rsedit — All features

Speed without the baggage

• Rust file engine — Reads, search, and saves run on blocking workers so disk work stays off the UI thread.
• Quick startup — No startup indexing or network services. Syntax parsers load only when a language needs them.
• Measured locally — A macOS Apple silicon release probe reached its first 3 GiB view in 1.34 seconds from Rust entry; an open request in the running app took 132 ms. Readiness excludes process-loader time and is not a first-paint measurement.
• Focused interface — A small text editor in the spirit of Sublime Text: files, tabs, shortcuts, and the tools you use every day.

Everyday editing

• Files and folders — New, open, save, save as, save all, reload, recent files, multi-file dialogs, drag and drop, and executable path arguments. macOS Open With is supported.
• Folder panel — Resize the panel, show hidden files, and expand folders on demand. Folder choice and panel visibility restore after orderly quit; refresh entries manually.
• Tabs — Keep selections, scrolling, and undo history while the app is running. Closing the active tab returns to the most recently selected remaining tab.
• Multiple cursors — Add cursors above or below, select the next occurrence, or make a rectangular selection.
• Find and replace — Match counts, regex, case and whole-word options, plus go to line. Huge files offer whole-file literal find/replace and explicit view-only regex find/replace; go to line stays relative to the view.
• Syntax highlighting — Detect language by filename or choose it manually. Rust, JavaScript, TypeScript, Python, JSON, HTML, CSS, Markdown, SQL, shell, and more.
• Your preferences — Light and dark themes, word wrap, font size, 2/4/8-space indentation, comments, and bracket matching. Regular files also support folding.

Multi-GB files, in explicit sections

• Opening target — A disposable 3 GiB file reached its first native view within two seconds on the measured Mac. This is not a guarantee for every machine or storage device.
• Bounded reads — Files above 64 MiB, or with a physical line longer than 1 MiB, use bounded views. Files above 4 MiB start with plain text; language selection remains available. At most 256 KiB of original text reaches the editor at a time.
• Navigation — Move to the previous or next section, or jump to a byte offset. Section boundaries preserve UTF-8 characters and CRLF pairs; very long physical lines may span sections.
• Section scope — Line numbers, go to line, and selections apply to the current view. Undo/redo span views and saves. Mod+H opens view-only regex find/replace.
• Whole-file search — Mod+F opens case-sensitive literal find/replace across the file. Replace all streams into a temporary buffer with progress and is undoable; user files change only on Save. Whole-file regex replacement is not supported.
• Byte preservation — Unedited source bytes stay on disk and survive section edits byte-for-byte. Saving streams the result through a temporary file.
• Memory — Memory scales with loaded sections and edits rather than original file size. Repeated section edits, large pastes, and undo history still consume memory.
• Highlighting limits — Very long lines switch to plain text. Section boundaries can lose multiline syntax context; folding and bracket assistance are omitted.
• Measurement scope — A 3 GiB Rust-core probe measured 0.46–1.23 ms for open plus first-view read and 2.3 MiB peak RSS in a separate open-only process. These numbers exclude the native UI and cold storage; Windows/Linux runtime performance remains unverified.

Keep your work

• Hot exit — An orderly quit checkpoints open and closed buffers before closing the window, without unsaved-change questions. The window stays open if preserving the session fails.
• Reopen closed tabs — Restore up to 50 tabs with Cmd/Ctrl+Shift+T, including scratch buffers. Individual unsaved tab closes still ask before closing.
• Lazy restore — Load only the active tab on launch; other restored tabs load when selected. Tab order, active tab, primary selection, scrolling, section position, and language choice persist.
• Recovery copies — Session buffers live in the app data directory. They preserve unsaved work separately from your original files; use Save to update your file.
• Crash recovery — Checkpoints run every 30 seconds and on orderly quit. Force quit and crashes restore the last completed checkpoint; newer edits can be lost. Undo history starts fresh after restart.
• Large recovery buffers — The first checkpoint of an edited huge file streams an immutable source copy. Later checkpoints reuse it and store edits plus piece references. Copies require disk space and can take seconds.

File safety and limits

• Text formats — UTF-8, UTF-8 BOM, and LF/CRLF are supported. Binary and UTF-16 files are rejected. Large files validate each section as it is loaded.
• External changes — Size and modification time are checked around disk-backed reads, search, and saves. Saving refuses to overwrite a source changed externally. On focus, clean buffers reload and edited buffers offer recovery choices; no live file watcher is included.
• Changed large-file sources — Copy visible text to a new recovery tab before reloading, and retain the last successful checkpoint. Unseen source bytes cannot be reconstructed safely after an external change.
• Atomic replacement — Save syncs a temporary file beside the destination and then replaces it, preserving basic permissions. The operation needs disk space for the complete resulting file.
• Preservation limits — Unchanged bytes retain BOM, UTF-8, CRLF, and mixed separators outside changed ranges. Hard-link relationships, extended metadata, and ACL preservation are not guaranteed.
• Local operation — No accounts, app telemetry, extension system, language servers, or background indexing. Folder quick-open searches on request without indexing. Continuous whole-large-file scrolling and whole-file regex replacement are not supported.

Keyboard shortcuts

Mod means Cmd on macOS and Ctrl on Windows/Linux. In large-file mode, Mod+F opens whole-file literal find/replace and Mod+H opens view-only regex find/replace.

New / Open / Save

Mod+N / Mod+O / Mod+S

Open folder

Mod+Alt+O

Save As

Mod+Shift+S

Close / reopen tab

Mod+W / Mod+Shift+T

Find

Mod+F

Command palette

Mod+Shift+P

Quick-open folder files / tabs

Mod+P

View-only find/replace (huge files)

Mod+H

Next / previous tab

Ctrl+Tab / Ctrl+Shift+Tab

Undo / redo

Mod+Z / Mod+Shift+Z

Select next occurrence

Mod+D

Add cursor above / below

Mod+Alt+Up / Mod+Alt+Down

Go to line

Mod+G

Toggle comment

Mod+/

Toggle wrap

Mod+Shift+W

Font size / reset

Mod+plus / Mod+minus / Mod+0