Inserting Watermarks into PDF document alternative to pdftk

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It is really annoying that pdftk got removed from Fedora (for what ever reasons) and no proper alternative is provided.

I am looking for software that allows me to insert watermarks into pdf documents.

With pdftk I can just type:

pdftk original.pdf stamp watermark.pdf output final.pdf

In qpdf I could not find an equivalent option!