diff --git a/scripts/check-comment-blocks.sh b/scripts/check-comment-blocks.sh
index c3b90fe6..94da77cf 100755
--- a/scripts/check-comment-blocks.sh
+++ b/scripts/check-comment-blocks.sh
@@ -11,8 +11,8 @@
 #
 # Scope: tracked *.rs *.nix *.sh *.js *.ts *.css *.html. Markdown is exempt
 # (it is prose by nature). Comment forms: `#` line comments (nix/sh), `//`
-# line comments (rs/js/ts), and `/* */` (rs/js/ts/css) + `<!-- -->` (html)
-# block comments. A blank line separates two line-comment blocks (does NOT
+# line comments (rs/js/ts), and `/* */` block comments (nix/rs/js/ts/css) +
+# `<!-- -->` (html). A blank line separates two line-comment blocks (does NOT
 # extend a run); a blank inside a `/* */` / `<!-- -->` block stays part of it.
 #
 # Escape hatch: a `lint:allow-long-comment` marker anywhere in a block
@@ -27,7 +27,8 @@ hits="$(
   git ls-files -z '*.rs' '*.nix' '*.sh' '*.js' '*.ts' '*.css' '*.html' \
     | xargs -0 -r awk -v MAX="$MAX" '
         function mode_of(fn) {
-          if (fn ~ /\.(nix|sh)$/)   return "hash"
+          if (fn ~ /\.nix$/)        return "nix"
+          if (fn ~ /\.sh$/)         return "hash"
           if (fn ~ /\.(rs|js|ts)$/) return "slash"
           if (fn ~ /\.css$/)        return "cstyle"
           if (fn ~ /\.html$/)       return "html"
@@ -47,6 +48,10 @@ hits="$(
             if (index($0, blockend) > 0) inblock = 0
           } else if (mode == "hash") {
             if ($0 ~ /^[ \t]*#/) c = 1
+          } else if (mode == "nix") {
+            # nix: `#` line comments AND `/* */` block comments.
+            if ($0 ~ /^[ \t]*#/) c = 1
+            else if ($0 ~ /^[ \t]*\/\*/) { c = 1; if (index($0, "*/") == 0) { inblock = 1; blockend = "*/" } }
           } else if (mode == "slash") {
             if ($0 ~ /^[ \t]*\/\//) c = 1
             else if ($0 ~ /^[ \t]*\/\*/) { c = 1; if (index($0, "*/") == 0) { inblock = 1; blockend = "*/" } }