Coda clusters are not terribly common, and the majority are found in words of Dutch or English etymology, djaweps (Thursday) being one of the few exceptions. This suggests that (most) coda clusters represent a post-formative development, as a result of vocabulary expansion through borrowing from Dutch, and later also English.
Coda clusters may consist of liquid or nasal + obstruent or of obstruent + obstruent; note though that not all combinations are possible.
Source: Joubert 2002
Source: Joubert 2002
Source: Joubert 2002