I built Skim: a free open-source Email client for Windows with BYOK AI (MIT)

I built Skim because I tried to find a Windows email client that doesn't suck that hard and couldn't really find one. It's not rocket science to vibecode one, right? Why has nobody done it before? Or is everyone just okay with bloated Outlook or archaic Thunderbird? Skim - free, open-source, MIT-licensed minimalistic offline-first email client with BYOK AI. Quick feature list: Installer under 5 MB Bring Your Own Key to enable AI features: Anthropic/OpenRouter, or any OpenAI-compatible server (including a local one) No menu. Minimalistic and contextual interface - buttons are shown only when you need them Keyboard-first controls: shortcuts for everything, no mouse needed Sweet warm zine design Super modest resource consumption AI features are pretty basic: Cowriter that can scan your recently sent emails, adopt your style, and then write emails and replies that sound like you "Ask this email" - chat with a particular email; it can read attachments and follow links inside it Agentic search across all connected inboxes; the "Ask your inbox" feature can scan your whole inbox One-click summarization and translation A few things I'm actually proud of under the hood The UI part is easy to vibecode. These bits were not. Getting the installer under 5 MB took real work. panic = "abort" alone dropped about 6 MB of unwind tables from the binary, that's 23% off the NSIS installer. I ship a single crypto backend (ring, with aws-lc-rs switched off) so I'm not compiling a second, unused crypto library into the thing. I even wrote a tiny Vite plugin that deletes legacy .woff fonts, since WebView2 always uses woff2 anyway. Pretty much every dependency in Cargo.toml carries a comment justifying its feature flags in kilobytes saved: rustls = { version = "0.23" , default-features = false , features = [ "ring" ] } # aws-lc-rs would compile a second, unused crypto library. ~2 MB of dead weight. No Electron, no bundled Chromium. Tauri 2 uses the system WebView2, so it installs per-user wit