diff --git a/src/ReactDOMTestUtils.re b/src/ReactDOMTestUtils.re
index 82c5d606d..a51814378 100644
--- a/src/ReactDOMTestUtils.re
+++ b/src/ReactDOMTestUtils.re
@@ -123,7 +123,9 @@ module DOM = {
 
   let findBySelectorAndPartialTextContent = (element, selector, content) =>
     querySelectorAll(element, selector)
-    |> Array.find_opt(node => node->textContent->Js.String2.includes(content));
+    |> Array.find_opt(node =>
+         Js.String.includes(~sub=content, node->textContent, ())
+       );
 };
 
 let prepareContainer = (container: ref(option(Dom.element)), ()) => {
diff --git a/src/ReasonReactRouter.re b/src/ReasonReactRouter.re
index 89603b17a..e6574e54d 100644
--- a/src/ReasonReactRouter.re
+++ b/src/ReasonReactRouter.re
@@ -73,23 +73,22 @@ let pathParse = str =>
   | "/" => []
   | raw =>
     /* remove the preceeding /, which every pathname seems to have */
-    let raw = Js.String.sliceToEnd(~from=1, raw);
+    let raw = Js.String.slice(~start=1, raw, ());
     /* remove the trailing /, which some pathnames might have. Ugh */
     let raw =
       switch (Js.String.get(raw, Js.String.length(raw) - 1)) {
-      | "/" => Js.String.slice(~from=0, ~to_=-1, raw)
+      | "/" => Js.String.slice(~start=0, ~end_=-1, raw, ())
       | _ => raw
       };
     /* remove search portion if present in string */
     let raw =
-      switch (raw |> Js.String.splitAtMost("?", ~limit=2)) {
+      switch (Js.String.split(~sep="?", ~limit=2, raw, ())) {
       | [|path, _|] => path
       | _ => raw
       };
 
-    raw
-    |> Js.String.split("/")
-    |> Js.Array.filter(item => String.length(item) != 0)
+    Js.String.split(~sep="/", raw, ())
+    |> Js.Array.filter(~f=item => String.length(item) != 0)
     |> arrayToList;
   };
 let path = (~serverUrlString=?, ()) =>
@@ -109,7 +108,7 @@ let hash = () =>
     | raw =>
       /* remove the preceeding #, which every hash seems to have.
          Why is this even included in location.hash?? */
-      raw |> Js.String.sliceToEnd(~from=1)
+      Js.String.slice(~start=1, raw, ())
     }
   };
 let searchParse = str =>
@@ -117,7 +116,7 @@ let searchParse = str =>
   | ""
   | "?" => ""
   | raw =>
-    switch (raw |> Js.String.splitAtMost("?", ~limit=2)) {
+    switch (Js.String.split(~sep="?", ~limit=2, raw, ())) {
     | [|_, search|] => search
     | _ => ""
     }
diff --git a/test/React__test.re b/test/React__test.re
index 8b26c8339..eba55d20f 100644
--- a/test/React__test.re
+++ b/test/React__test.re
@@ -335,7 +335,7 @@ describe("React", () => {
             fallback={({error: _, info}) => {
               expect(
                 info.componentStack
-                ->Js.String2.includes("ComponentThatThrows"),
+                ->Js.String.includes(~sub="ComponentThatThrows", ()),
               )
               ->toBe(true);
               <strong> "An error occured"->React.string </strong>;