Database of malware analysis reports (fictional): from a file's hash (SHA-256 or MD5), see what analysts know about it without ever running it: detections, behaviour, related files, strings and build metadata. You can also search for a malware family name.

In real life: VirusTotal, MalwareBazaar, Hybrid Analysis, ANY.RUN. Build metadata sometimes give developers away: the path of the debug file (PDB) often contains the Windows username or the project name.