Instructions in ReadMe.md are ambiguous or out-of-date.
The quick start instructions in ReadMe.md are either ambiguous or out of date; i.e., I attempted to follow them, but could not get it to run. It appears to want some code signing, which seems surprising for something that does not attach to other processes.
Or, I misunderstood the instructions. Assume I never used XCode to build something before today, and notice that there are (at least) two things claiming to be MachOExplorer in the left sidebar, as well as a "Product" named MachOExplorer.app (in an alarming red font) at the bottom of that pane. I do not (to my knowledge) have a "development team", nor do I have a "provisioning profile". Those seem to be required.
I have, OTOH, successfully cloned gdb from sources and built it and run it, including code-signing it. Same for Delve.
Switch to the Build Settings tab and click the plus button to add the following User-defined Build Setting:
CODE_SIGNING_ALLOWED = NO
That will force Xcode to skip the code signing step. I will add that to the ReadMe for people who are not enrolled in the Apple Developer program.