A pre-fabricated wall system can include a first thin wall module and a second thin wall module. The two thin wall modules have a depth defined by a distance from a front surface of each thin wall module to aback surface of each thin wall module. The pre-fabricated wall system can further include a vertical connection post that has a first connection interface on a first side configured to secure to the first thin wall module. The first connection interface can include a first channel. The vertical connection post can also include a second connection interface on a second side opposite the first side configured to secure to the second thin wall module. The second connection interface can include a second channel. The two thin wall modules can be parallel or co-planar to one another when the two thin wall modules are secured to the vertical connection post.