Caching NDK when debugging an app build

Hello,
I’m trying to build my App using “Submitting to F-Droid Quick Start Guide” and I noticed that I need to re run the container and start the build process many times as I’m trying to get it to work. I noticed that each time the build process start downloading Android NDK

2022-06-07 03:59:11,242 WARNING: Android NDK version 'r23c' could not be found!
2022-06-07 03:59:11,242 WARNING: Configured versions:
2022-06-07 03:59:11,243 INFO: Downloading https://dl.google.com/android/repository/android-ndk-r23c-linux.zip

I wonder if there is an easy way to save it somewhere and not having to redownload it each time I’m debugging my app.

Thank you.

Isn’t there a cache option in config.yml?

Where exactly I should copy config.yml file to?

I understand I should comment the line with cachedir: cache:

# Directory to store downloaded tools in (i.e. gradle versions)
# By default, these are stored in ~/.cache/fdroidserver
cachedir: cache

Should I put config.yml in fdroiddata folder as in the Build Server Setup?

fdroid:~$ cp fdroidserver/examples/config.yml fdroiddata/

yes.

and always start your builds commands from the fdroiddata/ folder

Just tested it in a freshly created VPS, cache doesn’t seem to work for me:

sammy@test6:~$ grep "cache" /home/sammy/fdroiddata/config.yml 
# By default, these are stored in ~/.cache/fdroidserver
cachedir: cache
sammy@test6:~$