diff --git a/doc/languages-frameworks/javascript.section.md b/doc/languages-frameworks/javascript.section.md
index 490daf991588..fa10747dacc4 100644
--- a/doc/languages-frameworks/javascript.section.md
+++ b/doc/languages-frameworks/javascript.section.md
@@ -196,7 +196,7 @@ buildNpmPackage rec {
 * `makeCacheWritable`: Whether to make the cache writable prior to installing dependencies. Don't set this unless npm tries to write to the cache directory, as it can slow down the build.
 * `npmBuildScript`: The script to run to build the project. Defaults to `"build"`.
 * `npmFlags`: Flags to pass to all npm commands.
-* `npmInstallFlags`: Flags to pass to `npm ci`.
+* `npmInstallFlags`: Flags to pass to `npm ci` and `npm prune`.
 * `npmBuildFlags`: Flags to pass to `npm run ${npmBuildScript}`.
 * `npmPackFlags`: Flags to pass to `npm pack`.
 
diff --git a/pkgs/build-support/node/build-npm-package/default.nix b/pkgs/build-support/node/build-npm-package/default.nix
index 1038bb2abcb4..5ab86996e56b 100644
--- a/pkgs/build-support/node/build-npm-package/default.nix
+++ b/pkgs/build-support/node/build-npm-package/default.nix
@@ -17,7 +17,7 @@
 , npmBuildScript ? "build"
   # Flags to pass to all npm commands.
 , npmFlags ? [ ]
-  # Flags to pass to `npm ci`.
+  # Flags to pass to `npm ci` and `npm prune`.
 , npmInstallFlags ? [ ]
   # Flags to pass to `npm rebuild`.
 , npmRebuildFlags ? [ ]
diff --git a/pkgs/build-support/node/build-npm-package/hooks/npm-install-hook.sh b/pkgs/build-support/node/build-npm-package/hooks/npm-install-hook.sh
index 4a222de26bbf..c3983e289568 100644
--- a/pkgs/build-support/node/build-npm-package/hooks/npm-install-hook.sh
+++ b/pkgs/build-support/node/build-npm-package/hooks/npm-install-hook.sh
@@ -27,7 +27,7 @@ npmInstallHook() {
     local -r nodeModulesPath="$packageOut/node_modules"
 
     if [ ! -d "$nodeModulesPath" ]; then
-        npm prune --omit dev
+        npm prune --omit dev $npmInstallFlags "${npmInstallFlagsArray[@]}" $npmFlags "${npmFlagsArray[@]}"
         find node_modules -maxdepth 1 -type d -empty -delete
 
         cp -r node_modules "$nodeModulesPath"