Orbit for AI coding agents
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The numbers.

Orbit against Zed, VS Code and Cursor, measured on one Mac on 2026-10-21: MacBook Pro, Apple M3 Pro, 18 GB, macOS 27.0.1. Each app opened the same small TypeScript project (18 files, a git repository), three times after a warm-up launch; the bars are medians.
37 MB on disk. The text, the windows and the controls are the Mac's own; no browser engine inside to carry.
  1. Orbit37 MB
  2. Zed270 MB
  3. VS Code946 MB
  4. Cursor1,017 MB
623 ms to the first window. Zed is quicker here. Launched with the files in the disk cache, a project opening with it.
  1. Orbit623 ms
  2. Zed407 ms
  3. VS Code567 ms
  4. Cursor900 ms
68 MB with a project open. Every process the app owns, 15 seconds in; agents aside.
  1. Orbit68 MB
  2. Zed158 MB
  3. VS Code885 MB
  4. Cursor2,429 MB
2 processes. The app and the terminal's shell. Cursor runs 22.
  1. Orbit2
  2. Zed2
  3. VS Code11
  4. Cursor22
0.00 s of CPU in a quiet half minute. All of its processes together, with nobody touching anything.
  1. Orbit0.00 s
  2. Zed0.70 s
  3. VS Code3.69 s
  4. Cursor11.75 s

Agents aren't counted

An agent is its own program — Claude Code and Codex are CLIs Orbit starts and talks to over ACP — and it costs the same in any editor that runs it. An Orbit window opens with a chat, so the agent you used last starts with it; the numbers above leave it and everything it starts out. With it, on the same runs: 662 MB in 14 processes, of which Orbit's own share is the 68 MB above.

Cursor and VS Code ran with fresh profiles and no extensions, Zed with a fresh profile too: each as light as it gets. Orbit ran as it's installed here, with its settings, extensions and language servers.

How

  • Size on disk is the app bundle, as Finder counts it.
  • First window is the time from open -a to the first window of at least 400 × 300 on screen, polled every 5 ms. The app wasn't running, but its files were in the disk cache — what you get opening it a second time in a day, not after a restart.
  • Memory is the sum of footprint — Activity Monitor's “Memory” — over every process the app owns, 15 seconds after the window appears: those from its bundle, and everything they start (helpers, language servers, the terminal's shell, git).
  • Processes counts the same set.
  • Idle CPU is the CPU time all of them used in the next 30 seconds, with nobody touching anything.

The tool is a hundred lines of Swift; it and the project are in site/bench. Run it on your Mac — the numbers will differ, the proportions shouldn't much.

Every run

AppRunFirst windowMemoryProcessesIdle CPU
Orbit1543 ms68 MB20.01 s
Orbit2651 ms68 MB20.00 s
Orbit3623 ms68 MB20.00 s
Zed12101 ms183 MB20.78 s
Zed2407 ms158 MB20.70 s
Zed3402 ms155 MB20.65 s
VS Code1539 ms949 MB113.69 s
VS Code2567 ms885 MB114.05 s
VS Code3587 ms883 MB113.43 s
Cursor11019 ms2490 MB268.93 s
Cursor2900 ms2429 MB2232.43 s
Cursor3759 ms1719 MB1811.75 s

Versions: Orbit 0.1.0, Zed 1.24.4, VS Code 1.141.0, Cursor 3.24.12.