BSD-3-Clause licensed and maintained by Brandon Chinn
This version can be pinned in stack with:hpc-lcov-1.1.0@sha256:5663526c1a74c843b611a77b2a03cf6fe5bf2b7984b33ce6a1a7ba968fb54b87,2763

Module documentation for 1.1.0


GitHub Actions codecov Hackage

Convert HPC output into files that can be uploaded to coverage services, like Codecov.



  1. Run stack install hpc-lcov
  2. Run your test(s) with coverage, e.g. stack test --coverage
  3. Run hpc-lcov
  4. Upload the generated file to your coverage service


Coming soon! (


How do I convert coverage for an executable?

Note: If you have both tests and executables, HPC will write module information to the same file. Because of this, you’ll have to load the coverage for each separately, with a stack clean in between.

  1. Build a single executable with coverage enabled (e.g. stack build :my-exe --coverage)
  2. Run the executable
  3. This should generate a .tix file in the current directory
  4. Run the following, specifying the package that builds the executable:
    stack exec -- hpc-lcov --file my-exe.tix --main-package my-package

How do I merge coverage files?

  1. Install LCOV (e.g. brew install lcov)

  2. Run

    lcov -a -a ... >




  • Drop support for GHC < 8.6


Bug fix:

  • Don’t error if the packages field in stack.yaml doesn’t exist


Initial release of hpc-lcov:

  • Generates LCOV files from HPC .tix files
  • Discovers .tix files generated by Stack test suites
  • Allows manually specifying a .tix file (useful for executables with coverage enabled)