ObviousSaveMD

ObviousSaveMD is a small native macOS Markdown and text editor built with SwiftUI and AppKit. It keeps Markdown as plain text in an NSTextView; there is no HTML preview, web view, script execution, or remote media loading path.

30-second proof

• Problem: many Markdown editors turn simple text editing into a preview/rendering surface with extra file and web risk.
• System: native macOS editor shell using SwiftUI and AppKit, with plain-text Markdown editing in NSTextView.
• Safety boundary: opens are limited to Markdown/text document types and validated after selection; hostile file intake rejects symlinks, non-regular files, named pipes, oversized files, NUL bytes, and invalid UTF-8.
• Correctness: stale async open results are ignored when the current document changed or a newer open request happened.
• Stack: Swift 6.3, SwiftUI, AppKit, Swift Testing, GitHub Actions, native app bundle script.

Recruiter signal: this is a native desktop app proof artifact focused on local-first UX, file-safety boundaries, and tested AppKit edge cases rather than a web wrapper.

Features

• Open and edit Markdown or plain-text files.
• Save existing files or save untitled drafts with Save As.
• Show the current file name, path, save state, and macOS document-edited indicator.
• Wrap long lines with a vertical scrollbar.
• Preserve UTF-8 text, including non-ASCII Markdown.

File Safety

Opening a file is intentionally conservative:

• The open dialog is limited to Markdown and plain-text document types, with file-content validation after selection.
• Reads happen off the main actor so slow file I/O does not block the UI thread.
• The file reader rejects symlinks, non-regular files, named pipes, oversized files, NUL-containing data, and invalid UTF-8 before loading content into the editor.
• The default read limit is 20 MiB.
• If an open operation finishes after the current document changed or after a newer open request, the stale result is ignored.

Saving rejects symlink and non-regular existing destinations before writing. The current app bundle is not sandboxed, does not use security-scoped bookmarks, and relies on normal macOS file permissions and user-selected paths.

Use

Build the app bundle, then open the printed .app path in Finder. Use Open, Save, and Save As from the toolbar or the standard keyboard shortcuts:

• Open: Command-O
• Save: Command-S
• Save As: Shift-Command-S

The editor prompts before replacing or closing a document with unsaved changes.

Requirements

• macOS 14 or newer
• Xcode or Swift toolchain compatible with Swift 6.3

Build

Run the test suite:

swift test

Build a Finder-launchable app bundle:

Scripts/build-app.sh

The script prints the generated absolute app path. The exact path varies by checkout and configuration, for example:

/path/to/ObviousSaveMD/.build/<triple>/debug/ObviousSaveMD.app

To build a release bundle:

CONFIGURATION=release Scripts/build-app.sh

GitHub Actions runs swift test on push and pull request events via .github/workflows/ci.yml.

Project Layout

• Sources/ObviousSaveMD: SwiftUI/AppKit app shell and editor view.
• Sources/ObviousSaveMDCore: document state and UTF-8 file I/O.
• Tests: Swift Testing coverage for document behavior, editor setup, and hostile file intake.
• Resources/Info.plist: app bundle metadata used by Scripts/build-app.sh.
• .github/workflows/ci.yml: GitHub Actions test workflow.
• SECURITY.md: current file-intake security notes and limitations.

Status

This is an early local macOS editor. It edits Markdown as plain text and does not include Markdown preview rendering, document sandbox entitlements, autosave, or notarized distribution packaging yet.

License

ObviousSaveMD is released under the MIT License.