without setting the build enviroment, the installation fails with
```
1 error found in build log:
35946 fmtutil [INFO]: /usr/local/pkg/Installs/linux-ubuntu18.04-skylake_avx512/gcc7.4.0/texlive/20190410/rgs2nakycorkgzno/t
exmf-var/web2c/pdftex/pdfcslatex.fmt installed.
35947 fmtutil [INFO]: Disabled formats: 6
35948 fmtutil [INFO]: Successfully rebuilt formats: 45
35949 fmtutil [INFO]: Total formats: 51
35950 fmtutil [INFO]: exiting with status 0
35951 ==> [2020-09-07-21:23:21.482745] '/usr/local/pkg/Installs/linux-ubuntu18.04-skylake_avx512/gcc7.4.0/texlive/20190410/
rgs2nakycorkgzno/bin/x86_64-linux/mtxrun' '--generate'
>> 35952 /usr/bin/env: 'texlua': No such file or directory
```
May be there is a better way...
e2e90e4d6b