Nebula

Screen recordings that edit themselves. Native macOS, written in Swift, scriptable from Claude.

What it does

• Records a display, a window or an area at native Retina resolution and 60 fps (HEVC), with microphone and system audio. Pause, restart or discard from a floating control. The cursor, clicks and shortcuts are recorded separately so they can be redrawn smoothly.
• Polish in one click:
  • zooms on clicks and typing, panning between nearby targets instead of zooming out and back in
  • cuts dead air and speeds up long typing
  • smooths the cursor and adds click effects
• Looks right by default. A window recording keeps its real on-screen size over the wallpaper that was behind it, on a frame shaped like your screen. Full-screen recordings fill the frame.
• Edits on a timeline: cuts, speed, zooms, blur/pixelate/spotlight masks, text and arrows, per-section volume, music that ducks under your voice, noise reduction, and on-device captions (WhisperKit).
• Exports MP4 (H.264 or HEVC, up to 4K60) or GIF. You can also copy the video or a single frame to the clipboard.
• ⌘K opens every command, style presets save a look, and .openscreen projects can be imported.
• MCP server built in: Claude can read the timeline, run Polish, add zooms and cuts, change the look, record and export. Each edit appears live in the editor and can be undone with ⌘Z.

Install

Download the DMG from Releases, open it and drag Nebula to Applications. On first launch, macOS asks for Screen Recording permission. Microphone and Accessibility permissions are optional: Accessibility lets Polish see clicks and text fields.

Connect Claude

Nebula's MCP server listens on 127.0.0.1:39351. To add it to Claude Code:

claude mcp add --transport http --scope user nebula http://127.0.0.1:39351/mcp

Then ask, for example: "Polish my latest recording, blur the email field around 0:12 and export a 1080p MP4."

Build from source

You need Xcode 26 and XcodeGen.

xcodegen generate

open Nebula.xcodeproj

The app target is a thin shell. Everything else lives in the Packages/NebulaKit Swift package, whose tests run with:

swift test --package-path Packages/NebulaKit

See docs/ARCHITECTURE.md for how the modules fit together and docs/SPEC.md for the product spec.

Maintainer

Nebula is made by Rune and maintained by Soham Samal (@sazuyakun). Open an issue for bugs and ideas; pull requests are reviewed by the maintainer.

License

MIT © Rune. The Manrope typeface is bundled under the SIL Open Font License.