The drum sounds should all be fairly obvious. But what might not be so immediately obvious is that one of the drum sounds became the warbly synth sound in the melody. I did this by playing the sound through a synthesizer and gradually shortening the sample length until it became a tone (at about 20 - 22 seconds in...)
I took a sample of this tone and used it in the synthesizer to play the melody.
I added a glitch effect and some reverb to the melody. The last little bit of beeping is from the feedback created by the glitch effect.
Here is a complete list of the sounds I used: