Disclosed herein are microelectronic assemblies including microelectronic components coupled by direct bonding, and related structures and techniques. In some embodiments, a microelectronic assembly may include a first microelectronic component including a first guard ring extending through at least a portion of a thickness of and along a perimeter; a second microelectronic component including a second guard ring extending through at least a portion of a thickness of and along a perimeter, where the first and second microelectronic components are coupled by direct bonding; and a seal ring formed by coupling the first guard ring to the second guard ring. In some embodiments, a microelectronic assembly may include a microelectronic component coupled to an interposer that includes a first liner material at a first surface; a second liner material at an opposing second surface; and a perimeter wall through the interposer and connected to the first and second liner materials.