diff --git a/README.md b/README.md
index 9596e1f..8208a9d 100644
--- a/README.md
+++ b/README.md
@@ -22,7 +22,7 @@ it works.
 You need a recent version of Rust, which is most easily installed with
 [rustup.rs](https://rustup.rs).
 
-In addition, you will also need [Trunk](https://trunkrs.dev/), which is a tool
+In addition, you will also need [Trunk](https://trunk-rs.github.io/trunk/), which is a tool
 that helps to build Rust WebAssembly applications, and the WebAssembly build
 target for Rust.  You can install it like this:
 
diff --git a/src/components/file_tree.rs b/src/components/file_tree.rs
index 0fbf1f0..a550262 100644
--- a/src/components/file_tree.rs
+++ b/src/components/file_tree.rs
@@ -22,8 +22,8 @@ impl Context {
         Route::File {
             old_krate: self.old_krate.clone(),
             old_version: self.old_version.clone(),
-            new_krate: self.new_krate.clone(),
-            new_version: self.new_version.clone(),
+            new_krate: self.new_krate.clone().into(),
+            new_version: self.new_version.clone().into(),
             path,
         }
         .simplify()
diff --git a/src/lib.rs b/src/lib.rs
index 03844de..4a376a4 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -8,6 +8,7 @@
 mod cache;
 pub mod components;
 mod data;
+mod maybe_parsed;
 mod syntax;
 #[cfg(test)]
 mod tests;
@@ -15,6 +16,7 @@ mod version;
 pub mod views;
 
 use crate::{
+    maybe_parsed::MaybeParsed,
     version::{VersionId, VersionNamed},
     views::*,
 };
@@ -92,8 +94,13 @@ pub enum Route {
     File {
         old_krate: String,
         old_version: VersionId,
-        new_krate: String,
-        new_version: VersionId,
+        // Handling of `/` in wildcard fields changed in yew-router-0.20 and route
+        // recognizer can match this handler instead of SingleSourceFile.
+        //
+        // The following two fields are parsed optionally and then routed manually in
+        // Route::render method.
+        new_krate: MaybeParsed<VersionId>,
+        new_version: MaybeParsed<VersionId>,
         path: Utf8PathBuf,
     },
 
@@ -177,9 +184,27 @@ impl Route {
                 new_krate,
                 new_version,
                 path,
-            } => html! {
-                <Diff src_name={old_krate} dst_name={new_krate} old={old_version} new={new_version} {path} />
-            },
+            } => {
+                // Route manually to keep compatibility with old links.
+                match (new_krate, new_version) {
+                    (MaybeParsed::String(new_krate), MaybeParsed::Parsed(new_version)) => {
+                        // matched /:old_krate/:old_version/:new_krate/:new_version/*path
+                        html! {
+                            <Diff src_name={old_krate} dst_name={new_krate} old={old_version} new={new_version} {path} />
+                        }
+                    }
+                    (MaybeParsed::Parsed(new_version), root) => {
+                        // matched /:krate/:old_version/:new_version/:root/*path
+                        Route::render(Route::SingleSourceFile {
+                            krate: old_krate,
+                            old_version,
+                            new_version,
+                            path: Utf8PathBuf::from(String::from(root)).join(path),
+                        })
+                    }
+                    _ => Route::render(Route::NotFound),
+                }
+            }
             Route::NotFound => html! { <NotFound /> },
             Route::Search { query } => html! { <Search search={query} /> },
             Route::RepoFile {
@@ -201,8 +226,8 @@ impl Route {
             Route::File {
                 old_krate,
                 old_version,
-                new_krate,
-                new_version,
+                new_krate: MaybeParsed::String(new_krate),
+                new_version: MaybeParsed::Parsed(new_version),
                 path,
             } if old_krate == new_krate => Route::SingleSourceFile {
                 krate: old_krate,
diff --git a/src/maybe_parsed.rs b/src/maybe_parsed.rs
new file mode 100644
index 0000000..0b4745c
--- /dev/null
+++ b/src/maybe_parsed.rs
@@ -0,0 +1,59 @@
+use std::{
+    convert::Infallible,
+    fmt::{Display, Formatter, Result as FmtResult},
+    str::FromStr,
+};
+
+use crate::version::VersionId;
+
+#[derive(Clone, PartialEq)]
+pub enum MaybeParsed<T> {
+    Parsed(T),
+    String(String),
+}
+
+impl<T: FromStr> FromStr for MaybeParsed<T> {
+    type Err = Infallible;
+
+    fn from_str(input: &str) -> Result<Self, Self::Err> {
+        Ok(T::from_str(input)
+            .map(Self::Parsed)
+            .unwrap_or_else(|_| MaybeParsed::String(input.to_string())))
+    }
+}
+
+impl<T: Display> Display for MaybeParsed<T> {
+    fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
+        match self {
+            Self::Parsed(i) => i.fmt(f),
+            Self::String(i) => i.fmt(f),
+        }
+    }
+}
+
+impl<T: ToString> From<MaybeParsed<T>> for String {
+    fn from(value: MaybeParsed<T>) -> Self {
+        match value {
+            MaybeParsed::Parsed(i) => i.to_string(),
+            MaybeParsed::String(i) => i,
+        }
+    }
+}
+
+impl<T> From<String> for MaybeParsed<T> {
+    fn from(value: String) -> Self {
+        Self::String(value)
+    }
+}
+
+impl From<semver::Version> for MaybeParsed<VersionId> {
+    fn from(value: semver::Version) -> Self {
+        Self::Parsed(value.into())
+    }
+}
+
+impl From<VersionId> for MaybeParsed<VersionId> {
+    fn from(value: VersionId) -> Self {
+        Self::Parsed(value)
+    }
+}
diff --git a/src/views/diff.rs b/src/views/diff.rs
index 97719bc..d773e2d 100644
--- a/src/views/diff.rs
+++ b/src/views/diff.rs
@@ -206,7 +206,7 @@ fn SourceFetcherInner(props: &SourceFetcherProps) -> HtmlResult {
                         move |((src_name, old), (dst_name, new)): ((String, Version), (String, Version))| {
                             navigator.push(&Route::File {
                                 old_krate: src_name.clone(),
-                                new_krate: dst_name.clone(),
+                                new_krate: dst_name.clone().into(),
                                 old_version: old.clone().into(),
                                 new_version: new.clone().into(),
                                 path: path.clone().unwrap_or_default().into(),
@@ -230,7 +230,7 @@ fn SourceFetcherInner(props: &SourceFetcherProps) -> HtmlResult {
             return Ok(html! {
                 <Redirect<Route> to={Route::File {
                     old_krate: props.src_info.krate.id.clone(),
-                    new_krate: props.dst_info.krate.id.clone(),
+                    new_krate: props.dst_info.krate.id.clone().into(),
                     old_version: props.old.version.clone().into(),
                     new_version: props.new.version.clone().into(),
                     path: "Cargo.toml".into(),
@@ -283,7 +283,7 @@ pub fn SourceView(props: &SourceViewProps) -> Html {
                     move |((src_name, old), (dst_name, new)): ((String, Version), (String, Version))| {
                         navigator.push(&Route::File {
                             old_krate: src_name.clone(),
-                            new_krate: dst_name.clone(),
+                            new_krate: dst_name.clone().into(),
                             old_version: old.clone().into(),
                             new_version: new.clone().into(),
                             path: path.clone(),