Fast custom firmware for the GKD Pixel 2
-Forty systems, PortMaster ports, box art and RetroAchievements, from a card you can take out.
+Forty systems with their box art, PortMaster ports and RetroAchievements.
zyperos.com
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+
+ On in about 2 seconds. The stock firmware takes 30 to 40.
+ Turn it off mid-game; turn it on, and 2 seconds later you're back where you were.
+ Forty systems with their box art, PortMaster ports, RetroAchievements, and your music and videos. Free and open source.
+
- A fast, light firmware for the GKD Pixel 2 that plays your whole retro library.
- Forty systems, PortMaster ports, and your music and videos, from a card you can take out at any time.
+ 
zyperos.com · - The name · + Why ZyperOS · + From the stock OS · + Features · Compare · - Install · - Light and dark · Systems · Controls · - FAQ + FAQ · + Discord +
+ +
+ 
+ 
+ The tour, 105 seconds on zyperos.com
+
 Every system, in pixel art |
-  Or the Gallery home |
-  Your games, cover by cover |
+ Your games, cover by cover |
+  Favorites from every system |
+  Box art the handheld finds itself |
 A game's details, one button away |
-  RetroAchievements on the device |
-  The device's settings in one menu |
+ Every system, in pixel art |
+ Or the Gallery home |
+  Pick a cover, and see it first |
 Your albums and films, in MP4 |
-  Now Playing, on SELECT from anywhere |
-  Box art from three sources |
+  RetroAchievements, and Zyper cheers |
+  A quick slot for each system |
+  SELECT with a shoulder: the hotkeys |
 PortMaster with one press |
+  What fills the card |
 The battery, as time left |
- A quick slot for each system |
- SELECT with a shoulder: the hotkeys |
|
 Every button, as its pad draws it |
+ Your albums, books and films, in MP4 |
+ A game's details, one button away |
+ The device's settings in one menu |
-
-ZyperOS is named after **Zyper**, my dog, who passed away. He was quick, light on his feet and full of energy, and that is what this system tries to be.
-
-The name is also two words in one: **zippy** and **hyper**. Games start the moment you press A, the menus never make you wait, and the whole system is small enough to come up in about two seconds.
+
## Features
@@ -97,8 +152,17 @@ The name is also two words in one: **zippy** and **hyper**. Games start the mome
- **Battery care:** a battery too low to start says so and charges first; a charger plugged in while the Pixel 2 is off shows the charge and the time to full (hold POWER to start); **Getting hot** warns before the handheld slows down to cool, over a game or a port; and **MENU > Charge Limit** stops charging at 80, 85 or 90% to keep the battery young, and holds it within 2 points of the limit on the cable (78 to 80% at 80%).
- **About,** besides the version and the card, tells [the story of the name](#the-name) beside a photo of Zyper, and thanks the projects ZyperOS is built on.
- **Play Time:** how long you've played each game or console, today, this week, this month, this year or ever.
+- **A way out of anything:** hold **MENU + START** for a second and whatever runs ends, a stuck game or port included, and the home comes back. After a crash, the Pixel 2 starts on the home rather than back in the game. In the in-game menu, **X** quits from any row.
- **Continue or from the start, favorites and sorting:** A continues a game where you left it and Y starts it from the start; Y on a game's details (X) favorites it, and a heart before its name says so on its console's shelf; each console sorts by name, play time, last played or recently added.
+## The name
+
+
+
+ZyperOS is named after **Zyper**, my dog, who passed away. He was quick, light on his feet and full of energy, and that is what this system tries to be.
+
+The name is also two words in one: **zippy** and **hyper**. Games start the moment you press A, the menus never make you wait, and the whole system is small enough to come up in about two seconds.
+
## How it compares
The GKD Pixel 2 has several operating systems to choose from. This is ZyperOS beside the one it comes with and four others, from what each one's own pages, code and releases say in November 2026. ROGUE OS set the bar for this handheld, and ZyperOS set out to match it.
@@ -124,8 +188,10 @@ The GKD Pixel 2 has several operating systems to choose from. This is ZyperOS be
| **Pick a game's cover on the device** | From three sources, a big look first, the old one kept to put back | — | — | — | — | — |
| **Video previews on the shelf** | Yes | — | — | — | — | — |
| **Charge limit** | 80, 85 or 90% | — | — | — | — | — |
+| **Battery time left** | Time left, or time to full on the cable | — | — | — | — | — |
+| **A DS game's language** | Picked per game, whatever `firmware.bin` says | — | — | — | — | — |
| **Charging screen when off** | Yes | — | — | — | — | — |
-| **Boot time** | 1.6 s4 | — | — | 2.2 s4 | — | — |
+| **Boot time** | 1.6 s4, about 2 s from power on5 | 30 to 40 s from power on5 | — | 2.2 s4 | — | — |
— means none of the sources below says either way. The Pixel 2 has no Wi-Fi of its own, so on every system a Wi-Fi feature needs a USB Wi-Fi adapter. Knulli, muOS, twigUI (spruceOS) and a MinUI port run on the Pixel 2 too.
@@ -133,12 +199,13 @@ The GKD Pixel 2 has several operating systems to choose from. This is ZyperOS be
2. No count is published, so this is the systems in its own list, counted without tools, media players and ports. Hacks and regions can be entries of their own.
3. In builds made with ScreenScraper's developer key.
4. Each project's own number, and not measured the same way: ZyperOS's from the kernel's start to the home screen, on the Pixel 2 (mean of 10 starts), and TortOS's from power on to its shelf.
+5. My own count on my Pixel 2, from power on until it can be used, with the stock card it came with and with ZyperOS: the stock firmware takes over 30 seconds, usually close to 40; ZyperOS about 2.
Forty systems, PortMaster ports, and your music and videos, from a card you can take out at any time.
+On in about 2 seconds. The stock firmware takes 30 to 40. Turn it off mid-game; turn it on, and 2 seconds later you're back where you were.
- ZyperOS 1.0.2 is out for the GKD Pixel 2. +
Every game shows its real box art, found on the handheld from libretro, ScreenScraper and SteamGridDB, and a few seconds of video when you rest on it.
The stock firmware takes 30 to 40, in my test on my Pixel 2. Turn it off mid-game, and the next start puts you back where you were, 2 seconds later.
Forty systems and PortMaster's ports. Mario Kart DS keeps 60 frames a second and Super Mario 64 its 30, on the Pixel 2.
Add games, music and saves from any browser over Wi-Fi or the USB cable, and update ZyperOS the same way.
A first start that teaches every button, eight languages, light and dark, and a menu that never makes you wait.
GPL-3.0, with nothing locked behind a payment. Everyone gets the same ZyperOS.
In my test on my Pixel 2, the stock firmware takes over 30 seconds to start, usually close to 40. ZyperOS is on in about 2, and POWER in a game saves it, so the next start puts you back in that game. Beyond that, ZyperOS has what the stock column of the comparison doesn't show:
+Keep the stock card as your way back: ZyperOS goes on a second card, and swapping cards switches systems (keeping the stock card safe). Your games come over as files, each into its console's folder under Roms/.
+ZyperOS in 105 seconds, every screen drawn by the launcher itself on a sample library.
+ +The emulator stays running, so a game is up as soon as you choose it, and it picks up where you left it.
The emulator stays running, so a game is up as soon as you choose it. A picks up where you left it, and Y starts it from the start.
Animated consoles on a Spotlight or Gallery home, A to Z or by release date, and your games as a row of covers, a heart before each favorite's name.
English, 简体中文, Español, Português (Brasil), Français, Deutsch, 日本語 and Italiano, from the menus and the in-game menu to the charging screen, the boot screen and the File Transfer page. Pick one on the first start or in MENU > Language.
Zyper says hello in each language until you pick yours, teaches each button and shows where it is on the Pixel 2, then asks for the theme, the home screen, the button sounds and the menu music.
An empty card opens on the two ways to add games, USB or Wi-Fi, one button each. Zyper cheers when they arrive.
MENU > Scraper asks libretro with no account, ScreenScraper with a free one in builds that carry its developer pair, and SteamGridDB with your own key. Renamed ROMs match by checksum.
X on a game, then Cover and Video: every box, 3D box, title screen and screenshot the three sources offer, named with where it comes from. A shows it big first, and the cover it replaces is kept to put back.
X on a game, then Cover and Video: every box, 3D box, title screen and screenshot the three sources offer, named with where it comes from. A shows it big first, and the cover it replaces is kept to put back. Its video snap is there too, to watch, download, replace or delete.
Rest on a game for a second and its cover turns into a few seconds of the game, from ScreenScraper. A play mark says which games have one.
X on a game, then Delete Game: it asks first, then takes the game with its saves, states, cover and video, and the shelf moves on. A file another game still uses stays, and so does a BIOS set like neogeo.zip.
MENU > Storage shows what fills the card in one bar, then every system by size and each system's games largest first. Music, Videos and Audiobooks open their albums, films and books, and X sorts any list by size, A to Z or last played. It suggests what can go: art of games no longer there, and save states of games not played for a year.
Ten free 8-bit tracks behind the menus, never over a game. Your own in Roms/BGM play instead.
Move games, music and saves from any browser, behind a PIN. With no Wi-Fi around, the handheld makes its own network for your phone. It keeps going while you play, and shows the time left.
A charge limit of 80, 85 or 90%, a charging screen while the handheld is off, and a warning before a low battery or heat gets in the way. The corner can show the time left at once, or the time to full on the cable, instead of the percentage, and says so when the charge is on hold or done.
Plug in a computer and the Pixel 2 asks first: charge only, or open USB File Transfer.
Plug in a computer and the Pixel 2 asks first: charge only, or open USB File Transfer. Developer Mode, hidden on About behind L2 + R2 held for five seconds, brings up SSH over the cable.
Over Wi-Fi, only what changed, signed, with Roll Back. Without Wi-Fi, the File Transfer page brings it over the USB cable.
Dreamcast, PlayStation and Game Boy Color rumble games shake the Pixel 2. Its four side lights show the battery charging and running low, the volume and brightness as you change them, a climb when files or covers finish, and a sparkle for an achievement. MENU > Side Lights turns each on or off.
8-bit and handheld systems run at lower clocks, measured to keep every frame, and the battery lasts longer.
Hold SELECT and press R1 to save a state, L1 to load it, into the slot you pick for each system. SELECT on its own still belongs to the game.
SELECT + R2 runs a game at 1.5x, 2x or 3x, and SELECT + L2 steps back down. X and Y are turbo A and B.
Hold MENU + START for a second and whatever runs ends, a stuck game or port included, and the home comes back. In the in-game menu, X quits from any row.
Controls in the in-game menu shows what each button does in that game, on its system: its own buttons, the PlayStation's as their shapes, turbo, the hotkeys, the N64's C buttons and the DS's stylus.
Beard in light, Salt & Pepper in dark. MENU > Appearance chooses Light, Dark or Auto, and the first start asks.
ZyperOS 1.0.2 is out for the GKD Pixel 2, released in November 2026. Each release has the card image and ZyperOS Installer for macOS, Windows and Linux.
-Or download the card image, the .img.xz file, and write it with any disk image writer, such as Raspberry Pi Imager. New versions come later with System Update, over Wi-Fi or the USB cable, or with the installer's Update, which keeps a card's games, music and saves.
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Forty systems, PortMaster ports, box art and RetroAchievements, from a card you can take out.
+Forty systems with their box art, PortMaster ports and RetroAchievements.
zyperos.com
