This is a required update as there is/was a hard fork at block 109,000. If you are updating after the fork, you may need to delete your consensus.db file and resync
Command Line Version 1.5.1
Source
Download from source and compile
All binaries are signed. Manually verify the signature with the command:
openssl dgst -sha256 -verify siaprime_dev_public.pem -signature spd.sig spd
download the key
Bootstrap
If you prefer not to wait for the blockchain to sync, download a bootstrap of the latest consensus