ghc-debug is a debugging tool for performing precise heap analysis of Haskell programs (check out our previous post introducing it). While working on Eras Profiling, we took the opportunity to make some much needed improvements and quality of life fixes to both the ghc-debug library and the ghc-debug-brick terminal user interface.

To summarise,

• ghc-debug now works seamlessly with profiled executables.
• The ghc-debug-brick UI has been redesigned around a composable, filter based workflow.
• Cost centers and other profiling metadata can now be inspected using both the library interface and the TUI.
• More analysis modes have been integrated into the terminal interface such as the 2-level profile.

This post explores the changes and the new possibilities for inspecting the heap of Haskell processes that they enable. These changes are available by using the 0.6.0.0 version of ghc-debug-stub and ghc-debug-brick.

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