diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 57c48cc2f..5e784a346 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -2,7 +2,7 @@ env:
   RUSTFLAGS: -D warnings
   # coverage collection depends on unstable features.
   # we want the CI results to all be from the same toolchain, so we set it up here.
-  RUSTUP_TOOLCHAIN: nightly-2021-03-24
+  RUSTUP_TOOLCHAIN: nightly-2021-10-30
 on:
   push:
     branches:
@@ -19,13 +19,6 @@ jobs:
     steps:
     - uses: actions/checkout@master
     - run: rustup install ${{ env.RUSTUP_TOOLCHAIN }}
-    - name: ensure lockfile up to date
-      run: cargo generate-lockfile --manifest-path ofl/Cargo.toml
-    - name: install gnu tar to work around https://github.com/actions/cache/issues/403
-      if: matrix.os == 'macos-latest'
-      run: |
-        brew install gnu-tar
-        echo PATH="/usr/local/opt/gnu-tar/libexec/gnubin:$PATH" >> $GITHUB_ENV
     - uses: actions/cache@v2
       with:
         key: ${{ runner.os }}-ofl-${{ hashFiles('ofl/Cargo.lock') }}-${{ env.RUSTUP_TOOLCHAIN }}-2
@@ -62,11 +55,6 @@ jobs:
 
     - name: ensure lockfile up to date
       run: cargo generate-lockfile
-    - name: install gnu tar to work around https://github.com/actions/cache/issues/403
-      if: matrix.os == 'macos-latest'
-      run: |
-        brew install gnu-tar
-        echo PATH="/usr/local/opt/gnu-tar/libexec/gnubin:$PATH" >> $GITHUB_ENV
     - uses: actions/cache@v2
       with:
         key: ${{ runner.os }}-coverage-${{ hashFiles('Cargo.lock') }}-${{ env.RUSTUP_TOOLCHAIN }}-2
@@ -105,11 +93,6 @@ jobs:
 
     - name: ensure lockfile up to date
       run: cargo generate-lockfile
-    - name: install gnu tar to work around https://github.com/actions/cache/issues/403
-      if: matrix.os == 'macos-latest'
-      run: |
-        brew install gnu-tar
-        echo PATH="/usr/local/opt/gnu-tar/libexec/gnubin:$PATH" >> $GITHUB_ENV
     - uses: actions/cache@v2
       with:
         key: ${{ runner.os }}-dom-${{ hashFiles('Cargo.lock') }}-${{ env.RUSTUP_TOOLCHAIN }}-2
@@ -152,11 +135,6 @@ jobs:
 
     - name: ensure lockfile up to date
       run: cargo generate-lockfile
-    - name: install gnu tar to work around https://github.com/actions/cache/issues/403
-      if: matrix.os == 'macos-latest'
-      run: |
-        brew install gnu-tar
-        echo PATH="/usr/local/opt/gnu-tar/libexec/gnubin:$PATH" >> $GITHUB_ENV
     - uses: actions/cache@v2
       with:
         key: ${{ runner.os }}-website-${{ hashFiles('Cargo.lock') }}-${{ env.RUSTUP_TOOLCHAIN }}-2
diff --git a/dom/augdom/src/rsdom.rs b/dom/augdom/src/rsdom.rs
index bc97f2a60..c8997d007 100644
--- a/dom/augdom/src/rsdom.rs
+++ b/dom/augdom/src/rsdom.rs
@@ -64,7 +64,7 @@ impl crate::Dom for Rc<VirtNode> {
             }
             VirtData::Text(t) => {
                 writer
-                    .write_event(Event::Text(BytesText::from_plain_str(&t)))
+                    .write_event(Event::Text(BytesText::from_plain_str(t)))
                     .expect("writing text node");
             }
         }
diff --git a/dom/prettiest/src/lib.rs b/dom/prettiest/src/lib.rs
index abf1cc828..7177357d5 100644
--- a/dom/prettiest/src/lib.rs
+++ b/dom/prettiest/src/lib.rs
@@ -161,7 +161,7 @@ impl Debug for Prettified {
                         continue;
                     }
 
-                    if let Ok(value) = Reflect::get(&obj, &raw_key) {
+                    if let Ok(value) = Reflect::get(obj, &raw_key) {
                         props_seen.insert(key.clone());
                         if value.is_function() {
                             functions.insert(key);
diff --git a/dom/src/embed.rs b/dom/src/embed.rs
index c0bc194c3..4474e6a49 100644
--- a/dom/src/embed.rs
+++ b/dom/src/embed.rs
@@ -30,6 +30,7 @@ impl DomLoop {
 
         let mut inner = RunLoop::new(Box::new(move || {
             let parent = CachedNode::new(parent.clone());
+            #[allow(clippy::redundant_closure)] // removing the closure syntax makes this FnOnce
             let new_root = topo::call(|| root());
 
             parent.ensure_child_attached(new_root.to_bind());
diff --git a/mox/src/lib.rs b/mox/src/lib.rs
index 528ac5250..8b6614e87 100644
--- a/mox/src/lib.rs
+++ b/mox/src/lib.rs
@@ -375,7 +375,7 @@ impl ToTokens for MoxExpr {
 trait NodeConvertError {
     fn node_convert_error(node: &syn_rsx::Node) -> syn::Error {
         syn::Error::new(
-            node_span(&node),
+            node_span(node),
             format_args!("Cannot convert {} to {}", node.node_type, std::any::type_name::<Self>(),),
         )
     }
diff --git a/ofl/src/coverage.rs b/ofl/src/coverage.rs
index 12f996184..86e9d1c85 100644
--- a/ofl/src/coverage.rs
+++ b/ofl/src/coverage.rs
@@ -74,7 +74,7 @@ impl Collect {
     pub fn run(&self, project_root: impl AsRef<Path>) -> Result<(), Error> {
         let mut command = Command::new("cargo");
         command
-            .env("RUSTFLAGS", "-Zinstrument-coverage")
+            .env("RUSTFLAGS", "-Zinstrument-coverage -Ccodegen-units=1")
             .env(
                 "LLVM_PROFILE_FILE",
                 project_root
diff --git a/ofl/src/server/inject.rs b/ofl/src/server/inject.rs
index 374ca4724..77cbaf93c 100644
--- a/ofl/src/server/inject.rs
+++ b/ofl/src/server/inject.rs
@@ -40,7 +40,7 @@ where
 
 fn inject_script_tag(body: &str) -> Option<String> {
     lol_html::rewrite_str(
-        &body,
+        body,
         RewriteStrSettings {
             element_content_handlers: vec![element!("head", |head| {
                 info!("inserting script tag");
diff --git a/ofl/src/versions.rs b/ofl/src/versions.rs
index 4ff7486cd..eae198cec 100644
--- a/ofl/src/versions.rs
+++ b/ofl/src/versions.rs
@@ -135,14 +135,14 @@ fn update_dependency_version<'doc>(
     }
 
     let dep_version: &mut toml_edit::Value =
-        if let Some(dep) = dependencies[&package_name].as_table_mut() {
+        if let Some(dep) = dependencies[package_name].as_table_mut() {
             if dep.contains_key("version") {
                 dep["version"].as_value_mut().unwrap()
             } else {
                 // it's a table but it only specifies path or something else weird
                 return false;
             }
-        } else if let Some(dep) = dependencies[&package_name].as_value_mut() {
+        } else if let Some(dep) = dependencies[package_name].as_value_mut() {
             if let Some(inline) = dep.as_inline_table_mut() {
                 if let Some(version) = inline.get_mut("version") {
                     version
diff --git a/src/runtime/var.rs b/src/runtime/var.rs
index e9334464b..864d71f3e 100644
--- a/src/runtime/var.rs
+++ b/src/runtime/var.rs
@@ -33,7 +33,7 @@ impl<State> Var<State> {
 
     /// Returns a reference to the latest value, pending or committed.
     pub fn latest(&self) -> &State {
-        &self.pending.as_ref().unwrap_or(&self.current)
+        self.pending.as_ref().unwrap_or(&self.current)
     }
 
     /// Initiate a commit to the state variable. The commit will actually
diff --git a/topo/src/lib.rs b/topo/src/lib.rs
index a86f3832b..9db2729fe 100644
--- a/topo/src/lib.rs
+++ b/topo/src/lib.rs
@@ -474,8 +474,6 @@ impl From<&'static Location<'static>> for Callsite {
 struct Scope {
     /// current id
     id: CallId,
-    /// source location for this scope's root
-    callsite: Callsite,
     /// # times each callsite's type has been observed during this scope.
     callsite_counts: RefCell<Vec<(Callsite, u32)>>,
 }
@@ -491,7 +489,6 @@ impl Scope {
     {
         self.increment_count(callsite);
         let child_point = Self {
-            callsite,
             callsite_counts: RefCell::new(Default::default()),
             id: self.id.child(callsite, slot),
         };
@@ -523,7 +520,7 @@ impl Scope {
 
 impl Default for Scope {
     fn default() -> Self {
-        Self { id: CallId::root(), callsite: Callsite::here(), callsite_counts: Default::default() }
+        Self { id: CallId::root(), callsite_counts: Default::default() }
     }
 }