Hi, @BlackLemon. About this:
Functions deployed at Netlify are running in AWS Lambda. Lambda itself has this limitation:
Quoting that page above:
| Function environment variables | 4 KB, for all environment variables associated with the function, in aggregate |
The most common workaround for this is to make the environment variable only available to the build system and not the to deployed functions. Then, during the build process, the build writes the environment variables into the source files themselves. This keeps the data out of the Git repo but still places the data as text in the source files.
If there are other questions about this, please let us know.