This looks pretty interesting. Most striking to me is that Go is taking from other 'target' languages. You can see the 5x5 block of the other strongest target languages giving to Go, but not taking from it. To make what the Eigenvector says explicit:

Top 5 giving to Go directly: C, Python, Java, Ruby, Scala

Top 5 giving to C: C#, R, Java', C++, Fortran

Top 5 giving to Python: C', Perl, Java', C#, C++

Top 5 giving to Java: C', C++, PHP, Python', C#

Top 5 giving to Ruby: Python', PHP, Perl, Java', (C++ — only 215)

Top 5 giving to Scala: Java', Ruby, (Python', C#, PHP — only 100, 17, 16)

': language also in top 5 givers to Go.

The other top languages take from each other (there is migration in both directions), but currently Go mostly takes here. However it does lose people to Rust — which is actually the strongest go-to language from Go. And C++ does not give to go.

This might point to a discrepancy between Go marketing and reality (efficiency and replacing C++).

It would be great if you could repeat this exercise next year to see how things changed.

(besides: the script is nice and concise!)