Every copy,
pressed into wax.
The Windows clipboard holds one thing, and forgets it the moment you copy the next. Keros keeps all of it on your PC, and finds any of it in the time it takes to type three letters.
I
The clipboard forgets.
Windows does keep a short history (Win+V), and for many people it is enough. For everyone who copies all day, it runs out quickly. ¹
Windows clipboard history
Your last 25 copies, until you restart.
Keros
Every copy since the day you installed it. Search tested on 300,000. ²
| Keros | Windows clipboard history | |
|---|---|---|
| Kept | Everything, for as long as you choose | The last 25 copies |
| After a restart | All still there | Cleared, except pinned items |
| Kinds | Text, rich text, images, files, links, colours | Text, HTML, images; up to 4 MB each |
| Searchable | Everything, as you type, forgiving typos and accents | At most the last 25 copies |
| Organising | Named, coloured pinboards | Pinned items |
| Where it lives | On this PC only; no network access at all | On this PC; optional sync via a Microsoft account |
II
It remembers quickly.
16.7 ms
From Ctrl+Shift+V to the strip on screen: sooner than a 60 Hz monitor draws its next frame. ³
5.3 ms
From a keystroke to painted results, with 90,000 clips in the history. ³
0.000 %
CPU while it waits in the tray. Nothing wakes it but a copy or your shortcut. ³
11 MB
Memory at rest, with the whole history on hand. ³
III
Made of Rust, and very little else.
Keros is one native Windows program written in Rust. There is no web browser inside it, no runtime to install and no garbage collector to pause it halfway through a keystroke.
It sleeps until Windows tells it something changed: a copy, or your shortcut. It keeps no timers and polls for nothing, which is why it sits at zero in Task Manager.
Search is built for this one job. The history is scanned newest-first from a memory-mapped index with SIMD byte search, and trigram filters skip whole blocks that cannot match.
The strip is drawn on the CPU. A GPU renderer would have loaded 27 to 88 MB of graphics driver before showing a single card. And it copies what you copied out of the clipboard in under 4 ms, then lets go, so no other app waits on it.
IV
Nothing you copy ever leaves your PC.
No network
No account, no cloud. Our tests fail if the running app opens a single TCP or UDP endpoint.
No passwords
Copies marked private are never read. Password managers are excluded from the start.
Your rules
Pause, exclude apps, keep a day or forever, erase in one step.
Off the record
Optionally hidden from screenshots, recordings and screen sharing.
V · Forthcoming
A memory your agents can ask.
Keros will speak MCP, so Claude Code and other MCP clients can look things up in your history: the error from an hour ago, the link from this morning. It runs on your PC over stdio, stays off until you turn it on, and asks before each tool is used.
› Find the panic I copied this morning and fix it.
keros · search_history("panicked", since: today)
thread 'main' panicked at src/main.rs:7:5:
called `Option::unwrap()` on a `None` value
Windows Terminal · 09:14
Found it: line 7 unwraps a missing config value…
Keros for Windows 11
No account, no sign-up. Unzip, run install.cmd, press Ctrl+Shift+V.
Download Keros 0.1.0Zip, 7.2 MB · Windows 11, 64-bit
SHA-256 10df7bd7b3a17790f91764a7d379d425a1708663dff2d4692ff7fef7c63372e4
Keros is not code-signed yet, so Windows may say it does not recognise the app. Before extracting, right-click the zip, choose Properties and tick Unblock; or, when warned, choose More info, then Run anyway. Then run install.cmd. The README in the zip has the details.