finally :)

flake.lock

@@ -34,16 +34,16 @@
     "rainbow-vim-src": {
       "flake": false,
       "locked": {
-        "lastModified": 1446104795,
-        "narHash": "sha256-aM3sMbRaAU/hUjRBiUiy9CleJW+ZoFb3CEDFhQ2W60c=",
-        "owner": "junegunn",
-        "repo": "rainbow_parentheses.vim",
-        "rev": "27e7cd73fec9d1162169180399ff8ea9fa28b003",
+        "lastModified": 1590654574,
+        "narHash": "sha256-PH4UY+/1JFrR5C0DpFrkfTc51wUQet8ynvAPKFxbFZk=",
+        "owner": "luochen1990",
+        "repo": "rainbow",
+        "rev": "4d15633cdaf61602e1d9fd216a77fc02e0881b2d",
         "type": "github"
       },
       "original": {
-        "owner": "junegunn",
-        "repo": "rainbow_parentheses.vim",
+        "owner": "luochen1990",
+        "repo": "rainbow",
         "type": "github"
       }
     },

flake.nix

@@ -10,7 +10,7 @@
     };
 
     rainbow-vim-src = {
-      url = "github:junegunn/rainbow_parentheses.vim";
+      url = "github:luochen1990/rainbow";
       flake = false;
     };
     vim-racket-src = {

overlay.nix

@@ -19,6 +19,8 @@ customPlugins: self: super: {
           filetype plugin on
           filetype indent on
 
+          syntax on
+          colorscheme delek
 
           if has("autocmd")
             au BufReadPost *.rkt,*.rktl set filetype=racket
@@ -43,11 +45,15 @@ customPlugins: self: super: {
           set tabstop=2 softtabstop=2 expandtab shiftwidth=2 smarttab
 
           let g:rainbow_active = 1
-          let g:rainbow_ctermfgs = [ 'lightblue', 'lightgreen', 'yellow', 'red', 'magenta']
       
           imap <C-L> λ
-          syntax on
-          colorscheme default
+
+          let g:rainbow_conf = {
+           \ 'ctermfgs': ['red', 'green', 'blue', 'cyan', 'magenta'],
+           \ 'cterms': ['bold']
+           \}
+
+
         '';
       };
     };