Batocera Download 2026: v43.1 in 12 Steps, 15 Mins

There is no checkout page. That is the first thing to understand about downloading Batocera, and it is the thing every third-rate tutorial buries under a hedge of affiliate buttons and "recommended hardware" you do not need. Batocera Linux is free — not free-trial, not freemium, not free-with-an-asterisk. It is an open-source retro-gaming distribution maintained by volunteers, it costs exactly nothing, and the current stable release as of this writing is 43.1, published on 30 May 2026. You can grab it from batocera.org/download and never see a price tag.

What follows is the honest version: a prerequisites list that states the real hardware floor, a 12-step install that explains why each step exists rather than just barking commands, and a troubleshooting table for when the flash inevitably goes sideways on somebody's decade-old ThinkPad. We will also point out the two or three places the internet lies to you — the "3-minute download" filehosts, the 16 GB storage trap, and the tutorial farms that still tell you to run dd like it is 2015. One more thing up front, because it saves grief later: Batocera ships no games and no BIOS files. You supply those yourself, and we will get to what that means legally and practically. The download is the OS. Everything that makes it a games console, you bring.

What "Free" Actually Buys You

People searching "batocera download" fall into two camps: those who assume free software must be worse, and those who assume there is a catch. Neither is right. Batocera is free the way the Linux kernel is free, because it is largely the Linux kernel plus a curated stack of emulators and a front end. Let us define the terms precisely so you know what you are getting and what, if anything, is expected of you in return.

No download cost, one licence caveat

Batocera costs nothing to download, run, or redistribute. There is no licence key, no account wall, no telemetry-for-access bargain. The source code lives on GitHub at github.com/batocera-linux/batocera.linux under open-source licences — it is a full Linux distribution assembled from GPL and permissively licensed components, so "free" here means both zero-cost and freely modifiable. The one caveat worth stating plainly: the Batocera name, logo, and theme artwork are published under Creative Commons Attribution-NonCommercial-ShareAlike, © 2016–2026. That licence governs the branding, not your right to run the operating system. You may install Batocera on as many machines as you own. What you may not do is sell "Batocera-branded" retro boxes off the back of that artwork and pass it off as your own product.

If you want to give the project money anyway, GitHub Sponsors exists. It is entirely optional and buys you nothing except continued releases and a warm feeling. The practical upshot is blunt: anyone charging you for a "Batocera download" is running a grift, and anyone selling a preloaded microSD stuffed with ROMs is mostly selling you copyright infringement plus a markup. The software was always free; the value they added was the felony.

The version ladder: 36 to 43.1

Batocera releases on a rolling-but-numbered cadence, so the version number tells you roughly how current your install is. Here is the recent ladder, which matters because half the "tutorials" online are pinned to a build two years stale:

You can confirm every one of those dates against the project's own current and previous releases page and the line-by-line changelog on GitHub. Do that. It takes thirty seconds and inoculates you against the SEO farms that invent version numbers wholesale.

Why 43.1 and not 43

Version 43, codenamed "Glasswing," was the substantial release. Its headline was the migration to a Wayland session running the LabWC compositor on the x86_64-v3 image, replacing the older X-based stack and cleaning up graphics handling on modern integrated GPUs. That is the kind of change that improves everything and breaks a few things. Three weeks later, 43.1 arrived specifically to fix EmulationStation emulation regressions that shipped in 43, and it rolled libretro MAME forward to 0.285 while it was at it.

The lesson generalises. When two builds sit this close together, install the point release, not the round number. The .0 is where the brave live and the bug reports get filed; the .1 is where those reports get answered. Download 43.1.

Prerequisites: Hardware & Software

Batocera's marketing — such as it is, being a volunteer project with no marketing — leans on "runs on anything." That is true in the charitable sense and misleading in the practical one. It will boot on a potato. Whether it will run Dreamcast at full speed on that potato is a different question. Here is the floor, and the difference between the floor and the ceiling.

Hardware floor: RAM and storage

The absolute minimum is 1 GB of RAM; the realistic recommendation is 2 GB or more, because the heavier libretro cores and any standalone emulator worth running will thrash a 1 GB system the moment you leave the 8-bit era. For storage, the minimum is 16 GB and the recommendation is 32 GB or larger — and this is not a soft recommendation you can ignore. On 16 GB media, Batocera disables the automatic updater entirely, because there is no headroom to stage an update image alongside the running system. Flash to 16 GB and you have signed up to upgrade by hand forever. Spend the extra two dollars on a 32 GB stick. This is the single most common self-inflicted wound in the whole process, and we will return to it in the pitfalls section because people keep doing it.

For the CPU: any x86_64 chip from roughly the last decade will do. To run the modern x86_64-v3 image — the one with the Wayland/LabWC compositor — you want a processor that supports the v3 microarchitecture level, meaning Intel Haswell (2013) or newer, or AMD Excavator/Zen or newer. Integrated Intel or AMD graphics are fine and generally preferred for compatibility; NVIDIA works but occasionally sulks. If you are choosing a machine specifically for this, the wiki's choose a desktop computer page is the reference, and a cheap mini PC like a Beelink S12-class box is the sweet spot the 2026 builds are tuned around.

The flashing software you need

You need a tool that can write a compressed .img.gz to a block device and, ideally, verify the write afterward. The Batocera wiki explicitly recommends Raspberry Pi Imager (1.8 or newer) or USBImager. balenaEtcher also works and verifies by default. All three decompress the gzip on the fly, so you do not extract the image first. The wiki just as explicitly says dd is "not recommended" — not because it fails, but because a fat-fingered of= silently overwrites the wrong disk and there is no undo, no confirmation, no mercy. If you know exactly what you are doing, dd is fine; if you are asking a tutorial how to download Batocera, use a GUI imager with guardrails.

Beyond the imager you will want: a USB stick or SSD of 32 GB or more, a USB keyboard for the first boot (before your controller is mapped), and a controller Batocera recognises — virtually any modern Xbox, PlayStation, or 8BitDo pad qualifies. If your ambitions run to handhelds rather than a mini PC, note that the same x86_64-v3 image targets x86 handhelds too; our Switch 2 versus Steam Deck breakdown covers where those devices actually land on price and performance if you are still deciding what to flash it onto.

What Batocera is NOT

Three quick myths, dispatched deadpan. First, Batocera is not RetroPie. They are separate projects with different philosophies; RetroPie is a layer you add to Raspberry Pi OS, Batocera is a standalone immutable distro. If you are weighing them for a PC build specifically, our piece on how RetroPie's x86 image has been frozen at v4.8 since 2022 explains why the comparison is less symmetrical than the forums pretend. Second, Batocera is not an emulator — it is a distribution that bundles the RetroArch/libretro cores and a pile of standalone emulators behind one front end. If you want to understand or tune the cores it ships, our guide to installing and tuning RetroArch cores is the companion read. Third, Batocera is not illegal software. The operating system is entirely legal to download and run. What you copy into the roms/ folder is your responsibility and yours alone.

Which Image Do You Actually Need?

The download page offers more than one image, and picking wrong is the difference between a working console and a fifteen-minute detour into confusion. The good news is the decision tree is short.

x86_64 vs x86_64-v3

For desktops, laptops, and Intel-based Apple computers there are two x86 builds. The plain x86_64 image is the compatibility build for older processors. The x86_64-v3 image is the 2026 build carrying the Wayland session and LabWC compositor from the Glasswing release, and it requires a CPU that implements the v3 microarchitecture level (AVX2 and friends), which in practice means anything Haswell-era or newer. If your CPU supports v3 — and any machine bought since about 2014 does — take the v3 image. You get better performance and the modern compositor. Only fall back to plain x86_64 if you are reviving genuinely ancient hardware that refuses to boot the v3 build.

Raspberry Pi and handheld builds

Batocera also publishes images for the Raspberry Pi family and a long list of ARM single-board computers and handhelds. These are not interchangeable with the x86 images — an ARM board needs its ARM build, and a Pi 4 image will not boot a Pi 5. If you are targeting a specific board, find its exact entry on the download page rather than grabbing the generic one. For x86-based handhelds in the Steam Deck / GPD / AYN class, you are back to the x86_64-v3 image; there is no separate "handheld" x86 build, the v3 image is it.

Decoding the filename

The desktop and laptop download is named along the lines of batocera-x86_64-43.1-xxx.img.gz, and the pattern decodes cleanly: batocera (the distro), x86_64 (the architecture — the v3 build reads x86_64_v3), 43.1 (the version), then a build stamp, then .img.gz. The .img is a raw disk image; the .gz means it is gzip-compressed, which is why it downloads at roughly 2.5 GB rather than the eight-plus gigabytes it occupies once written. A competent imager expands it during the write, so leave it compressed. If a download hands you a bare .img you extracted yourself, that is fine too, just larger.

Downloading & Verifying the Image

Now the actual download, plus the part nobody does and everybody should: verifying it before you commit it to a disk.

The one URL that matters

The canonical source is batocera.org/download, with the raw images also browsable at batocera.org/images/download/. Select your architecture, click, and wait. At roughly 2.5 GB the download takes a few minutes on any normal broadband connection — not "three minutes guaranteed," just "a few minutes, depending on your line and the mirror's mood." That is the entire download step. There is no installer to run, no account to create, no email to confirm. You are downloading a disk image, and the next section turns it into a bootable drive.

Mirrors: the good, the sketchy

If the main site is slow, the project runs a legitimate mirror at mirrors.o2switch.fr/batocera/, which also hosts the beta channel and the boot.tar.xz files used for manual upgrades — we will use that later. That mirror is fine. Use it.

What is not fine, and what the deadpan half of this article exists to warn you about, is the ecosystem of random filehosts that circulate on forums and low-effort "12-step 2026 tutorial" sites, advertising their own re-uploaded image with a promised "3-minute download speed." Do not use them. You cannot verify what you are flashing, a retro-OS image conveniently ships with default root credentials, and an image is a wonderful place to hide something you would rather not run with root. The rule is simple: the image comes from batocera.org or the o2switch mirror, full stop. If a tutorial is steering you toward its own filehost link instead of the official page, that tutorial is monetising your trust, and you should close the tab.

Verifying the download

A corrupt .img.gz is a special kind of infuriating because it flashes without complaint and then fails to boot with no explanation — a black screen, a boot loop, or a kernel panic that tells you nothing. Verifying takes ten seconds and prevents an hour of head-scratching. First sanity-check the file size (it should be in the neighbourhood of 2.5 GB, not 4 KB of HTML error page). Then check the SHA-256 hash against the value published beside the download:

$ sha256sum batocera-x86_64-43.1-20260530.img.gz
9f2c...compare-against-the-published-hash...a41b  batocera-x86_64-43.1-20260530.img.gz

# Windows (PowerShell):
PS> Get-FileHash .\batocera-x86_64-43.1-20260530.img.gz -Algorithm SHA256

If the hash matches, the download is intact. If it does not, delete it and download again — do not flash it "just to see." Imagers like balenaEtcher and Raspberry Pi Imager also perform a read-back verification after writing, which catches corruption introduced by the flash itself; leave that verification enabled even though it doubles the write time. Belt and braces. This is a two-minute insurance policy against the most common failure in the entire process.

The 12-Step Install

Here is the spine of the tutorial: twelve numbered steps from bare hardware to a running, game-loaded console. Each step carries its rationale, because a step you understand is a step you can debug when it misbehaves. The whole sequence, download excluded, runs about fifteen minutes on decent hardware. The authoritative reference for the install proper is the wiki's install Batocera page; this is the opinionated, annotated version of it.

1. Confirm your target meets the floor. Verify 2 GB+ RAM and, critically, a 32 GB+ write target. Rationale: 16 GB media permanently disables auto-updates and undersized RAM stalls anything past the 16-bit era. Fixing this after the fact means reflashing from scratch, so fix it now.
2. Pick the correct architecture image. For any CPU from 2014 onward, take x86_64-v3; for genuinely old hardware, plain x86_64; for a Pi or ARM board, that board's specific image. Rationale: the wrong architecture will not boot, and the wrong x86 variant costs you the Wayland compositor and its performance gains.
3. Download only from batocera.org. Use the official page or the o2switch mirror — never a third-party filehost. Rationale: integrity and trust; you are about to run this with root privileges on your network.
4. Verify the download. Check the ~2.5 GB size and match the SHA-256 hash before doing anything else. Rationale: a corrupt image flashes cleanly and then fails silently, and you will blame everything except the file.
5. Install a flashing tool. Raspberry Pi Imager, USBImager, or balenaEtcher — not dd unless you are certain. Rationale: these decompress the .gz, verify the write, and refuse to overwrite your system disk without a fight.
6. Write the image to your 32 GB+ drive. Select the Batocera .img.gz as source, select the USB stick or SSD as target, and write. Rationale: this erases the target completely — triple-check you selected the stick and not the drive with your photos on it. There is no recycle bin here.
7. Set the boot order and disable Secure Boot in UEFI. Enter your firmware setup, move the Batocera drive to the top of the boot order, and turn Secure Boot off. Rationale: Batocera's bootloader is unsigned; Secure Boot will refuse to load it, and the machine will fall straight through to whatever else is installed.
8. Boot from the media and let userdata auto-expand. Power on, boot Batocera, and wait through the first-boot partition resize without interrupting it. Rationale: on first boot Batocera grows its data partition to fill the whole drive; yank power mid-resize and you may corrupt the filesystem before you have even started.
9. Verify video output and map a controller. Confirm the resolution and audio are sane, then use the keyboard to open the menu and run the controller mapping. Rationale: EmulationStation needs at least one input device mapped before it is usable, and confirming video now saves you diagnosing a "dead" console that is merely on the wrong HDMI mode.
10. Connect to the network. Plug in Ethernet or configure Wi-Fi from the network menu. Rationale: this brings the SMB share online so you can copy games from another machine, and enables updates and scraping.
11. Copy ROMs and BIOS into the share. Place games under share/roms/[system] and BIOS files under share/bios/. Rationale: emulators locate content by exact folder and, for BIOS, by exact filename and MD5 — a system with no valid ROMs stays hidden from the menu entirely.
12. Update gamelists, then update Batocera. Refresh the gamelists so new titles appear, and if you are not already on 43.1, run the updater. Rationale: the gamelist refresh surfaces what you just copied, and the 43.1 point release fixes the EmulationStation emulation bugs that shipped in 43.

That is the whole install. If a step misbehaves, the troubleshooting table further down maps symptoms to causes. But nine times out of ten, the twelve steps above run start-to-finish without incident, and the tenth time it is the 16 GB card from step one coming back to bite.

First Boot: Expected Output

Knowing what a healthy first boot looks like is half of diagnosing an unhealthy one. Here is what you should see, and what you can check from a terminal to confirm the install took.

The expansion sequence

The first boot is slower than every subsequent one, and that is by design. After the kernel and splash, Batocera resizes the userdata partition to consume the entire drive, then reboots itself once before dropping you into EmulationStation. This takes a minute or two on a 32 GB stick and longer on a large SSD. Do not power off during this. If you interrupt the resize you can land in a half-expanded filesystem that boots but silently runs out of space later. Let it finish. When EmulationStation appears with its system carousel, the expansion is done.

Expected console output

Once you are on the network you can confirm the install from another machine over SSH (default credentials root / linux — documented on the wiki's SSH access page, and yes, you should change that password). A healthy system looks like this:

$ ssh root@batocera.local
# uname -a
Linux BATOCERA 6.x.x-batocera #1 SMP x86_64 GNU/Linux

# df -h /userdata
Filesystem      Size  Used Avail Use% Mounted on
/dev/sda2        28G  1.2G   27G   5% /userdata

The kernel string confirms a 64-bit Batocera build. The df line is the one that matters: if /userdata reports the full capacity of your drive (28 GB free on a 32 GB stick, allowing for overhead), the auto-expansion completed. If it instead shows a suspiciously small partition — a couple of gigabytes — the resize was interrupted and you should reflash. Note also that the root filesystem is read-only by design; only /userdata is writable, which is why every configuration change lands there.

Resolution and audio sanity check

EmulationStation defaults to a sensible resolution, but "sensible" and "what your TV actually accepts" occasionally disagree, and the result is a black screen that reads as a dead install. If you see nothing after the splash, the cause is almost always a video-mode mismatch rather than a failed boot. The fix is to set an explicit mode — either through the menu once you can see it, or by editing global.videomode in the config, which we cover in the final section. For audio, open the sound settings and select the correct output device (HDMI versus analogue versus a USB DAC); a game running with a silent soundtrack is usually pointed at the wrong sink, not broken. Confirm both now, while the system is empty and fast, rather than mid-game later.

Adding ROMs & BIOS Files

The OS is installed; now you make it a console. This is the step Batocera cannot legally do for you, and the step where folder discipline separates a working library from a menu full of mysteriously-missing systems. The authoritative reference is the wiki's add games and BIOS page.

The network share method

The clean way to move files is over the network share Batocera exposes automatically. From Windows or macOS it appears as \\BATOCERA\share; from Linux, mount smb://BATOCERA.local/share. If name resolution is being difficult, substitute the console's IP address for the hostname. You do not need credentials for the share itself — it is open on the local network for convenience, which is another reason not to expose a Batocera box to the wider internet. The share is the front door to the writable /userdata partition, organised into predictable folders:

\\BATOCERA\share\
  bios\
  roms\
    snes\
    megadrive\
    n64\
    psx\
  saves\
  screenshots\
  system\        (contains batocera.conf)

Where ROMs and BIOS go

ROMs go in roms/[shortname], where the shortname is Batocera's system identifier — snes, megadrive, n64, psx, and so on. Drop a Super Nintendo ROM into roms/snes/ and it appears under the SNES system; drop it in the wrong folder and it appears nowhere. BIOS files go in bios/, and here precision is non-negotiable: many emulators require a BIOS with an exact filename and a matching MD5 checksum, and a renamed or slightly-wrong BIOS is treated as absent. The definitive list of which systems need which BIOS, with the expected names and hashes, is the libretro BIOS reference — keep it open while you populate the folder. Batocera also has a built-in BIOS checker in its menus that flags missing or mismatched files, which is faster than debugging "why won't PlayStation launch" the hard way.

Refreshing the gamelist

After copying files, tell EmulationStation to look again. Press START, open GAME SETTINGS, and run UPDATE GAMELISTS; your new titles appear, and you can then scrape metadata and box art if you want the menu to look like something. A word on where those ROMs should come from, since we promised to know the law: the cleanest path is dumping cartridges you already own, which is exactly what hardware like the Retrode is for — our 12-step guide to dumping cartridges with the Retrode walks through turning a shelf of carts into a legal ROM library. Batocera hands you the machine; sourcing the games responsibly is the part that keeps this a hobby rather than a hearing.

Common Pitfalls & Their Fixes

Six failure modes account for the overwhelming majority of "help, it doesn't work" posts. Learn them here and skip the forum.

Pitfalls one and two: storage and corrupt images

Pitfall 1 — the 16 GB trap. You flashed to a 16 GB card because it was in the drawer, and now the auto-updater is greyed out. This is not a bug; Batocera disables auto-updates below the storage threshold because it cannot stage an update image safely. Fix: reflash to a 32 GB or larger drive, or resign yourself to manual upgrades forever (covered in Advanced Tips). There is no config toggle that conjures the missing space.

Pitfall 2 — the silent corrupt flash. The image downloaded, flashed without error, and the machine will not boot — black screen or boot loop. Nine times in ten the .img.gz was corrupt on download or the write failed unverified. Fix: re-download from the official source, confirm the SHA-256, flash with verification enabled, and if it still fails, try a different USB stick — cheap flash media dies quietly.

Pitfalls three and four: firmware and architecture

Pitfall 3 — it boots into Windows instead. The flash worked but the machine ignores it. Fix: enter UEFI setup, disable Secure Boot (Batocera's loader is unsigned and Secure Boot blocks it outright), and move the Batocera drive to the top of the boot order. On some firmware you must also enable booting from USB explicitly.

Pitfall 4 — wrong architecture image. You grabbed x86_64-v3 for a pre-2013 CPU that does not support the v3 level, and it boot-loops; or you grabbed plain x86_64 on modern hardware and wonder where the Wayland compositor went. Fix: match the image to the CPU — v3 for anything Haswell-era or newer, plain x86_64 for older, and the board-specific image for ARM.

Pitfalls five and six: 3DS ROMs and vanished emulators

Pitfall 5 — 3DS games refuse to launch. Version 43 tightened the Nintendo 3DS handling: encrypted CIA/CCI dumps no longer run, and you must supply decrypted ROMs. The .3ds format is supported again, but hardware shaders default to off, so re-enable them if performance is rough. Fix: decrypt your dumps and check the shader setting. While we are in this territory, note that DraStic, the Nintendo DS emulator, was removed in v43 because it is closed-source — if your DS games vanished after upgrading, that is why, and the replacement path is melonDS or DeSmuME. TheXTech, similarly, now needs 1.3.7-or-newer assets.

Pitfall 6 — a system needs BIOS and won't say so nicely. Games load but immediately fail, or the whole system is missing, and the cause is a BIOS file in the wrong folder or under the wrong name. Fix: put BIOS in bios/, match the exact filename and MD5 from the libretro reference, and run Batocera's built-in BIOS checker to confirm before you go hunting elsewhere.

Troubleshooting Table

Symptom-to-cause-to-fix, for the failures that survive the pitfalls above. Work top to bottom; the cheapest fixes are listed first.

Advanced Tips

Once the basics work, Batocera rewards a little terminal literacy. Here is where the config-file crowd pulls ahead of the menu-only crowd.

SSH access and the filesystem

SSH in with root / linux and you get the full picture. Remember the layout: the root filesystem is read-only and the only writable area is /userdata, which is why every persistent setting lives there. The master configuration file is /userdata/system/batocera.conf — it is the single source of truth for system behaviour, and editing it directly is faster and more precise than clicking through menus, especially for settings the menus do not expose. Change your password immediately (passwd), because default credentials plus an open SMB share is a bad combination on any network you share with other people.

# confirm the running version and free space
$ ssh root@batocera.local
# df -h /userdata
# nano /userdata/system/batocera.conf   # edit config directly
# batocera-save-overlay                 # persist system-level changes
# reboot                                # apply

Manual and offline upgrades

If you are stuck on 16 GB media, running an offline machine, or you simply prefer control over your updates, you upgrade by hand. Download the appropriate boot.tar.xz from the o2switch mirror, place it, and let Batocera's upgrade routine swap the boot payload on the next reboot. The full, exact procedure — including which file goes where and how to invoke the manual upgrade — is documented on the wiki's upgrade manually page, and you should follow it verbatim rather than improvising, because putting the wrong boot.tar.xz in place can leave you unbootable. This is the escape hatch that makes even the 16 GB trap survivable; it is just tedious enough that buying the bigger card was always the smarter move.

Overclocking and performance flags

Performance tuning in Batocera happens mostly through per-system config overrides rather than global switches. You can pin a specific core to a system (n64.core=mupen64plus_next), force a video mode per system, toggle integer scaling, and disable the more expensive niceties — shaders, rewind, run-ahead — on hardware that cannot afford them. Rewind in particular is a quiet performance tax; turning it off frequently rescues a borderline PS1 or N64 experience. Because Batocera's cores are the libretro cores, everything you learn about tuning them transfers directly; our RetroArch cores tuning guide covers the core-level knobs (latency, shaders, driver selection) that Batocera surfaces through these config keys. Start conservative, change one variable at a time, and keep a note of what you changed — the fastest way to an unbootable emulator is five simultaneous "optimisations."

A Complete Working batocera.conf

To close, here is a complete, sane starting configuration you can adapt. It is trimmed for readability but every key is real and documented; the goal is a system that networks, updates, and runs the common systems well out of the gate.

The batocera.conf

## /userdata/system/batocera.conf — trimmed working example
## Every key here maps to a documented setting; edit, save, reboot.

## --- System ---
system.hostname=BATOCERA
system.language=en_US
system.kblayout=us
system.timezone=Europe/Paris

## --- Updates (requires 32GB+ media) ---
updates.enabled=1
updates.type=stable

## --- Network ---
wifi.enabled=1
wifi.ssid=YourNetwork
wifi.key=YourPassword
controllers.bluetooth.enabled=1

## --- Audio / Video ---
audio.volume=90
audio.device=auto
global.videomode=default

## --- Global emulator defaults ---
global.smooth=1
global.rewind=0
global.integerscale=1
global.ratio=auto
global.shaderset=none
global.retroachievements=0
global.retroachievements.username=
global.retroachievements.password=
global.retroachievements.hardcore=0
global.netplay=0
global.netplay.nickname=Player1

## --- Per-system overrides ---
nes.core=fceumm
snes.core=snes9x
megadrive.core=genesisplusgx
n64.core=mupen64plus_next
n64.videomode=default
psx.core=swanstation
psx.ratio=4/3
## 3DS (v43+): supply DECRYPTED roms; hardware shaders off by default
3ds.videomode=default

How to apply it

Two ways in. Over the network, open the system/ folder in the SMB share and edit batocera.conf there. Over SSH, edit /userdata/system/batocera.conf directly with nano. Either way, save the file and reboot; Batocera reads the config at boot and applies it. Keys mirror the on-screen menu options closely, so if you are unsure what a key does, find it in the menu first, then set it here for repeatability. Keep a copy of your working config somewhere off the device — when you reflash for the next release, dropping your saved batocera.conf back into place restores your entire setup in seconds.

That is the whole arc: a free 2.5 GB download, a verified flash, twelve steps to a running console, and a config file you own outright. No checkout page, no licence key, no catch — just an open-source distribution, a wiki that tells the truth, and whatever games you can legally bring to it. Download 43.1, verify it, and go build the machine.