Linux & SteamOS

This document records the runtime library assumptions, GLibC version requirements, fallback guidance, and the minimum and recommended system requirements for the Conversation Simulator Linux depot on Steam.

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Installer formats

Two Linux artifacts are produced by the CI release build:

Format	File	Use case
AppImage	ConversationSimulator_<ver>_amd64.AppImage	Portable — runs on any compatible x86_64 Linux without installation. Recommended for Steam Deck and Flatpak-style installs.
Debian package	conversation-simulator_<ver>_amd64.deb	Ubuntu 22.04+ and Debian 12+. Installs to /usr/bin/ with system-managed runtime dependencies.

The Steam depot ships the AppImage as the primary artifact. The .deb is available as a GitHub release asset for users who prefer system packages.

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GLibC version requirements

The C standard library (glibc) is the one shared library that is not bundled inside the AppImage — it must be present on the target system at a version equal to or newer than what was used on the build machine.

Artifact	Build machine	Minimum glibc on target
AppImage	Ubuntu 22.04 LTS (CI runner)	≥ 2.35
.deb	Ubuntu 22.04 LTS (CI runner)	≥ 2.35

Distribution compatibility (AppImage)

Distribution	Shipped glibc	Compatible
Ubuntu 22.04 LTS	2.35	Yes (exact match)
Ubuntu 24.04 LTS	2.39	Yes
Debian 12 (Bookworm)	2.36	Yes
Fedora 38+	2.37	Yes
Arch Linux (rolling)	2.38+	Yes
SteamOS 3.x (Arch-based)	2.37+	Yes
Ubuntu 20.04 LTS	2.31	No — upgrade required
Debian 11 (Bullseye)	2.31	No — upgrade required

Rationale: Ubuntu 22.04 LTS is the minimum supported distribution because the Tauri 2 WebKitGTK 4.1 binding (libwebkit2gtk-4.1) is not packaged in Ubuntu 20.04 or Debian 11 repositories. Extending support to older releases would require a custom build toolchain (e.g. a Docker image based on Debian 11 with backported WebKitGTK) — deferred to a post-launch milestone if demand warrants it.

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Runtime library requirements

AppImage

The AppImage bundles most user-space dependencies, including:

• WebKitGTK 4.1 (libwebkit2gtk-4.1.so) — web view engine
• GTK 3 (libgtk-3.so) — window chrome
• libayatana-appindicator3 — system tray icon support
• librsvg2 — SVG icon rendering
• glib2, gio, gobject — GLib base libraries

The AppImage does not bundle:

• glibc / libgcc (must be ≥ 2.35 on host)
• libX11 / libXext / libXrender / libXcursor (X11 display server, or Wayland via XWayland) — must be present on host
• FUSE 2 (libfuse.so.2) — required to mount the AppImage at runtime

FUSE note: On systems where FUSE 2 is not available (e.g. Ubuntu 22.04 ships FUSE 3 by default), run the AppImage with --appimage-extract-and-run to bypass FUSE mounting and extract to a temporary directory instead:

./ConversationSimulator.AppImage --appimage-extract-and-run

Alternatively, install FUSE 2: sudo apt-get install libfuse2

Debian package (.deb)

The .deb declares the following Depends: entries (set by the Tauri bundler):

libwebkit2gtk-4.1-0, libgtk-3-0, libayatana-appindicator3-1, librsvg2-2

Install these on Ubuntu 22.04 before installing the .deb:

sudo apt-get install -y \
  libwebkit2gtk-4.1-0 \
  libgtk-3-0 \
  libayatana-appindicator3-1 \
  librsvg2-2

Microphone (voice input)

Voice input requires xdg-desktop-portal and a running PipeWire or PulseAudio session. On headless or minimal desktop environments, microphone access may silently fail; text-only input mode works without audio hardware.

# Install xdg-desktop-portal on Ubuntu
sudo apt-get install -y xdg-desktop-portal xdg-desktop-portal-gtk

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SteamOS 3.x / Steam Deck

SteamOS 3.x is based on Arch Linux and ships with glibc 2.37+, satisfying the ≥ 2.35 requirement. The AppImage runs without modification.

Steam Deck hardware profile

Component	Spec
CPU	AMD Zen 2, 4-core / 8-thread, 2.4–3.5 GHz
RAM	16 GB LPDDR5 (shared with GPU)
GPU	AMD RDNA 2, 8 CUs, 1.0–1.6 GHz
VRAM	Shared from RAM pool (1–8 GB configurable)
Storage	64 GB eMMC / 256 GB NVMe / 512 GB NVMe
Screen	1280×800 (LCD model) / 1280×800 OLED
Input	Gamepad buttons, dual trackpads, gyro, touchscreen

Installation on Steam Deck

Via the Steam library (after depot upload):

1. Install from the Steam library entry — no terminal required.
2. On first launch the Model Manager wizard appears — download the recommended starter model (Qwen3 4B Q4_K_M, ≈ 2.6 GB).

Manual AppImage install for testing (Desktop Mode):

# In Desktop Mode, open Konsole:
chmod +x ConversationSimulator_*.AppImage
./ConversationSimulator_*.AppImage

To add as a non-Steam game for Gaming Mode launch:

1. Open Steam in Desktop Mode → Add a game → Add a Non-Steam Game.
2. Browse to the AppImage and select it.
3. Set Launch Options: (empty for default)
4. Switch to Gaming Mode and launch from the library.

Steam Deck verification checklist

Complete all items on a physical Steam Deck running SteamOS 3.x in Gaming Mode before the Stage 4 gate (G4-02) can be declared PASS. This checklist extends the general QA matrix in docs/QA_STEAM_PLATFORM_MATRIX.md.

• App launches in Gaming Mode from the Steam library without extra setup.
• Home screen, scenario picker, and Model Manager are fully navigable with the controller alone (D-pad, A/B/X/Y, left stick, right trackpad).
• On-screen keyboard appears automatically when any text input field is focused.
• All text is readable at 1280×800 without zooming or horizontal scrolling.
• No required action is hidden behind a mouse-only hover state.
• Offline smoke test passes under SteamOS 3.x (no outbound network during play).
• Steam overlay (Shift+Tab) opens and closes without breaking the current session.
• Push-to-talk key (if using voice) does not conflict with the Steam overlay binding.
• Battery draw during a text session is documented (target: < 15 W average).
• App exits cleanly and returns to the Steam library home screen.

Performance expectations on Steam Deck (Starter tier)

Metric	Target
App cold-start to home screen	≤ 10 s
Model load (Qwen3 4B Q4_K_M, first load)	≤ 90 s
First-token latency during text session	≤ 30 s
Battery draw during text session	< 15 W average

The Steam Deck GPU can run the Qwen3 4B Q4_K_M model with partial GPU offload. Set the number of GPU layers in the Model Manager settings to maximise performance. CPU-only inference is slower but fully functional.

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Minimum and recommended system requirements (Steam store page)

These are the values for the Linux section of the Steam store page.

Minimum

OS	Ubuntu 22.04 LTS or equivalent (glibc 2.35+, x86-64)
Processor	64-bit x86 processor, 4 cores, 2.0 GHz
Memory	8 GB RAM
Graphics	Any GPU or CPU with integrated graphics
Storage	2 GB available (app) + 3–6 GB for a starter model
Additional notes	Text-only play mode; voice input requires PipeWire or PulseAudio.

Recommended

OS	Ubuntu 22.04 LTS / Ubuntu 24.04 LTS / SteamOS 3.x (x86-64)
Processor	64-bit x86 processor, 6+ cores, 3.0 GHz
Memory	16 GB RAM
Graphics	GPU with 4 GB VRAM (NVIDIA RTX 2060 / AMD RX 6600 or better)
Storage	2 GB available (app) + 6–10 GB for recommended models
Additional notes	GPU acceleration significantly reduces inference latency. Microphone recommended for voice input mode.

Steam Deck

Compatibility	Steam Deck Verified (target; requires Valve review)
Notes	All official packs playable in text-only mode. Voice input available in Desktop Mode via microphone dongle.

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Fallback guidance for older distributions

If a player’s system does not meet the glibc 2.35 minimum:

1. Upgrade the distribution. Ubuntu 22.04 LTS has free upgrade paths from 20.04 via do-release-upgrade.

2. Run in a container. A Podman or Docker container based on Ubuntu 22.04 can host the AppImage with full library access. This is a developer option, not a supported player workflow.

3. Build from source. Players comfortable with Rust/Node/Python toolchains can build directly from the GitHub repository on their own distro. See docs/platform-notes.md and scripts/setup.sh.

Conversation Simulator does not ship a “legacy” build targeting older distributions in v1. If demand for older glibc compatibility is confirmed post-launch, a Debian 11 / Ubuntu 20.04 compatible build can be explored as a Stage 5 follow-on using an older build toolchain (linuxdeploy / appimagetool with glibc 2.31 base image).

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References

• platform-notes.md — Linux build prerequisites and dev environment
• QA_STEAM_PLATFORM_MATRIX.md — full manual and automated QA test matrix
• release-checklist.md — release smoke steps and CI gate list
• publishing/STEAM_DEPOT_CONTENTS.md — depot content policy
• scripts/build-linux.sh — local Linux build command
• scripts/depot-audit.sh — pre-upload depot content audit