diff --git a/src/fetch.ts b/src/fetch.ts
index 3c2b440..bae99e7 100644
--- a/src/fetch.ts
+++ b/src/fetch.ts
@@ -1,6 +1,6 @@
 import type { Readable } from "node:stream";
 import destr from "destr";
-import { withBase, withQuery } from "ufo";
+import { withBase, withQuery } from "./path";
 import { createFetchError } from "./error";
 import {
   isPayloadMethod,
diff --git a/src/path.ts b/src/path.ts
new file mode 100644
index 0000000..b49cf2a
--- /dev/null
+++ b/src/path.ts
@@ -0,0 +1,133 @@
+/* eslint-disable unicorn/prefer-at */
+export type QueryValue =
+  | string
+  | number
+  | boolean
+  | QueryValue[]
+  | Record<string, any>
+  | null
+  | undefined;
+export type QueryObject = Record<string, QueryValue | QueryValue[]>;
+
+/**
+ * Removes the leading slash from the given path if it has one.
+ */
+export function withoutLeadingSlash(path?: string): string {
+  if (!path || path === "/") {
+    return "/";
+  }
+
+  return path[0] === "/" ? path.slice(1) : path;
+}
+
+/**
+ * Removes the trailing slash from the given path if it has one.
+ */
+export function withoutTrailingSlash(path?: string): string {
+  if (!path || path === "/") {
+    return "/";
+  }
+
+  return path[path.length - 1] === "/" ? path.slice(0, -1) : path;
+}
+
+/**
+ * Joins the given base URL and path, ensuring that there is only one slash between them.
+ */
+export function joinURL(base?: string, path?: string): string {
+  if (!base || base === "/") {
+    return path || "/";
+  }
+
+  if (!path || path === "/") {
+    return base || "/";
+  }
+
+  const baseHasTrailing = base[base.length - 1] === "/";
+  const pathHasLeading = path[0] === "/";
+  if (baseHasTrailing && pathHasLeading) {
+    return base + path.slice(1);
+  }
+
+  if (!baseHasTrailing && !pathHasLeading) {
+    return `${base}/${path}`;
+  }
+
+  return base + path;
+}
+
+/**
+ * Adds the base path to the input path, if it is not already present.
+ */
+export function withBase(input = "", base = ""): string {
+  if (!base || base === "/") {
+    return input;
+  }
+
+  const _base = withoutTrailingSlash(base);
+  if (input.startsWith(_base)) {
+    return input;
+  }
+
+  return joinURL(_base, input);
+}
+
+/**
+ * Returns the URL with the given query parameters. If a query parameter is undefined, it is omitted.
+ */
+export function withQuery(input: string, query?: QueryObject): string {
+  if (!query || Object.keys(query).length === 0) {
+    return input;
+  }
+
+  const searchIndex = input.indexOf("?");
+
+  if (searchIndex === -1) {
+    const normalizedQuery = Object.entries(query)
+      .filter(([, value]) => value !== undefined)
+      .flatMap(([key, value]) => {
+        if (Array.isArray(value)) {
+          return value.map((item) => [key, normalizeQueryValue(item)]);
+        }
+
+        return [[key, normalizeQueryValue(value)]];
+      });
+    const searchParams = new URLSearchParams(normalizedQuery);
+    const queryString = searchParams.toString();
+    return queryString ? `${input}?${queryString}` : input;
+  }
+
+  const searchParams = new URLSearchParams(input.slice(searchIndex + 1));
+  const base = input.slice(0, searchIndex);
+
+  for (const [key, value] of Object.entries(query)) {
+    if (value === undefined) {
+      searchParams.delete(key);
+    } else if (Array.isArray(value)) {
+      for (const item of value) {
+        searchParams.append(key, normalizeQueryValue(item));
+      }
+    } else {
+      searchParams.set(key, normalizeQueryValue(value));
+    }
+  }
+
+  const queryString = searchParams.toString();
+  return queryString ? `${base}?${queryString}` : base;
+}
+
+function normalizeQueryValue(value: QueryValue): string {
+  if (value === null) {
+    return "";
+  }
+
+  if (typeof value === "number" || typeof value === "boolean") {
+    return String(value);
+  }
+
+  if (typeof value === "object") {
+    return JSON.stringify(value);
+  }
+
+  return String(value);
+}