Helio

Stream a computer's desktop and its games to another computer, inside one post-quantum WireGuard tunnel.

• Best tested: a Mac as the client, streaming a Windows host with an NVIDIA GPU and SudoVDA (the test setup).
• Install: download for macOS, Windows or Linux, Homebrew, or build from source.
• Latency: glass to glass.
• What to trust: how it's built and verified, and its known limitations.

Helio is the app: it plays your other computers, and with hosting on (a switch, off until you turn it on) it lets them play this one, through Helio Host, the host. Both run on macOS, Windows and Linux.

• Moonlight-class streaming: HEVC or H.264, hardware encode and decode, HDR and YUV 4:4:4, loss repaired by reference invalidation, frame pacing at the client display's exact rate, stereo to 7.1 sound, controllers with rumble. At 3024x1890, 120 fps and 100 Mbit/s it showed 115.6 fps, against 110.0 for Moonlight + Apollo (a fork of Sunshine with the same video path) on the same machines (benchmarks).
• Post-quantum: every packet travels in pq-boringtun (WireGuard with ML-KEM-768), and pairing is a hybrid SPAKE2 + ML-KEM PIN exchange.
• A virtual display at the client's exact mode on Windows, macOS and Linux (GNOME and KDE under Wayland) hosts, so nothing is scaled or letterboxed. On Windows, turning hosting on installs its driver (SudoVDA) and the controllers' (ViGEmBus).
• From anywhere, without port forwarding: hosts are found through sealed records on the BitTorrent DHT, and NATs are punched from both sides, with one exception.
• The clipboard, both ways: text, images, files and folders.
• Permissions per device, as Apollo has them: whether it may see the screen, use the keyboard, mouse or controllers, copy and paste each way, start apps, take over or watch agents (docs/usage.md).
• AI agents can use your hosts as clients of their own — from Helio, or from any MCP client — held to rules the host enforces (docs/ai-agents.md).

Getting started

1. Install Helio on both computers, the one to stream and the one you sit at (the host, Helio Host, comes inside it): download it for macOS, Windows or Linux from helio.mihaicristian.dev, on a Mac with Homebrew (brew tap mihaicristianfarcas/helio https://github.com/mihaicristianfarcas/helio, then brew install --cask helio), or build it from source.
2. On the host, turn hosting on in Helio (setup asks, or Settings → Hosting). On the other computer open Helio, click the host, and type the PIN it shows into the host's Helio (This computer → Devices).
3. Click the host again to stream. Ctrl+Alt+Shift+Q ends the stream (usage). While hosting is on, Helio's icon in the menu bar or the taskbar's notification area says what the host is doing; Helio says when there is an update.

Status

	Client	Host
macOS 14+	Helio.app: the best-tested client	Helio Host, inside Helio.app: works; stereo, or 5.1/7.1 with a surround output (macOS); no controllers
Windows 10/11	Helio.exe: works; less tested than macOS	Helio Host, a Windows service: the best-tested host (best with an NVIDIA GPU; without one, H.264 in software; turning hosting on installs SudoVDA for the virtual display, on x64 PCs)
Linux	works under X11 and Wayland; tested in a container	works under X11 and Wayland; a virtual display on GNOME and KDE, elsewhere the screen as it is, scaled; no controllers

What is verified and what is not, and how: docs/verification.md. Feature by feature against Moonlight + Sunshine: docs/parity.md.

Known limitations

• No phone, tablet or TV clients. Helio is for desktops: macOS, Windows and Linux.
• The Linux downloads are for Ubuntu 24.04 on x86_64 and the distributions built on it. Elsewhere, build from source.
• Windows hosts encode in hardware only on NVIDIA. On any other GPU they encode H.264 in software, with no HEVC, AV1, HDR or 4:4:4 (Windows).
• Linux hosts have a virtual display only on GNOME and KDE under Wayland. Under X11 and on other Wayland desktops they stream the screen as it is, scaled to the client (Linux).
• No controllers on a macOS or Linux host. Only Windows hosts take them (macOS, Linux).
• SmartScreen may stop the Windows installer. Helio is signed, but SmartScreen also asks for a reputation, which a signature does not give: choose More info, check the publisher, then Run anyway (what it should say).
• No relay. When both sides are behind symmetric NAT, punching through fails and nothing relays the stream: forward UDP 47800 to the host on its router (networking).

This is the beginning of the README. Read the rest at the original. Read the full README ↗