On Windows, I got it working again with current Context (20180404) and current luatex from win32tex
(1.07 development ID 6686)

On linux-armhf I did a fresh "./first-setup.sh --engine=luatex" and got:

mtx-context | ConTeXt Process Management 1.02
mtx-context |
mtx-context | main context file: /usr/local/context/tex/texmf-context/tex/context/base/mkiv/context.mkiv
mtx-context | current version: 2018.09.30 19:32

and:

This is LuaTeX, Version 1.09.0 (TeX Live 2019/dev)

The LuaTeX team is Hans Hagen, Hartmut Henkel, Taco Hoekwater, Luigi Scarso.

LuaTeX merges and builds upon (parts of) the code from these projects:

tex : Donald Knuth
etex : Peter Breitenlohner, Phil Taylor and friends
omega : John Plaice and Yannis Haralambous
aleph : Giuseppe Bilotta
pdftex : Han The Thanh and friends
kpathsea : Karl Berry, Olaf Weber and others
lua : Roberto Ierusalimschy, Waldemar Celes and Luiz Henrique de Figueiredo
metapost : John Hobby, Taco Hoekwater, Luigi Scarso, Hans Hagen and friends
pplib : Paweł Jackowski
fontforge : George Williams (partial)
luajit : Mike Pall (used in LuajitTeX)

Compiled with libpng 1.6.35; using 1.6.35
Compiled with lua version 5.3.5
Compiled with mplib version 2.00
Compiled with zlib 1.2.11; using 1.2.11

Development id: 6930

No experimental, i think.