final: prev: {
  # haunt 0.4.0 needs the (commonmark html) module, which the pinned
  # OrangeShark guile-commonmark (unstable-2020-04-30) doesn't provide.
  # Track the Spritely fork that Guix now uses.
  guile-commonmark = prev.guile-commonmark.overrideAttrs (finalAttrs: old: {
    version = "0.1.2-unstable-2024";
    src = final.fetchgit {
      url = "https://codeberg.org/spritely/guile-commonmark";
      rev = "8ebb3041973ee65eed71757c97d09c63b842ac9a";
      hash = "sha256-YYMBUDpRHwscuGv3LieYWHUlOJRJpaK39nLKlpl+ZVE=";
    };
  });

  haunt = prev.haunt.overrideAttrs (finalAttrs: old: {
    version = "0.4.0";
    src = final.fetchgit {
      url = "https://git.dthompson.us/haunt.git";
      tag = "v${finalAttrs.version}";
      hash = "sha256-VRs70ETGB/ygr0HUW5mfGxaLKex0VPbX4r8HCIxV3K0=";
    };
    # 0.4.0 adds a dependency on the (htmlprag) Guile module from guile-lib.
    # guile-gnutls provides the (gnutls) module that (web client) needs for
    # HTTPS, so build-time fetching of remote pages works.
    buildInputs = old.buildInputs ++ [ final.guile-lib final.guile-gnutls ];
  });
}