This page shows how different Go libraries generate a unique id:

github.com/rs/xid	dbrc88pmgkj2ae05lq1g
github.com/segmentio/ksuid	3M2mJM5tjTp4vlMdedEUO5c1V0D
github.com/oklog/ulid	01M79YWANAYH0ACDTQS7ED89VM
github.com/sony/sonyflake	8f6f121dd000001
github.com/chilts/sid	1794556963499204358-8614987492883061745
github.com/satori/go.uuid	7699bac7-2bbf-4b39-a1ad-12a34551fffb

Learn more about those libraries.