Important edit :
If the code is an add-on or adjustment to other (prior) open-source software ... probably doesn't matter. What does matter, is what exactly the code does. If it isn't related to "cryptanalysis" then there shouldn't be an issue.
According to German export control: Under item 5D002a3a, code that is developed or modified to use "cryptoanalysis" software is also subject to control.
That seems to make it irrelevant what exactly the new code does - it depends on what the repo (or any other part of the repo) is considered.
If the code is an add-on or adjustment to other (prior) open-source software ... probably doesn't matter. What does matter, is what exactly the code does. If it isn't related to "cryptanalysis" then there shouldn't be an issue.
According to German export control: Under item 5D002a3a, code that is developed or modified to use "cryptoanalysis" software is also subject to control.
That seems to make it irrelevant what exactly the new code does - it depends on what the repo (or any other part of the repo) is considered.