Eglantine has delivered two meaningful fixes for experimental Nintendo Switch 2 emulation on PC in the space of an hour. Build 79, published October 31 at 18:38 UTC, corrects unwanted gamepad inputs. It follows build 77, released at 17:38 UTC, which targets the graphics-memory exhaustion that could make Mario Kart World display corrupted textures and crash after a few minutes.
These are specific changes with technical explanations, not simply an incremented version number. They could matter to players testing the emulator on Windows and Linux, particularly those running graphics cards with limited VRAM. But neither release is an independently verified promise of flawless racing or universal compatibility.
Build 77: Mario Kart World was filling video memory
The developers say Mario Kart World could exhaust the host GPU's memory during play. Their changelog describes failures on 8GB cards and also on 16GB cards when ASTC textures were uncompressed. Once memory was exhausted, new textures could be created without valid backing memory, producing visual garbage before a crash.
Eglantine's texture-collection thresholds were part of the problem. On some AMD configurations, a host-visible device-local heap is not extra memory; it represents the same physical VRAM. Adding heap budgets together could therefore make the emulator believe it had more usable memory than the GPU actually provided. Its texture collector then failed to run at the necessary time.
Build 77 changes that calculation to follow the main device-local heap's available budget. It refreshes those figures every 30 frames and makes its image-memory accounting more representative of actual allocations. The aim is to make texture cleanup happen before a session exhausts the GPU.
The release introduces an additional guard for a GPU with less than 12GiB of available budget. If ASTC recompression was set to Uncompressed, Eglantine can temporarily recompress Switch 2 textures to BC3 instead. The team says keeping ASTC uncompressed requires that 12GiB budget. Importantly, the fallback is now a runtime override, not a permanent edit to the player's per-game settings.
Technical users can inspect the documented diagnostic switches EDEN_NX2_KEEP_ASTC=1 and EDEN_NX2_VRAM_LIMIT_MIB. These are tools for controlled testing, not blanket recommendations to disable the new memory safeguards.
Build 79: one controller button could activate two
The build 79 release notes focus on an input bug with SDL gamepads. A mapped controller could generate both a raw joystick event and a mapped gamepad event for the same physical action. Eglantine was recording both, even though their index values meant different things.
That caused some surprisingly disruptive input combinations. On an Xbox One controller, the developers report LB also pressing Back, Start triggering a stick click, and other buttons affecting unintended inputs. Pulling the left trigger could also move the right stick vertically because the event's numeric index was being interpreted incorrectly.
The fix stops processing the duplicate mapped gamepad cases. Buttons and axes are instead driven by the joystick events whose indices match the bindings Eglantine actually stores. This is intended to prevent phantom presses and trigger movement from interfering with play.
The developers say explicitly that everything else in build 79 is identical to build 77. That attribution matters: the VRAM fix belongs to build 77, while build 79 adds the controller fix. Someone who upgrades directly to build 79 receives both changes, but they should not be presented as two improvements first introduced by build 79.
A further GPU-memory deadlock repair
Build 77 also addresses a separate synchronization problem. According to the project, allocating and mapping backing memory for sparse GPU regions while holding a mutex could create a lock-order conflict with a guest page-table lock. Under certain conditions, a host-side service thread and a guest thread could end up waiting on each other.
The code now moves allocation and mapping outside the affected mutex, tracks blocks still being backed and coordinates waiting threads using a condition variable. It also releases newly allocated mappings if their region disappears during the operation.
This is a low-level stability fix. It does not add a new game to a compatibility list, but it targets a failure mode that could freeze execution regardless of whether a game's graphics otherwise appear correct.
Where to download Eglantine build 79
The official GitHub release lists Windows archives and Linux AppImages, including variants built with profile-guided optimization (PGO). Windows instructions point to eglantine.exe for the graphical interface and eden-cli.exe for command-line operation.
Linux users must make the AppImage executable; the project specifies glibc 2.39 or later. Examples given by the maintainers include Ubuntu 24.04, Fedora 40, Debian 13 and Arch Linux.
The maintainers say their PGO versions contain the same software compiled using profiling information. The Windows PGO variant is a MinGW build with bundled DLL dependencies. Users should download only from the project's own repository and preserve their legitimate saves and settings before changing experimental builds.
Eglantine distributes emulator software, not Nintendo game files. Its release does not supply commercial ROMs, firmware or encryption keys, nor does it grant rights to download those assets from unauthorized sources.
Does this mean Mario Kart World now runs perfectly?
No. The technical release notes describe fixes for known failure modes; they are not broad performance measurements. They do not document sustained frame rates on a representative set of AMD, NVIDIA and Intel GPUs, nor do they guarantee that every track or gameplay mode survives long sessions.
For meaningful comparisons, testers should identify the exact emulator build, game update, graphics card, available VRAM, driver and rendering backend. A game reaching its title screen differs from entering a race, and a short race differs from reliable hours-long gameplay.
This also has nothing to do with a new Switch 2 console jailbreak. Eglantine runs on PCs and these updates address emulated graphics memory, synchronization and controller mappings, not an exploit for Nintendo hardware.
What to watch next
Build 79 is worth following because it combines a targeted Mario Kart World memory fix from build 77 with a concrete gamepad regression fix. The next useful evidence will be repeatable reports from lower-VRAM PCs and tests showing that controllers no longer send unintended inputs.
Until those results exist, the accurate takeaway is that Eglantine's developers have shipped repairs for documented problems—not that Switch 2 emulation is finished. Readers can check the unabridged build 77 notes and build 79 notes for the implementation details.
Image credit: The authentic, unmodified Eglantine/Eden application icon comes directly from the emulator's upstream repository, not image generation. The project copyright manifest attributes this software icon to © Eden Emulator Project under GPL-3.0-or-later.
Source date: October 31, 2026