diff --git a/crates/cargo-platform/src/error.rs b/crates/cargo-platform/src/error.rs
index bf4b35f27..2d5b315f9 100644
--- a/crates/cargo-platform/src/error.rs
+++ b/crates/cargo-platform/src/error.rs
@@ -21,7 +21,7 @@ pub enum ParseErrorKind {
 }
 
 impl fmt::Display for ParseError {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         write!(
             f,
             "failed to parse `{}` as a cfg expression: {}",
@@ -31,7 +31,7 @@ impl fmt::Display for ParseError {
 }
 
 impl fmt::Display for ParseErrorKind {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         use ParseErrorKind::*;
         match self {
             UnterminatedString => write!(f, "unterminated string in cfg"),
diff --git a/crates/cargo-test-macro/src/lib.rs b/crates/cargo-test-macro/src/lib.rs
index aa06f477d..937fbce6b 100644
--- a/crates/cargo-test-macro/src/lib.rs
+++ b/crates/cargo-test-macro/src/lib.rs
@@ -1,5 +1,3 @@
-extern crate proc_macro;
-
 use proc_macro::*;
 use std::process::Command;
 use std::sync::Once;
diff --git a/crates/cargo-test-support/src/registry.rs b/crates/cargo-test-support/src/registry.rs
index 05af009ce..f70bacf04 100644
--- a/crates/cargo-test-support/src/registry.rs
+++ b/crates/cargo-test-support/src/registry.rs
@@ -790,7 +790,7 @@ impl HttpServer {
         }
     }
 
-    fn check_authorized(&self, req: &Request, mutation: Option<Mutation>) -> bool {
+    fn check_authorized(&self, req: &Request, mutation: Option<Mutation<'_>>) -> bool {
         let (private_key, private_key_subject) = if mutation.is_some() || self.auth_required {
             match &self.token {
                 Token::Plaintext(token) => return Some(token) == req.authorization.as_ref(),
@@ -832,7 +832,8 @@ impl HttpServer {
             url: &'a str,
             kip: &'a str,
         }
-        let footer: Footer = t!(serde_json::from_slice(untrusted_token.untrusted_footer()).ok());
+        let footer: Footer<'_> =
+            t!(serde_json::from_slice(untrusted_token.untrusted_footer()).ok());
         if footer.kip != paserk_pub_key_id {
             return false;
         }
@@ -861,7 +862,7 @@ impl HttpServer {
             _challenge: Option<&'a str>, // todo: PASETO with challenges
             v: Option<u8>,
         }
-        let message: Message = t!(serde_json::from_str(trusted_token.payload()).ok());
+        let message: Message<'_> = t!(serde_json::from_str(trusted_token.payload()).ok());
         let token_time = t!(OffsetDateTime::parse(message.iat, &Rfc3339).ok());
         let now = OffsetDateTime::now_utc();
         if (now - token_time) > Duration::MINUTE {
diff --git a/crates/mdman/src/hbs.rs b/crates/mdman/src/hbs.rs
index 81ad7ee45..055eb3f28 100644
--- a/crates/mdman/src/hbs.rs
+++ b/crates/mdman/src/hbs.rs
@@ -12,7 +12,7 @@ use std::path::Path;
 type FormatterRef<'a> = &'a (dyn Formatter + Send + Sync);
 
 /// Processes the handlebars template at the given file.
-pub fn expand(file: &Path, formatter: FormatterRef) -> Result<String, Error> {
+pub fn expand(file: &Path, formatter: FormatterRef<'_>) -> Result<String, Error> {
     let mut handlebars = Handlebars::new();
     handlebars.set_strict_mode(true);
     handlebars.register_helper("lower", Box::new(lower));
@@ -174,10 +174,10 @@ impl HelperDef for ManLinkHelper<'_> {
 ///
 /// This sets a variable to a value within the template context.
 fn set_decorator(
-    d: &Decorator,
-    _: &Handlebars,
+    d: &Decorator<'_, '_>,
+    _: &Handlebars<'_>,
     _ctx: &Context,
-    rc: &mut RenderContext,
+    rc: &mut RenderContext<'_, '_>,
 ) -> Result<(), RenderError> {
     let data_to_set = d.hash();
     for (k, v) in data_to_set {
@@ -187,7 +187,7 @@ fn set_decorator(
 }
 
 /// Sets a variable to a value within the context.
-fn set_in_context(rc: &mut RenderContext, key: &str, value: serde_json::Value) {
+fn set_in_context(rc: &mut RenderContext<'_, '_>, key: &str, value: serde_json::Value) {
     let mut ctx = match rc.context() {
         Some(c) => (*c).clone(),
         None => Context::wraps(serde_json::Value::Object(serde_json::Map::new())).unwrap(),
@@ -201,7 +201,7 @@ fn set_in_context(rc: &mut RenderContext, key: &str, value: serde_json::Value) {
 }
 
 /// Removes a variable from the context.
-fn remove_from_context(rc: &mut RenderContext, key: &str) {
+fn remove_from_context(rc: &mut RenderContext<'_, '_>, key: &str) {
     let ctx = rc.context().expect("cannot remove from null context");
     let mut ctx = (*ctx).clone();
     if let serde_json::Value::Object(m) = ctx.data_mut() {
diff --git a/crates/mdman/src/lib.rs b/crates/mdman/src/lib.rs
index 01c3c8d31..5cfb3f4ca 100644
--- a/crates/mdman/src/lib.rs
+++ b/crates/mdman/src/lib.rs
@@ -64,7 +64,7 @@ pub fn convert(
 type EventIter<'a> = Box<dyn Iterator<Item = (Event<'a>, Range<usize>)> + 'a>;
 
 /// Creates a new markdown parser with the given input.
-pub(crate) fn md_parser(input: &str, url: Option<Url>) -> EventIter {
+pub(crate) fn md_parser(input: &str, url: Option<Url>) -> EventIter<'_> {
     let mut options = Options::empty();
     options.insert(Options::ENABLE_TABLES);
     options.insert(Options::ENABLE_FOOTNOTES);
diff --git a/crates/xtask-bump-check/src/xtask.rs b/crates/xtask-bump-check/src/xtask.rs
index c50d51efd..5af9491bb 100644
--- a/crates/xtask-bump-check/src/xtask.rs
+++ b/crates/xtask-bump-check/src/xtask.rs
@@ -105,7 +105,7 @@ fn config_configure(config: &mut Config, args: &ArgMatches) -> CliResult {
 /// Main entry of `xtask-bump-check`.
 ///
 /// Assumption: version number are incremental. We never have point release for old versions.
-fn bump_check(args: &clap::ArgMatches, config: &mut cargo::util::Config) -> CargoResult<()> {
+fn bump_check(args: &clap::ArgMatches, config: &cargo::util::Config) -> CargoResult<()> {
     let ws = args.workspace(config)?;
     let repo = git2::Repository::open(ws.root())?;
     let base_commit = get_base_commit(config, args, &repo)?;
@@ -184,7 +184,7 @@ fn bump_check(args: &clap::ArgMatches, config: &mut cargo::util::Config) -> Carg
 
     status("no version bump needed for member crates.")?;
 
-    return Ok(());
+    Ok(())
 }
 
 /// Returns the commit of upstream `master` branch if `base-rev` is missing.
@@ -256,7 +256,7 @@ fn get_referenced_commit<'a>(
     repo: &'a git2::Repository,
     base: &git2::Commit<'a>,
 ) -> CargoResult<Option<git2::Commit<'a>>> {
-    let [beta, stable] = beta_and_stable_branch(&repo)?;
+    let [beta, stable] = beta_and_stable_branch(repo)?;
     let rev_id = base.id();
     let stable_commit = stable.get().peel_to_commit()?;
     let beta_commit = beta.get().peel_to_commit()?;
diff --git a/credential/cargo-credential-1password/src/main.rs b/credential/cargo-credential-1password/src/main.rs
index a2607fd2f..921b52145 100644
--- a/credential/cargo-credential-1password/src/main.rs
+++ b/credential/cargo-credential-1password/src/main.rs
@@ -255,8 +255,8 @@ pub struct OnePasswordCredential {}
 impl Credential for OnePasswordCredential {
     fn perform(
         &self,
-        registry: &RegistryInfo,
-        action: &Action,
+        registry: &RegistryInfo<'_>,
+        action: &Action<'_>,
         args: &[&str],
     ) -> Result<CredentialResponse, Error> {
         let op = OnePasswordKeychain::new(args)?;
diff --git a/credential/cargo-credential-libsecret/src/lib.rs b/credential/cargo-credential-libsecret/src/lib.rs
index f83b424ee..ee1797605 100644
--- a/credential/cargo-credential-libsecret/src/lib.rs
+++ b/credential/cargo-credential-libsecret/src/lib.rs
@@ -104,16 +104,16 @@ mod linux {
     impl Credential for LibSecretCredential {
         fn perform(
             &self,
-            registry: &RegistryInfo,
-            action: &Action,
+            registry: &RegistryInfo<'_>,
+            action: &Action<'_>,
             _args: &[&str],
         ) -> Result<CredentialResponse, Error> {
             // Dynamically load libsecret to avoid users needing to install
             // additional -dev packages when building this provider.
             let lib;
-            let secret_password_lookup_sync: Symbol<SecretPasswordLookupSync>;
-            let secret_password_store_sync: Symbol<SecretPasswordStoreSync>;
-            let secret_password_clear_sync: Symbol<SecretPasswordClearSync>;
+            let secret_password_lookup_sync: Symbol<'_, SecretPasswordLookupSync>;
+            let secret_password_store_sync: Symbol<'_, SecretPasswordStoreSync>;
+            let secret_password_clear_sync: Symbol<'_, SecretPasswordClearSync>;
             unsafe {
                 lib = Library::new("libsecret-1.so").context(
                     "failed to load libsecret: try installing the `libsecret` \
diff --git a/credential/cargo-credential-wincred/src/lib.rs b/credential/cargo-credential-wincred/src/lib.rs
index 9200ca58f..24b072ee2 100644
--- a/credential/cargo-credential-wincred/src/lib.rs
+++ b/credential/cargo-credential-wincred/src/lib.rs
@@ -38,8 +38,8 @@ mod win {
     impl Credential for WindowsCredential {
         fn perform(
             &self,
-            registry: &RegistryInfo,
-            action: &Action,
+            registry: &RegistryInfo<'_>,
+            action: &Action<'_>,
             _args: &[&str],
         ) -> Result<CredentialResponse, Error> {
             match action {
diff --git a/credential/cargo-credential/examples/file-provider.rs b/credential/cargo-credential/examples/file-provider.rs
index d11958536..3ed312cb8 100644
--- a/credential/cargo-credential/examples/file-provider.rs
+++ b/credential/cargo-credential/examples/file-provider.rs
@@ -12,8 +12,8 @@ struct FileCredential;
 impl Credential for FileCredential {
     fn perform(
         &self,
-        registry: &RegistryInfo,
-        action: &Action,
+        registry: &RegistryInfo<'_>,
+        action: &Action<'_>,
         _args: &[&str],
     ) -> Result<CredentialResponse, cargo_credential::Error> {
         if registry.index_url != "https://github.com/rust-lang/crates.io-index" {
diff --git a/credential/cargo-credential/examples/stdout-redirected.rs b/credential/cargo-credential/examples/stdout-redirected.rs
index 0b9bcc2f7..75a2d16d1 100644
--- a/credential/cargo-credential/examples/stdout-redirected.rs
+++ b/credential/cargo-credential/examples/stdout-redirected.rs
@@ -7,8 +7,8 @@ struct MyCredential;
 impl Credential for MyCredential {
     fn perform(
         &self,
-        _registry: &RegistryInfo,
-        _action: &Action,
+        _registry: &RegistryInfo<'_>,
+        _action: &Action<'_>,
         _args: &[&str],
     ) -> Result<CredentialResponse, Error> {
         // Informational messages should be sent on stderr.
diff --git a/credential/cargo-credential/src/lib.rs b/credential/cargo-credential/src/lib.rs
index 85ff9919e..60bce65be 100644
--- a/credential/cargo-credential/src/lib.rs
+++ b/credential/cargo-credential/src/lib.rs
@@ -61,8 +61,8 @@ pub struct UnsupportedCredential;
 impl Credential for UnsupportedCredential {
     fn perform(
         &self,
-        _registry: &RegistryInfo,
-        _action: &Action,
+        _registry: &RegistryInfo<'_>,
+        _action: &Action<'_>,
         _args: &[&str],
     ) -> Result<CredentialResponse, Error> {
         Err(Error::UrlNotSupported)
@@ -215,8 +215,8 @@ pub trait Credential {
     /// Retrieves a token for the given registry.
     fn perform(
         &self,
-        registry: &RegistryInfo,
-        action: &Action,
+        registry: &RegistryInfo<'_>,
+        action: &Action<'_>,
         args: &[&str],
     ) -> Result<CredentialResponse, Error>;
 }
@@ -260,7 +260,7 @@ fn doit(
 fn deserialize_request(
     value: &str,
 ) -> Result<CredentialRequest<'_>, Box<dyn std::error::Error + Send + Sync>> {
-    let request: CredentialRequest = serde_json::from_str(&value)?;
+    let request: CredentialRequest<'_> = serde_json::from_str(&value)?;
     if request.v != PROTOCOL_VERSION_1 {
         return Err(format!("unsupported protocol version {}", request.v).into());
     }
@@ -276,8 +276,8 @@ pub fn read_line() -> Result<String, io::Error> {
 
 /// Prompt the user for a token.
 pub fn read_token(
-    login_options: &LoginOptions,
-    registry: &RegistryInfo,
+    login_options: &LoginOptions<'_>,
+    registry: &RegistryInfo<'_>,
 ) -> Result<Secret<String>, Error> {
     if let Some(token) = &login_options.token {
         return Ok(token.to_owned());
@@ -387,7 +387,7 @@ mod tests {
             r#"{"v":1,"registry":{"index-url":"url"},"kind":"get","operation":"owners","name":"pkg"}"#
         );
 
-        let cr: CredentialRequest =
+        let cr: CredentialRequest<'_> =
             serde_json::from_str(r#"{"extra-1":true,"v":1,"registry":{"index-url":"url","extra-2":true},"kind":"get","operation":"owners","name":"pkg","args":[]}"#).unwrap();
         assert_eq!(cr, get_oweners);
     }
@@ -405,7 +405,7 @@ mod tests {
             action: Action::Logout,
         };
 
-        let cr: CredentialRequest = serde_json::from_str(
+        let cr: CredentialRequest<'_> = serde_json::from_str(
             r#"{"v":1,"registry":{"index-url":"url"},"kind":"logout","extra-1":true,"args":[]}"#,
         )
         .unwrap();
@@ -425,7 +425,7 @@ mod tests {
             action: Action::Unknown,
         };
 
-        let cr: CredentialRequest = serde_json::from_str(
+        let cr: CredentialRequest<'_> = serde_json::from_str(
             r#"{"v":1,"registry":{"index-url":""},"kind":"unexpected-1","extra-1":true,"args":[]}"#,
         )
         .unwrap();