"zope.interface",
- "Twisted >= 2.4.0",
+ # On Windows we need at least Twisted 9.0 to avoid an indirect dependency on pywin32.
+ # We also need Twisted 10.1 for the FTP frontend in order for Twisted's FTP server to
+ # support asynchronous close.
+ "Twisted >= 10.1.0",
# foolscap < 0.5.1 had a performance bug which spent
# O(N**2) CPU for transferring large mutable files