Word for "built from ruin"

I'm trying to concisely describe a fictional settlement which was rebuilt from the ruins of a city which once took its place. The only word I can think of which does a decent job at this is "ramshackle," but I'd like to have more than one adjective at my disposal, and ramshackle, in my mind, feels as though it's describing something more quaint than a large settlement. Also, most words I've found on services like thesaurus.com give words similar to "dilapidated," implying that age is the reason for the settlement's poor quality. I don't think this fits my description. Are there any words which do fit this?

Example sentence: "Built from the ruins of the city before it, the [word] settlement is prone to building collapses and lacks the infrastructure which most settlements of its size have."

Here is an adjective given in Lexico

jerry-built
ADJECTIVE

Badly or hastily built with materials of poor quality.
The people living in small, jerry-built houses in the adjacent villages were easy victims of the waves.

This fits the situation you describe:

Built from the ruins of the city before it, the jerry-built settlement is prone to building collapses and lacks the infrastructure which most settlements of its size have.

I don't agree that your adjective dilapidated is apt. It would apply to the state of buildings before they are reconstructed.

As in: TFD adj. haphazard

"Built from the ruins of the city before it, the haphazard settlement is prone to building collapses and lacks the infrastructure which most settlements of its size have."

careless; slipshod

Haphazard is random, disorganized, slipshod, or hit-or-miss... and ramshackle!