One 15-second clip of the mouse sliding across the screen edge took an open-source KVM from a sub-thousand-follower account to 900 stars

In 2026, on an October 19 afternoon, UK indie developer Toby Kalkman posted a vertical video on his TikTok account @kalkmancode. A MacBook sat next to a Windows PC. He pushed the pointer past the right edge of the Mac screen, the edge slowly lit up, and the pointer crossed over and landed on the PC's screen. The caption read: "Push through a screen edge or corner and Beamer takes your mouse and keyboard to the other computer. MacBook notch too." The account had under a thousand followers at the time. By 11-06 the video had 490k views, 30k likes, and 12k saves. Beamer is his free, open-source "software KVM" that shares one keyboard and mouse across Mac, Windows, and Linux. The repo was 41 days old with 899 stars. This piece covers where those stars came from, and how to try the same approach for your own open-source project.

What it is

A desktop utility: several computers on the same LAN. Install Beamer, enter a six-digit pairing code, and push the mouse past a screen edge to reach another machine. The keyboard follows, and so does the clipboard. On Mac, Cmd becomes Ctrl automatically on Windows. You can also double-tap the right Option key to jump across. If you lose the pointer, shake the mouse and it comes back. No account, no cable, no hardware box. Written in Python, GPL-3.0.

The idea isn't new. Synergy has been around for over twenty years, and its open-source core is now called Deskflow. Barrier, Input Leap, and lan-mouse are the same kind of tool. What Beamer adds is polish: the edge glows as you cross, a "pressure" damping setting prevents accidental switches, you can cross through the MacBook notch, and a short animation plays around the pointer on arrival. There are several effect styles and color themes. The README's hero image is the GIF of pushing through an edge.

Where the stars came from: not Hacker News, TikTok

The timeline is clean (star counts from GitHub daily snapshots):

Both jumps landed one or two days after a video went out. Hacker News has no mention of it, X has had almost no discussion in the last two months, and there's no press coverage. The Chinese sites, Vietnamese blogs, and Instagram repost accounts that say "comment beamer and I'll DM you the link" all came after the jumps, as long-tail spread.

Every one of the author's videos follows the same formula: a real desk, one action, and a line written for ordinary people. "No cable. No KVM box. No account." And "On your phone? Save this for your desk." That last line is written for people scrolling on their phones: you can't use it right now, so save it and install it when you're back at your computer. 490k views turned into 12k saves, which suggests the line worked.

Conversion is worth checking too: 490k views brought in roughly 100 stars (est.). Most viewers are ordinary users with "one Mac and one PC on the desk." They'll download, but they don't necessarily have a GitHub account. Stars are only the visible slice; download counts weren't available this time.

What the comments are saying

On the 490k-view video, the most-liked comment is "Vibecoded detected" (1658 likes), and third is "u can just tell its vibecoded too" (840 likes). Some defend it: "'But it's vibecoded' translating: I don't like anything that's actually cool if it's made by ai" (156 likes). Most of the other top comments plug competitors: "nobody knows about powertoys.." (89), "Synergy. Been around for decades." (68), "Mouse without borders" (49), "or just use the classic free and open source app Deskflow" (11).

The skepticism didn't stop the stars, and it kept the comment section busy. The most useful comment has only 2 likes: "I've been using Deskflow to connect my PC and Mac until the macOS 27 beta broke it, so I had to switch to the paid Synergy. Since this one is open source, I'll try it." The need is real, and the old options are failing.

The author kept up with the wave: from 10-23 to 11-03 they shipped 1.5.12 to 1.5.19 eight versions. Nearly every changelog says "from user reports," fixing things like the Windows installer, dead keys, and Wayland, the kinds of problems you only hit after installing.

Why it took off

1. Big companies left a gap, and old open source is falling behind. Apple's Universal Control only works between Apple devices; Microsoft's Mouse Without Borders only works between Windows machines; Logitech Flow requires Logitech mice. A desk with a Mac and a PC side by side falls right into the gap. Barrier is basically unmaintained, Input Leap hasn't had a push in a year, Synergy charges money, and Deskflow's setup is geared toward engineers.
2. The product itself is the visual. Edge glows, notch crossings, landing animations: none of it is engineering-necessary, but it's exactly what lets a keyboard-and-mouse sharing tool make a 15-second video. Functionally it's close to Deskflow; the difference is that it's instantly understandable.
3. The author films it themselves and writes for ordinary people. Instead of "cross-platform input forwarding built on Python," it says "your desk just lost a keyboard."
4. Repost accounts amplify it. Vertical-video accounts that specialize in "good stuff on GitHub," like github.signals, brought the single-day high of +161 in one post.

The author also has a plan for monetization: the desktop app stays free forever, and a paid phone companion, Beamer Pocket, is sold separately (terms published 10-19; whether it's listed hasn't been verified). But for readers chasing stars, that isn't the point.

Who it's competing with

The one to watch is TwinDesk: it started two weeks after Beamer and already has 4 times Beamer's star count. These projects were built independently, so there's no clear copying, but it shows the "good-looking cross-platform keyboard and mouse sharing" spot already has four or five entrants in a single month. Beamer itself has also added drag-and-drop to its 1.6 preview.

If it were you

The takeaway: the method is worth learning, but the spot is getting crowded. Beamer shows that an individual developer with under a thousand followers can use self-filmed vertical video to push an open-source desktop tool to several hundred or thousand stars, with no HN and no reputation needed. But the "cross-platform keyboard and mouse sharing" category now has contemporaries like TwinDesk, with 4 times the stars. Building another one will struggle to stand out.

Who it suits: indie developers who build small desktop tools, are willing to appear on camera to film their desk, and can ship a new version every two or three days.

Who it doesn't suit: products whose effect can't be "seen" in 15 seconds (CLI tools, libraries, backend services); people who plan to post once on HN and wait for stars; and anyone who can't handle "vibecoded" being the first comment.

How to do it: follow the formula to find the next spot: a feature that a big company only built between its own devices, plus an unmaintained or hard-to-use old open-source option. Examples: AirDrop-style file transfer between Mac and Windows, a cross-platform universal clipboard history, or switching one external monitor between a Mac and a PC. (These are inferred directions; before starting, search GitHub to see whether someone shipped one this month.) The core action needs visual feedback so it makes sense even without narration; put a GIF of that action as the first image in the README. Zero configuration: pairing with a short code is ten times friendlier than IP addresses.

How to get users: a week before the repo goes up, post teasers on TikTok / Instagram / YouTube Shorts asking something like "Anyone else running X and Y side by side?" After launch, post every two or three days, each video covering one action only, with copy written for ordinary people and a closing line like "On your phone? Save this for your desk." Proactively send the demo video and repo link to GitHub repost accounts like github.signals. In the days when it's gaining traction, ship a patch every day and write the problems users report into the changelog.

When this window was open: this playbook relies on "good GitHub stuff" being a fresh content category on short-video platforms, with repost accounts still hunting for material. Estimated to work if you start before the first half of 2027 (inferred), so the window is still open.

Signs you're reading it wrong: if your work gets hundreds of thousands of views but only a few dozen stars, this category's audience isn't on GitHub, and you should look at downloads rather than stars. If feature-heavier projects like TwinDesk keep overtaking, looks alone aren't enough; you need to ship the feature users want most at launch.