Common Lispers have had the ability to write CUDA kernels (with shaders) on-the-fly with a DSL in cl-cuda for many years now. See,

https://github.com/takagi/cl-cuda

Cupy (a project in which takagi is/was actively involved) also has the ability to compile kernels in the Python REPL, but the kernel code needs to be written in C and passed in as a string (pyOpencl can do the same for OpenCL). In fact, not too many years ago, the kernels for gradient descent, max pooling etc. were all entirely in Python in Chainer. Projects like JAX take this to another level by having the ability to transform the bytecode of a restricted class of Python functions straight into CUDA kernels.

I can't speak much about Clojure/Neanderthal, but I'd advise the people to stop dissing projects they are not familiar with, least of all using silly benchmarks like the above.