Comment by badsectoracula

Well, if you don't put too much emphasis on the "hand" part of "handheld", Steam Deck is basically a PC running Linux and you can program it in any language you want.

As a bonus you can gain some muscle by carrying it around.

Alternatively, some of Anbernic's and other similar manufacturers of "retro handhelds"'s machines run plain Linux (usually derived from OpenDingux for MIPS-based devices, but most newer stuff are ported to ARM) with a simple launcher. I have one of the older MIPS-based devices running OpenDingux (GCW Zero from ~2013)[0] and you can use SDL and C/C++ (or Free Pascal in my case). Anbernic RG350 is basically a remake of it (same hardware, just better screen) and there are some variations at a software level (running the same or a similar MIPS CPU). Other devices are based on ARM (IIRC the devices ending in 1 - like RG351/RG351M/RG351P/etc - use ARM with an OS derived from OpenDingux). Note that some use Android, though they also use a different naming scheme (and they mention it).

Sadly Android-based devices are the most common and since they are largely used for emulators, the manufacturers rarely post full tech specs but there are dedicated communities and YouTube channels from where you can find what exactly OS they run and with what architecture.

But all that said, Steam Deck might be the simplest choice (though not the lightest, both in terms of weight and price).

[0] https://img.itch.zone/aW1hZ2UvNjM4NTE4LzQ3MDk2MTguanBn/origi...