Unfortunately, we lost our release signing private key, and we didn't have a revocation certificate :(
We have a new one out now available on MIT's PGP key server. Its fingerprint is 59E790FEC63109BF22BD35ABEA9D8C8A6F75CB28.
We'll also provide SHA256 hashes for our releases as well in case you want a simpler way to verify releases.
My apologies for losing this key,