anchor.diff:      service-identity pyyaml
     ];
   
  +  # Install the documentation.
     postInstall = ''
  -    # Install the documentation.
  -    mkdir -p "$out/share/doc/${name}"
  -    cp -rv "docs/"* "$out/share/doc/${name}"
  -    find "$out/share/doc/${name}" -name Makefile -exec rm -v {} \;
  +    (
  +      cd docs
  +
  +      make singlehtml
  +      mkdir -p "$doc/share/doc/${name}"
  +      cp -rv _build/singlehtml/* "$doc/share/doc/${name}"
  +
  +      make info
  +      mkdir -p "$info/share/info"
  +      cp -rv _build/texinfo/*.info "$info/share/info"
  +    )
     '';
   
     checkPhase = ''
  
positive.code: { fetchurl, lib, unzip, nettools, pythonPackages }:
  
  # FAILURES: The "running build_ext" phase fails to compile Twisted
  # plugins, because it tries to write them into Twisted's (immutable)
  
negative.code:     sed -i 's/"pycrypto.*"/"pycrypto"/' src/allmydata/_auto_deps.py
    '';
  
    nativeBuildInputs = with pythonPackages; [ sphinx texinfo ];
  
    buildInputs = with pythonPackages; [ unzip numpy mock ];
  
    # The `backup' command requires `sqlite3'.
  