But a C compiler is part of basically every Unix system. That matters. For example, one of the perks of my job is that I do occasionally get to play with real nice hardware (such as a Cray with a couple thousand nodes at one point). The downside of that is that the owners won't give me root access and because there are lots of other people working with it, stability of the system is more important than getting the newest software installed. Oh, and this also sometimes means restricted internet access.

So, bootstrapping matters to me, and the bootstrapping story for anything involving LLVM isn't very good (I'm actually having some problems with a language other than Rust in this regard).

Interpreters you can generally build fairly easily from source (Lua, Ruby, Python, Tcl, for example). But when it comes to compilers, bootstrapping is generally a much bigger obstacle. There are a few notable exceptions that only require a C compiler, no internet access during their build, and build in an acceptably short time:

* OCaml bootstraps from C via a bytecode interpreter, which is then used to build the native compiler. On my laptop (using four cores), I can actually do that in under a minute (two minutes if I want flambda).

* Nim compiles to C and hence builds in half a minute on the same machine from C sources.

* LuaJIT builds in a few seconds, assuming a dynamically typed language with a JIT compiler is sufficient for you.