diff --git a/lib/http.js b/lib/http.js
index ce7bdff..a810d39 100644
--- a/lib/http.js
+++ b/lib/http.js
@@ -18,9 +18,14 @@ import net from 'net';
 import url from 'url';
 import Cookie from 'cookiejar';
 import charset from 'charset';
-import qs from 'qs';
+import * as pq from 'picoquery';
 import * as _request from './request.js';
 
+const PQ_OPTIONS = {
+  nesting: true,
+  nestingSyntax: 'index'
+};
+
 /**
  *
  * @param {ChaiStatic} chai
@@ -384,7 +389,7 @@ export default function (chai, _) {
   Assertion.addMethod('param', function () {
     const assertion = new Assertion();
     _.transferFlags(this, assertion);
-    assertion._obj = qs.parse(url.parse(this._obj.url).query);
+    assertion._obj = pq.parse(url.parse(this._obj.url).query, PQ_OPTIONS);
     assertion.property.apply(assertion, arguments);
   });
 
diff --git a/package-lock.json b/package-lock.json
index 72375ea..4647f2e 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -14,7 +14,7 @@
         "cookiejar": "^2.1.4",
         "is-ip": "^5.0.1",
         "methods": "^1.1.2",
-        "qs": "^6.12.1",
+        "picoquery": "^1.4.0",
         "superagent": "^9"
       },
       "devDependencies": {
@@ -1824,6 +1824,11 @@
         "node >=0.6.0"
       ]
     },
+    "node_modules/fast-decode-uri-component": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/fast-decode-uri-component/-/fast-decode-uri-component-1.0.1.tgz",
+      "integrity": "sha512-WKgKWg5eUxvRZGwW8FvfbaH7AXSh2cL+3j5fMGzUMCxWBJ3dV3a7Wz8y2f/uQ0e3B6WmodD3oS54jTQ9HVTIIg=="
+    },
     "node_modules/fast-deep-equal": {
       "version": "3.1.3",
       "resolved": "https://registry.npmjs.org/fast-deep-equal/-/fast-deep-equal-3.1.3.tgz",
@@ -3625,6 +3630,14 @@
         "url": "https://github.com/sponsors/jonschlinkert"
       }
     },
+    "node_modules/picoquery": {
+      "version": "1.4.0",
+      "resolved": "https://registry.npmjs.org/picoquery/-/picoquery-1.4.0.tgz",
+      "integrity": "sha512-VIq9N+nQgmiN6DsAgs7EcAjUezgppBR4zahSu/Q0H0pylLu9e9BORK91n/kmW7wfkHRnNnIn9IIB8uaI7ElvTg==",
+      "dependencies": {
+        "fast-decode-uri-component": "^1.0.1"
+      }
+    },
     "node_modules/pidtree": {
       "version": "0.6.0",
       "resolved": "https://registry.npmjs.org/pidtree/-/pidtree-0.6.0.tgz",
diff --git a/package.json b/package.json
index 5d9550b..e3a7808 100644
--- a/package.json
+++ b/package.json
@@ -48,15 +48,14 @@
   "browser": {
     "http": false,
     "https": false,
-    "net": "./lib/net.js",
-    "querystring": "qs"
+    "net": "./lib/net.js"
   },
   "dependencies": {
     "charset": "^1.0.1",
     "cookiejar": "^2.1.4",
     "is-ip": "^5.0.1",
     "methods": "^1.1.2",
-    "qs": "^6.12.1",
+    "picoquery": "^1.4.0",
     "@types/superagent": "^8.1.7",
     "superagent": "^9"
   },