hls-graph - a limited reimplementation of Shake for in-memory build graphs

ghcide was originally built on top of Shake, a Haskell build system. Nowadays Shake has been replaced by a special purpose implementation of a build graph called hls-graph, which drops all the persistency features in exchange for simplicity and performance.

Features:

• Dynamic dependencies
• User defined rules (there are no predefined File rules as in Shake)
• Build reports (a la Shake profiling)
• "Reactive" change tracking for minimal rebuilds (not available in Shake)

What's missing:

• Persistence
• A default set of rules for file system builds
• A testsuite
• General purpose application - many design decisions make assumptions specific to ghcide