1 - seal the version by removing -SNAPSHOT from version.sbt and push the change
2 - tag the sealed version
git tag x.y.z
git push origin x.y.z
3 - publish the site
sbt docs/clean
sbt docs/makeSite
sbt docs/ghpagesPushSite
4 - sign and publish the artifacts to Sonatype
sbt +publishSigned
5 - release the staging repositories
sbt sonatypeRelease
(or via UI at https://oss.sonatype.org/#stagingRepositories)
6 - start next version development phase by bumping version and putting back -SNAPSHOT in version.sbt