anchor.diff:  
     vim-prosession = buildVimPluginFrom2Nix {
       pname = "vim-prosession";
  -    version = "2020-10-12";
  +    version = "2020-11-01";
       src = fetchFromGitHub {
         owner = "dhruvasagar";
         repo = "vim-prosession";
  -      rev = "e735468710a5cd6037b6d4c0e4c8c2bc1353cf4b";
  -      sha256 = "0ava297hpm1cf8j18ypfrziwavqcv982hisvh1d8yjxal521pam1";
  +      rev = "1be0c069a2b362369913ffaeed5293ffe1932ef6";
  +      sha256 = "0hqfwlkz64kkh8w6w5k7gw2i0x7spddbgixjcrp1lr6n6bslkj2d";
       };
       meta.homepage = "https://github.com/dhruvasagar/vim-prosession/";
     };
  
positive.code: 
    nvim-treesitter = buildVimPluginFrom2Nix {
      pname = "nvim-treesitter";
      version = "2020-10-30";
      src = fetchFromGitHub {
        owner = "nvim-treesitter";
        repo = "nvim-treesitter";
        rev = "dd7900fc44b9cc6773bd4f8b5c0175887991520c";
        sha256 = "0nfdvmlzqfga596n5awdhz9mc6gwnys73ixxkqi49f2g9x215ksd";
      };
      meta.homepage = "https://github.com/nvim-treesitter/nvim-treesitter/";
    };
  
negative.code: 
    lean-vim = buildVimPluginFrom2Nix {
      pname = "lean-vim";
      version = "2020-11-01";
      src = fetchFromGitHub {
        owner = "leanprover";
        repo = "lean.vim";
        rev = "d1b3037680be79f114a87620844117e20ca7efcf";
        sha256 = "0x3cz4is30jsrp7dym4rz4xngv9mimybl4kqnry9x0nkqzn55910";
      };
      meta.homepage = "https://github.com/leanprover/lean.vim/";
    };
  