diff --git a/src/lib/utils.js b/src/lib/utils.js
index dd2c760a..d468eb73 100644
--- a/src/lib/utils.js
+++ b/src/lib/utils.js
@@ -142,7 +142,7 @@ let match = (path, uri) => pick([{ path }], uri);
 // require less contextual information and (fingers crossed) be more intuitive.
 let resolve = (to, base) => {
   // /foo/bar, /baz/qux => /foo/bar
-  if (startsWith(to, "/")) {
+  if (typeof to === "number" || startsWith(to, "/")) {
     return to;
   }
 
diff --git a/src/lib/utils.test.js b/src/lib/utils.test.js
index b34deb29..08051119 100644
--- a/src/lib/utils.test.js
+++ b/src/lib/utils.test.js
@@ -84,6 +84,7 @@ describe("resolve", () => {
     expect(resolve("/groups?some=query", "/users?some=thing")).toEqual(
       "/groups?some=query"
     );
+    expect(resolve(-1)).toEqual(-1);
   });
 });