The purpose of this study is to provide an overview of the synchronic and diachronic strategies that have led to the preservation of moraicity in noun and verb roots’ syllable structure among Gújjolaay Eegimaa (Bak, Atlantic, Niger-Congo) varieties spoken in southwestern Senegal. Two dialects, or varieties, of Eegimaa are geographically delineated along a peninsula of the Casamance River, locally known as The Kingdom. Cognate noun and verb roots between the two varieties differ phonemically on the basis of geminate consonants versus long vowels. Speakers of the more geographically isolated and conservative variety of Eegimaa use geminate consonants to the exclusion of long vowels, which are witnessed among speakers closer to the river’s borders. An otherwise productive process of lenition fails to apply in both instances: singleton consonants followed by long vowels that correspond with cognates with geminate consonants unexpectedly fail to weaken intervocalically. The under-application of lenition in the variety with long vowels leads to a postulation that geminates were the predecessor to long vowels in the Proto-language, yet no other attested Jóola variety contains contrastive geminates. A comparison between the Eegimaa dialects and more-widely spoken Jóola languages shows that nasal-voiceless plosive clusters are banned only in Eegimaa. Instead, cognates between Eegimaa and other Jóola languages consistently display a geminate or a long vowel in place of an impermissible nasal-consonant cluster. The study appeals to mora preservation through both language contact and historical development as an explanation for the otherwise unusual appearance of geminates in the single Eegimaa variety as well as provides avenues for further research into multilingualism in Casamance, Senegal.