Fyne
Cross-platform GUI toolkit for Go — the most popular native Go GUI library. Fyne uses OpenGL for rendering (not WebView like Wails/Electron), enabling truly native-looking widgets on Windows, macOS, Linux, iOS, Android, and Raspberry Pi from a single Go codebase. Provides Material Design-inspired widgets, layouts, canvas drawing API, custom themes, data binding, file dialogs, and notifications. Unlike Wails (web UI), Fyne apps have no HTML/CSS — all UI is pure Go. Fyne Develop tool for app distribution and packaging.
Score Breakdown
⚙ Agent Friendliness
🔒 Security
Native app security — OS sandbox on mobile platforms. No web rendering attack surface. CGo dependency requires C library hygiene. App signing required for macOS/iOS distribution. No network exposure in UI layer.
⚡ Reliability
Best When
You're writing a pure Go desktop (or mobile) app and want a single codebase UI toolkit without web technologies — Fyne gives you cross-platform native GUI entirely in Go.
Avoid When
You need web-technology UI (use Wails), exact platform-native widget appearance, or browser deployment. Fyne's custom rendering means consistent cross-platform look but not OS-native widgets.
Use Cases
- • Build cross-platform desktop agent GUIs in pure Go without web technologies — native widget toolkit for Go agent management tools that run on Windows, macOS, and Linux
- • Create mobile iOS/Android agent companion apps using Fyne's mobile support — same Go codebase compiles to both desktop and mobile with platform-appropriate UI adaptations
- • Build data visualization dashboards for agent monitoring using Fyne's canvas API — custom drawing primitives for graphs, timelines, and real-time agent metric displays
- • Package agent CLI tools with optional GUI mode using Fyne — add a settings window or status dialog to existing Go CLI agents without a separate frontend language
- • Develop Raspberry Pi agent interfaces using Fyne's ARM/Linux support — touch-friendly UI for embedded agent devices with OpenGL rendering
Not For
- • Teams wanting web-based UI in desktop apps — use Wails or Electron for web technology UI; Fyne is pure Go with OpenGL rendering, no HTML/CSS/JS
- • Apps requiring platform-native widget exact appearance — Fyne has its own widget style (Material Design-inspired); it won't match native macOS aqua or Windows Fluent exactly
- • Web browser targets — Fyne doesn't compile to WebAssembly for browser use; use GopherJS or Go+WASM for browser-based Go UIs
Interface
Authentication
GUI toolkit — no auth concepts. Auth for external services handled in Go application logic behind the UI.
Pricing
Fyne is BSD 3-Clause licensed, maintained by Fyne Labs. Free for all use including commercial applications.
Agent Metadata
Known Gotchas
- ⚠ UI updates must happen on main thread — all Fyne widget updates must occur on the GUI goroutine; use fyne.CurrentApp().Driver().RunOnMain() for goroutine-to-UI updates; direct widget mutation from background goroutine causes race conditions
- ⚠ OpenGL requires C dependencies — Fyne uses CGo with OpenGL/GLFW; CGo must be enabled and platform GL libraries installed; `CGO_ENABLED=0` builds don't work; Docker cross-compilation requires OpenGL libraries
- ⚠ Mobile builds require platform SDKs — iOS requires Xcode on macOS; Android requires Android NDK; `fyne package -os android` fails without proper NDK configuration
- ⚠ Custom widget layout requires understanding Fyne's layout contract — implementing fyne.Widget requires Layout(), MinSize(), and Refresh() methods; incorrect MinSize causes layout clipping or infinite layout loops
- ⚠ Data binding is one-way by default — fyne.NewStringBinding creates observable bindings but two-way binding requires Bind() on widget and explicit Set() calls; forgetting Refresh() after external data changes doesn't update UI
- ⚠ App packaging differences by platform — macOS requires code signing for distribution; Windows requires icon embedding via fyne package; Linux FlatPak/AppImage bundles are separate tools; distribution is not automatic
Alternatives
Full Evaluation Report
Detailed scoring breakdown, competitive positioning, security analysis, and improvement recommendations for Fyne.
Scores are editorial opinions as of 2026-03-06.