FirmMux 3DS

FirmMux 3DS
General
Author	nextcode4u
Type	Utilities
Version	1.0.4-beta8
License	Mixed
Last Updated	2026/03/18
Links
Download
Website
Source

FirmMux is a unified front‑end for CTR, TWL, System Menu, Homebrew, and RetroArch‑backed systems including: Atari 2600/5200/7800, ColecoVision, Amstrad CPC, GB/GBC, GBA, Genesis, Game Gear, Intellivision, Sord M5, NES, Neo Geo Pocket, PokeMini, SG‑1000, Master System, SNES, TurboGrafx‑16, WonderSwan, Arcade/CPS1/CPS2/CPS3, Neo Geo/Neo Geo CD, C64/C128/VIC‑20/Plus4/PET, PSX, Virtual Boy, Lynx, Jaguar, DOS, PC‑98, ScummVM, Quake, Uzebox, TIC‑80, WASM‑4, and LowRes NX.

Documentation

See the docs/ folder for setup and backend details: https://github.com/nextcode4u/FirmMux/tree/main/docs

• docs/SD Layout.md
• docs/RetroArch Emulators.md
• docs/NDS Options.md
• docs/PC Setup.md
• docs/Themes.md
• docs/Usage.md
• docs/Known Issues.md
• docs/ROM Organizer (PowerShell).md
• docs/Cover Art Sync.md

State persistence uses atomic writes with deferred idle saves to avoid launch-time stalls.

Widescreen notes and options: https://wiki.ds-homebrew.com/ds-index/rtcom?tab=forwarders

Screenshots

Changelog

v1.0.4-beta8

• Fixed clipped 92x92 cover previews while keeping them readable.
• Added date display to the status bar.
• Fixed NDS title-data wrapping/newline overlap.
• Fixed row text vertical alignment for tabs and lists.
• Simplified theme opacity behavior so background visibility no longer globally washes out the UI.
• Backgrounds now render at full opacity.
• Added per-element alpha controls for theme tuning.
• Restored theme asset support and documented the supported asset keys, formats, and recommended sizes.
• Added a repo-side themes/test_assets reference theme for asset testing.
• Fixed theme debug menu toggle selection.
• Switched RetroArch source maintenance to the tracked fork workflow.

v1.0.4-beta7

• Commits included in this release:
  • Add FirmMux updater app and docs updates
  • ui: confirm cache clear and harden toast wrapping/centering
  • pathfile: add per-system toggle and model-aware defaults
  • perf: memoize cover preview selection without stack-heavy key buffer
  • fix: guard option/menu indices during rapid state changes
  • fix: tighten shutdown cleanup for audio and transient buffers
  • harden: validate path formatting and reject truncation in launch flows
  • fix: harden runtime/cover flow failure handling

v1.0.4-beta6

• Commits included in this release:
  • Harden service init/exit lifecycle and cleanup flow
  • Harden state/theme/emulator/rules file loading safely
  • Fix icon texture leak on allocation failure
  • Fix cover preview crash when browsing emulator tabs
  • Reduce runtime cache memory footprint with 3-slot LRU
  • Add external themes with custom fonts and update bundled theme YAMLs
  • Fix NDS launch on autoboot by requiring HOME init first
  • Fix cover preview stability and expand boxart sync system coverage

v1.0.3-beta5

• Commits included in this release:
  • Remove duplicate CIA toolchain links from README
  • Refine CIA setup-helper flow, update docs, and remove boot B-skip logic
  • Ignore bundled BGM credit sidecar file
  • Ignore Windows ADS Zone.Identifier sidecar files
  • Add CIA build pipeline and update FirmMux banner/BGM assets
  • Fix 3DS HOME init flow and system menu behavior
  • Stage standalone pathfile package in PC setup and document it
  • Add standalone pathfile routing and New 3DS-only heavy system gating

v1.0.0-beta5

• Commits included in this release:
  • Ignore bundled BGM credit sidecar file
  • Ignore Windows ADS Zone.Identifier sidecar files
  • Add CIA build pipeline and update FirmMux banner/BGM assets
  • Fix 3DS HOME init flow and system menu behavior
  • Stage standalone pathfile package in PC setup and document it
  • Add standalone pathfile routing and New 3DS-only heavy system gating

v1.0.0-beta4

• Commits included in this release:
  • Stage standalone pathfile package in PC setup and document it
  • Add standalone pathfile routing and New 3DS-only heavy system gating

v1.0.0-beta3

• Commits included in this release:
  • Set default emulator tabs and update docs
  • Docs: sync SD layout, RetroArch staging, and persistence behavior
  • Stabilize state persistence, remove boot debug, and update ROM/docs layout
  • Add GBA system support and ship gba ROM folder
  • Move setup flow to PC installer and align health checks
  • covers: add SD boxart sync tool and emulator preview cache rendering
  • tools: unify release flow with canonical SD asset publish
  • Document NDS dependency links (NTR Forwarder, NTR Launcher, YANBF)
  • Remove release_notes.md
  • Fix target ID parsing and harden config reload stability

v1.0.0-beta2

• UI/theme pipeline polish and stability fixes.
• RetroArch backend flow and options improvements.
• NDS options/cheat flow iteration and docs updates.
• Additional quality-of-life fixes (toasts, list behavior, theme fallback/background handling).

v1.0.0-beta1

• Pure RetroArch 3DSX backend integration with firm handoff (sd:/3ds/emulators/launch.json) and core resolution.
• Custom FirmMux RetroArch build that boots directly into the selected core + ROM.
• Emulator system tabs with enable/disable, folder mapping, and robust missing/empty folder handling.
• Background picker (top/bottom) + background visibility control.
• Updated SD layout and documentation for RetroArch dependencies and build steps.

v0.1.0-alpha2

• This update focuses on theming, launcher selection updates, and UI polish for the alpha.
• Highlights
  • Theme system with a theme picker (Options → Themes...) and per-theme layout/spacing.
  • New color themes: default, amber, cobalt, ember, epoxy_resin, glacier, graphite, sage.
  • Epoxy Resin theme includes asset-based backgrounds and sprite icon.
  • NDS launcher auto-select uses product code CTR-P-FMBP (Select NDS launcher).
  • System info panel and status bar refinements.

v0.1.0-alpha1

• This is the first public alpha build of FirmMux. It is focused on CTR/TWL browsing and handoff, not emulation.
• Highlights
  • Config-driven targets (System Menu, 3DS Titles, Homebrew, NDS Titles).
  • NDS browser with Sprite/Title Data toggle and cached banner previews.
  • DSiWare (00048004) titles supported in the 3DS list with banner preview.
  • Homebrew launching via hb:ldr.
  • NDS launching via FirmMuxBootstrapLauncher (launch.txt handoff).
  • Top status bar (time, Wi-Fi, battery) and System Info panel on Return to HOME.

External links

• GitHub - https://github.com/nextcode4u/FirmMux