikolajwilczek.dev/blog/openssl-s-server-https/Use OpenSSL's built-in test server to run a temporary HTTPS endpoint while debugging TLS.Wed, 29 Jul 2026 00:00:00 GMTOpenSSLTLSDebuggingCommand Linehttps://mikolajwilczek.dev/blog/mobileconfig-profiles-ios-developers/https://mikolajwilczek.dev/blog/mobileconfig-profiles-ios-developers/A developer-focused look at iOS .mobileconfig profiles: what they configure, why a profile containing only a root CA added no value, and when to use one.Fri, 17 Jul 2026 00:00:00 GMTiOSCapacitorConfiguration ProfilesDeveloper Toolinghttps://mikolajwilczek.dev/blog/add-root-cert-ios-simulator/https://mikolajwilczek.dev/blog/add-root-cert-ios-simulator/Add a local root CA to iOS Simulator for HTTPS dev servers, Capacitor live reload, and proxy debugging.Mon, 06 Jul 2026 00:00:00 GMTiOSSimulatorCertificatesCapacitorIonicDebugginghttps://mikolajwilczek.dev/blog/appium-getting-started/https://mikolajwilczek.dev/blog/appium-getting-started/Learn why Appium is a powerful choice for mobile testing, how it differs from WebdriverIO, and how to get started with hybrid app testing.Tue, 30 Dec 2025 00:00:00 GMTMobileTestingAppiumWebdriverIOiOSAndroidAutomationhttps://mikolajwilczek.dev/blog/pruning-capacitor-storage/https://mikolajwilczek.dev/blog/pruning-capacitor-storage/Fix and prevent stuck secure storage data in Capacitor iOS apps. Learn why iOS Keychain persists after app deletion and how to handle it.Thu, 28 Aug 2025 00:00:00 GMTiOSCapacitorSecurityMobileKeychainhttps://mikolajwilczek.dev/blog/js-functions-leak/https://mikolajwilczek.dev/blog/js-functions-leak/Understanding and preventing memory leaks in React caused by closures and nested functions. Practical approaches with WeakMap, WeakRef, and manual cleanup.Thu, 15 Aug 2024 00:00:00 GMTJavaScriptReactPerformanceMemory Managementhttps://mikolajwilczek.dev/blog/expo-ios-tests/https://mikolajwilczek.dev/blog/expo-ios-tests/Learn how to test native code in React Native apps using Expo modules with native iOS testing frameworks.Tue, 09 Jan 2024 00:00:00 GMTiOSReact NativeExpoTestingSwiftObjective-Chttps://mikolajwilczek.dev/blog/lsof/https://mikolajwilczek.dev/blog/lsof/Quick solution to kill processes using specific ports on macOS and Linux without restarting your computer.Sat, 20 May 2023 00:00:00 GMTmacOSLinuxDevOpsCommand Line