The Windows kyber_launcher.exe approach under Wine/Proton has two
unfixable problems on Linux: Wine's cmd.exe crashes with STATUS_ACCESS_VIOLATION
on the long EA OAuth URL, and EA's auth callback uses the eadesktop://
URI scheme which has no Linux handler.
The correct solution is the native Linux port AppImage maintained at
github.com/simonlinuxcraft/kyber-linuxport-unofficial. It bundles Maxima
(open-source EA Desktop replacement) and handles OAuth natively — no shims,
no watchers, no per-Proton-update maintenance.
Script now: fetches latest release from GitHub API, downloads AppImage,
installs desktop entry and ~/.local/bin/kyber symlink.
README: add Gaming scripts section documenting Kyber setup, private server
hosting with bots, requirements, and what does not work.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01D8ckUJQtj1pH8jtAddBDZs
After extensive testing, Wine/Proton loads cmd.exe exclusively from
Proton's own installation (files/lib/wine/x86_64-windows/cmd.exe).
Replacing the prefix system32 copy, IFEO registry keys, WINEDLLOVERRIDES,
and Wine DllOverrides registry entries all have no effect — Proton's copy
always takes precedence.
The working fix: compile a tiny shim (GetCommandLineA scan for http URLs,
write to C:\kyber_oauth_url.txt, ExitProcess(0)) and replace Proton's
cmd.exe directly, backing up the original as cmd.exe.bak. The script
detects size (shim ~9KB vs real cmd.exe ~1.2MB) to avoid double-replacing.
Note for users: re-run setup-kyber-linux.sh after any Proton Experimental
update since Steam restores the original cmd.exe on update.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01D8ckUJQtj1pH8jtAddBDZs
system.reg values use \\ for one backslash, so C:\shim\kyber_cmd.exe
must be written as C:\\shim\\kyber_cmd.exe. The previous script wrote
C:\\\\shim\\\\kyber_cmd.exe (4 backslashes = two literal backslashes),
which Wine couldn't resolve.
Also detect when the shim slot contains Wine's cmd.exe (122231 bytes)
left behind by a failed earlier attempt, and recompile automatically.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01D8ckUJQtj1pH8jtAddBDZs
Proton's prefix-setup phase overwrites system32/cmd.exe on every game
launch, breaking the previous approach of placing a shim there. Switch to
Windows Image File Execution Options (IFEO): the shim is compiled to
drive_c/shim/kyber_cmd.exe (Proton never touches that directory) and the
IFEO Debugger key is written to system.reg so Wine intercepts cmd.exe at
CreateProcess time without touching the filesystem binary.
Also fix the wine64 path used for winetricks: correct path is
files/lib/wine/x86_64-unix/wine64 not files/bin/wine64.
The shim is simplified to scan all args for any http URL (IFEO passes the
debuggee path as an extra arg, so the /c start pattern match was fragile).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01D8ckUJQtj1pH8jtAddBDZs
Steam sets STEAM_COMPAT_DATA_PATH to compatdata/<appid> when launching
a non-Steam shortcut. The prefix was named 'kyber' so Steam was launching
into an empty prefix, causing immediate exit. Change KYBER_COMPAT_ID to
match KYBER_APPID (9900000001) and migrate any existing 'kyber' prefix.
Also handle cmd.exe being a symlink: resolve and copy the real file as
cmd-real.exe, then remove the symlink before writing the shim so we only
affect the Kyber prefix and not Proton globally.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01D8ckUJQtj1pH8jtAddBDZs
Large stack array WCHAR[4096] triggered a stack probe (__chkstk_ms)
unavailable in -nostdlib builds. Fix: heap-allocate the pass-through
command line buffer, and add -mno-stack-arg-probe as a safety net.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01D8ckUJQtj1pH8jtAddBDZs
_wcsicmp is a CRT function unavailable with -nostdlib/-ffreestanding.
Replace with CompareStringOrdinal from kernel32 (always available).
Also fix step numbering (1-2 were still labeled /5 instead of /7),
and remove 2>/dev/null from compile so errors are visible if it fails.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01D8ckUJQtj1pH8jtAddBDZs
- Python shortcut script now checks for existing 'Kyber Launcher' entry
and exits early instead of appending a duplicate on each re-run
- Use sudo apt-get directly for mingw-w64 install so the password prompt
works (previous chained || approach suppressed the interactive prompt)
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01D8ckUJQtj1pH8jtAddBDZs
Wine's cmd.exe crashes (0xC0000005) when Kyber calls cmd /c start with
the EA auth URL, on native Linux Steam just as in Wolf. Fix:
1. Compile a minimal cmd shim with mingw-w64 (auto-installed if missing).
The shim intercepts cmd /c start <http url>, writes the URL to
C:\kyber_oauth_url.txt, and exits 0. All other cmd invocations are
passed through to the backed-up cmd-real.exe.
Installed into the Kyber prefix's system32 only — does not affect
other games or Proton globally.
2. Install a watcher script (~/.local/bin/kyber-oauth-watcher.sh) that
polls for the URL file and calls xdg-open to open it in the system
browser. Registered as a systemd user service so it starts on login.
Login flow: Kyber → cmd shim → URL file → watcher → xdg-open → browser
→ EA login → redirect to 127.0.0.1:PORT → Kyber loopback catches code.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01D8ckUJQtj1pH8jtAddBDZs
On re-run the installer was trying to overwrite locked files in an existing
prefix, causing repeated Access Denied dialogs. Now check for Kyber.exe
first and skip the installer entirely if it's found.
Also kill any leftover Wine/Proton processes before a fresh install to
avoid file-lock conflicts, and move Windows path resolution to after the
installer/skip decision so it always runs regardless of path taken.
Default fallback path updated to match Kyber's actual install location:
C:\Program Files (x86)\KYBER Launcher\
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01D8ckUJQtj1pH8jtAddBDZs
If shortcuts.vdf exists but is not writable, attempt chmod 644 before
writing. If that also fails, print a clear instruction and skip the
shortcut step rather than crashing with a Python traceback.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01D8ckUJQtj1pH8jtAddBDZs
The Evergreen bootstrapper (linkid=2124703) requires a second download from
inside the Wine process, which fails in Proton. Switch to the standalone
offline installer (linkid=2135547, ~150 MB) which installs without any
Wine-internal network calls.
Also prefer winetricks if installed — it uses a local cache, handles the
WINEPREFIX env correctly, and is the most reliable method. Fall back to
the standalone download if winetricks is not available.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01D8ckUJQtj1pH8jtAddBDZs
Instead of erroring when the installer is missing, attempt to fetch it
automatically: first scrape kyber.gg for a direct .exe link, then fall
back to a known CDN path. If download fails, print the manual instruction
and exit cleanly.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01D8ckUJQtj1pH8jtAddBDZs
Kyber uses a PKCE loopback OAuth flow (Maxima): it starts a temporary
HTTP server on 127.0.0.1 and calls cmd /c start to open the EA auth URL
in the system browser. On native Linux, Wine's cmd passes http:// URLs
to xdg-open, which works fine inside Steam's single bwrap layer.
Remove the incorrect claim that WebView2 intercepts qrc:// URIs and is
the only path to completing login. Keep the WebView2 runtime install
(harmless, prevents in-app render errors) but clarify it is not the
login mechanism.
Update end-of-script instructions to describe what the user will actually
see: browser opens EA page, redirects to 127.0.0.1:PORT, tab shows OK or
connection-refused (normal), login completes in Kyber. Add troubleshooting
notes for the two real failure modes: xdg-open not reaching the desktop
(headless/no DISPLAY), and login timeout (loopback server expired).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01D8ckUJQtj1pH8jtAddBDZs
Runs Kyber outside Wolf so its embedded WebView2 can initialize without
nested-bwrap blocking CLONE_NEWUSER. Builds the Wine prefix, ensures the
WebView2 Evergreen runtime is installed (the component that intercepts EA's
qrc:// OAuth redirect), registers Kyber as a non-Steam shortcut forced to
Proton Experimental, and notes the Steam Remote Play path for headless boxes.
No fake cmd.exe / Firefox scaffolding needed here.
Co-Authored-By: Claude <noreply@anthropic.com>
Claude