I built a native cross-platform editor that opens 10GB files instantly (free beta)

smozumezume — Wed, 14 Oct 2026 07:00:12 +0000

I just opened a free public beta of Zume Editor, a native text / code / hex editor for Windows, macOS and Linux, written from scratch in C++. I'd love your feedback — especially on large files and the all‑in‑one workflow.

Download: https://smolt-stage.com/home/en/download.html
Help: https://zume-editor-dev.github.io/zume-editor-help/
Source of truth for releases: https://github.com/zume-editor-dev/zume-editor-releases

The itch I was scratching

My day used to mean juggling a pile of tools: a viewer for gigantic logs, a hex editor, a Git client, an SFTP client, a DB client, a diff tool. Each one slow to start, and several of them choke on big files.

I wanted one lightweight native app that does all of it, keeps a shared UI and a single undo, and stays responsive even on multi‑gigabyte files. That's Zume.

Design principles:

Native performance first — instant startup, no heavy runtime.
Huge files are first‑class — never load a 10GB file fully into RAM.
All editing is a testable command/service, not UI code — the engine is the product.

Large files, for real

The engine is a memory‑mapped piece table: it opens, searches, edits and saves 10GB+ files without reading them into memory. First view is near‑instant, scrolling stays smooth, and search streams through the file instead of blocking the UI. This is the part I'd most like you to try to break.

What's in the one app

Hex editor — offset / ASCII / EBCDIC columns, byte find & replace, undo shared with the text view.
Git client — stage/commit, branches, a log graph, diffs, conflict resolution, fetch / pull / push.
Terminal, SSH & remote editing — a built‑in terminal, an SSH shell, and remote files over SFTP / FTP / FTPS.
Database tools, a two‑pane diff & merge, CSV grid editing.
Format conversion (encodings, line endings, geo data…), a CLI (zume-cli), and an MCP server for AI agents.
Plus the everyday stuff: syntax highlighting, code folding, outline, multi‑caret, column mode, search/replace, split view, session restore.

Hex editor	Git client

Diff & merge	Terminal / SSH

Rendering is native on each OS (Direct2D/DirectWrite on Windows, Core Text on macOS, GTK4/Pango on Linux).

Try it

Grab a build from the download page or the Releases:

Windows 10/11 (x64) — portable ZIP (no installer; unzip and run)
macOS (Apple Silicon) — DMG, signed & notarized (launches without warnings)
Linux (x86_64) — AppImage / DEB / RPM

Verify downloads against SHA256SUMS.txt. On Windows the beta isn't code‑signed yet, so SmartScreen may warn — choose More info → Run anyway (the stable build will be signed).

About the beta (being upfront)

This is an early public beta. All features are free to use until 2027‑03‑31 — a long runway on purpose. After that, the stable release will be a subscription; one license will cover all three platforms. I'd rather be transparent now than surprise anyone later, and beta builds will carry a clear notice.

If you hit a bug or have a feature request, please open an issue — it genuinely shapes the 1.0:
➡️ https://github.com/zume-editor-dev/zume-editor-help/issues
(OS, app version, steps to reproduce; on Windows the log is at %LOCALAPPDATA%\ZumeEditor\logs\zume-editor.log.)

Thanks

If you work with big logs, binaries, remote servers, or just want text/hex/Git/SSH/DB in one fast native window, I'd love for you to give it a spin and tell me what breaks.

Download: https://smolt-stage.com/home/en/download.html
Help: https://zume-editor-dev.github.io/zume-editor-help/
Feedback: https://github.com/zume-editor-dev/zume-editor-help/issues