Ambrose, this comment is directed to you, with no intended bearing on this ticket ASYNC-86.
Just an FYI regarding core.typed that I have found it not exactly fun, but it has eliminated some problems by having Eastwood copy the source code of tools.analyzer(.jvm) and its dependencies, with renamed namespaces, into its own source tree. This enables Eastwood to analyze+eval source code of any version of those libraries without causing conflicts. I have a pre-alpha version of a tool to assist in automating parts of this copy&rename called Dolly . If Dolly was polished some more, it might become useful to you for this purpose in core.typed.
Benedek Fazekas has created a tools called MrAnderson  for the same purpose (independently developed from Dolly). I haven't looked into the details of how it works yet, but it may do a better job than Dolly 0.1.0.
 https://github.com/jafingerhut/dolly for the library, https://github.com/jonase/eastwood/blob/master/copy-deps-scripts/README.md#using-dolly-to-copy-dependencies-into-eastwood-source-code for copy-and-paste-into-a-REPL forms that I use to copy in updated versions of Eastwood dependencies into its source tree. The polishing I mention above would cut that down significantly.
 https://github.com/benedekfazekas/mranderson I learned about this lib from a Github issue on Eastwood, where there is a little bit of discussion: https://github.com/jonase/eastwood/issues/87