My signature is not validated by other implementations. What is wrong?
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Try to reverse it (like sign[::-1] in Python).
Try to swap its halves (sign[len(sign)//2:] + sign[:len(sign)//2]).
Try to reverse its swapped halves too.

          It is GOST: do you expect serialization unification?

    My signature is *still* not validated by other implementations!
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Try to reverse digest you are signing/verifying (dgst[::-1]).

          It is GOST: do you expect serialization unification?

          Everything above did not help me. Does GoGOST sucks?
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No way! You still have not tried to reverse your binary private key,
public key and swap its halves.

          It is GOST: do you expect serialization unification?