Original proposal: https://github.com/nginx/njs/pull/988
Enhanced version merged upstream in: https://github.com/nginx/njs/pull/989
diff --git a/src/quickjs_compat.h b/src/quickjs_compat.h
index 3b7a618c7..7753086d3 100644
--- a/src/quickjs_compat.h
+++ b/src/quickjs_compat.h
@@ -22,3 +22,7 @@
 #ifndef JS_BOOL
     #define JS_BOOL bool
 #endif
+
+#ifdef QUICKJS_NG
+    #define JS_IsError(cx, val) JS_IsError(val)
+#endif

diff --git a/auto/quickjs b/auto/quickjs
index 8d6b544f9..c574c83f3 100644
--- a/auto/quickjs
+++ b/auto/quickjs
@@ -7,6 +7,10 @@ NJS_QUICKJS_LIB=
 NJS_HAVE_QUICKJS=NO
 NJS_QUICKJS_DEFAULT_INCS="src $NJS_BUILD_DIR"
 
+# Alternative pkg-config binary can be supplied by setting the PKG_CONFIG
+# environment variable.
+: "${PKG_CONFIG:=pkg-config}"
+
 if [ $NJS_TRY_QUICKJS = YES ]; then
     njs_found=no
 
@@ -57,6 +61,20 @@ if [ $NJS_TRY_QUICKJS = YES ]; then
         . auto/feature
     fi
 
+    if [ $njs_found = no ]; then
+        njs_feature="QuickJS-NG library via pkg-config"
+
+        flags="$("${PKG_CONFIG}" --cflags-only-I quickjs-ng)"
+        # Trim the -I prefix from includes.
+        pkg_config_includes="$(printf "%s\n" "$flags" | sed 's|-I||g')"
+        pkg_config_libs="$("${PKG_CONFIG}" --libs quickjs-ng)"
+
+        njs_feature_incs="$NJS_QUICKJS_DEFAULT_INCS ${pkg_config_includes}"
+        njs_feature_libs="-lm -ldl -lpthread ${pkg_config_libs}"
+
+        . auto/feature
+    fi
+
 
     if [ $njs_found = yes ]; then
 
diff --git a/nginx/config b/nginx/config
index 3386dac08..0a74cd969 100644
--- a/nginx/config
+++ b/nginx/config
@@ -26,6 +26,10 @@ NJS_QUICKJS_INC=
 NJS_QUICKJS_DEFAULT_INCS="$ngx_addon_dir/../src $ngx_addon_dir/../build"
 NJS_HAVE_QUICKJS=
 
+# Alternative pkg-config binary can be supplied by setting the PKG_CONFIG
+# environment variable.
+: "${PKG_CONFIG:=pkg-config}"
+
 if [ $NJS_QUICKJS != NO ]; then
 
     ngx_feature="QuickJS library -lquickjs.lto"
@@ -71,6 +75,21 @@ if [ $NJS_QUICKJS != NO ]; then
         . auto/feature
     fi
 
+    if [ $ngx_found = no ]; then
+        ngx_feature="QuickJS-NG library via pkg-config"
+
+        flags="$("${PKG_CONFIG}" --cflags-only-I quickjs-ng)"
+        # Trim the -I prefix from includes.
+        pkg_config_includes="$(printf "%s\n" "$flags" | sed 's|-I||g')"
+        pkg_config_libs="$("${PKG_CONFIG}" --libs quickjs-ng)"
+
+        ngx_feature_path="$NJS_QUICKJS_DEFAULT_INCS ${pkg_config_includes}"
+        ngx_feature_libs="-lm -ldl -lpthread ${pkg_config_libs}"
+
+        . auto/feature
+    fi
+
+
     if [ $ngx_found = yes ]; then
 
         ngx_feature="QuickJS JS_GetClassID()"