{
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  "path": "/t/new-haskell-debugger-release-v0-13/13980#post_1",
  "publishedAt": "2026-04-24T16:54:05.000Z",
  "site": "https://discourse.haskell.org",
  "tags": [
    "GHC Debugger",
    "haskell-debugger-0.13",
    "logpoints",
    "github.com:well-typed/haskell-debugger",
    "@fendor",
    "Well-Typed"
  ],
  "textContent": "I’m happy to announce a new release of the new modern step-through interactive debugger (haskell-debugger). You can find installation instructions at GHC Debugger.\n\nHere’s the changelog for haskell-debugger-0.13:\n\nFeatures:\n\n  * Launch the external-interpreter by default directly in the User’s Terminal. That is, the VSCode\nterminal will interpret the debuggee directly, and the stdin/stdout connect will be connected to that terminal.\n  * Add support for `import Module` statements at the debug REPL.\n  * Add logpoints support.\n  * Support for nightly GHC 9.15, leveraging external interpreter commands.\n\n\n\nBug fixes:\n\n  * Fix: Import failed where depended-upon package was incorrectly considered hidden\n  * Fix: Respond cleanly to DAP client with ErrorResponse on exceptions, rather than crashing the session.\n  * Fix: terminate/disconnect/terminated wasn’t following DAP properly, resulting in premature exiting crashes\n  * Fix: Debugger.View.Class cannot be found in certain multi-repl sessions\n  * Fix: Make custom DebugViews instances work for `newtypes`\n  * Fix: Display more unevaluatable closures as `<fn>` rather than as thunks `_`\n  * Fix: Inherit the language extensions at any given breakpoint source to the REPL\n  * Fix: Don’t print certain evaluation results in duplicate\n  * Fix: Set scopeExpensive=true for Module and Global\n\n\n\nAdditionally, the debugger internals and the testsuite were considerably\nrefactored and improved, paving the way for better, faster changes, with more\nconfidence.\n\nThe debugger is supported starting from GHC 9.14, so do try it out on your project if you can.\nBug reports are welcome at github.com:well-typed/haskell-debugger!\n\nThis work is sponsored by Mercury and implemented by me (Rodrigo), Andrea Vezzosi, and @fendor, at Well-Typed",
  "title": "New Haskell Debugger Release: v0.13"
}