A library has been released for BLS signature aggregation using a construction based on Musig. Musig is a scheme for non-interactive signature aggregation built on the Bellare-Nevan multisignature scheme which makes it possible to create just one public key from multiple public keys.
BLS signatures can be aggregated non-interactively although it makes the process slightly slower. They also have the same aggregation features with Schnorr signatures such as a resulting signature of constant size, reduced data size for easy validation and transmission on networks and high security.
This release is the first draft but is fully functional however it’s not yet reviewed for security.
An other known BLS library can also be found here