In some examples, a technique may include positioning a first part comprising a ceramic or ceramic matrix composite and a second part comprising a ceramic or a CMC adjacent to each other to define a joint region at the interface of the first part and the second part. In some examples, the joint region may be heated using at least one of a laser or a plasma arc source to heat the joint region to an elevated temperature. The first and second parts may be pressed together and cooled to join the first and second parts at the joint region. In other examples, a solid braze material including a filler material and a metal or alloy may be delivered to the joint region and locally heated to cause a constituent of the filler material and a constituent of the metal or alloy to react. When reacted, the constituents may form a solid material, which may join the first and second parts.