Singularity is a Cassette in Deathloop.
Location
Found in Wenjie's quarters in the Blue Laboratory Annex in the Complex (her quarters are locked, the code is found in the Aesthetics are Key note). It is on a desk in the corner of the room.
Transcript
Wenjie A: It's at night. Our breach will be closed. Which means...
Wenjie B: There will only be one of us. It's -
Wenjie A: Dangerous. According to our calculations, all the visiting Wenjies will just slip back into their timelines and only leave one.
Wenjie B: Under no circumstances are we to leave this facility. Evans' Second Law of...
Wenjie A: Variation, yes, I wrote it.
Wenjie B: We.
Wenjie A: Wenjie, if the technology behind that door helps create a stable breach... SHE will have to go.
Colt Note
Wenjie wants through a door almost as badly as she wants to avoid Aleksis.