Somewhat similarly. It's default mode is authenticated. It handles nonces and IVs for users, unlike NaCl, which demands random nonces from the user. It has and exposes a lot more primitives than libsodium, which is probably a bad thing for security. Its authors (and not just Dan Boneh) have impeccable credentials.

On the other hand, libsodium will outperform SJCL on Node.js, which is really the only safe place to use a library like this.