diff --git a/Cargo.lock b/Cargo.lock
index cf619001163de2641a82bee6d0dc5f4ff19d2e50..97800ad7f95f1855a1f83cbdfd05a60897a4db0d 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -37,6 +37,17 @@ dependencies = [
  "version_check",
 ]
 
+[[package]]
+name = "ahash"
+version = "0.8.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2c99f64d1e06488f620f932677e24bc6e2897582980441ae90a671415bd7ec2f"
+dependencies = [
+ "cfg-if",
+ "once_cell",
+ "version_check",
+]
+
 [[package]]
 name = "aho-corasick"
 version = "0.7.20"
@@ -603,7 +614,7 @@ version = "0.11.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ab5ef0d4909ef3724cc8cce6ccc8572c5c817592e9285f5464f8e86f8bd3726e"
 dependencies = [
- "ahash",
+ "ahash 0.7.6",
 ]
 
 [[package]]
@@ -612,6 +623,15 @@ version = "0.12.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8a9ee70c43aaf417c914396645a0fa852624801b24ebb7ae78fe8272889ac888"
 
+[[package]]
+name = "hashbrown"
+version = "0.13.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "43a3c133739dddd0d2990f9a4bdf8eb4b21ef50e4851ca85ab661199821d510e"
+dependencies = [
+ "ahash 0.8.3",
+]
+
 [[package]]
 name = "hashlink"
 version = "0.7.0"
@@ -807,11 +827,11 @@ dependencies = [
 
 [[package]]
 name = "lru"
-version = "0.6.6"
+version = "0.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7ea2d928b485416e8908cff2d97d621db22b27f7b3b6729e438bcf42c671ba91"
+checksum = "03f1160296536f10c833a82dca22267d5486734230d47bf00bf435885814ba1e"
 dependencies = [
- "hashbrown 0.11.2",
+ "hashbrown 0.13.2",
 ]
 
 [[package]]
diff --git a/Cargo.toml b/Cargo.toml
index 5569dcf5426bb5ae83a5dd05cd0307f0b2af0a14..ee3f6dca0d4f004e9232830ba16b822ffdbb8771 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -22,7 +22,7 @@ chrono = "0.4.23"
 enumber = "0.3"
 lazy_static = "1"
 libc = "0.2"
-lru = "0.6.6"
+lru = "0.10.0"
 memmem = "0.1"
 memoffset = "0.6"
 # When bumping the version of Sequoia search the code for XXX to find
diff --git a/src/keystore.rs b/src/keystore.rs
index 0d2babc4bdfea807e37ad01783a7b4c62ee5214d..d6b096e143333dbf514cc9b51feedc421085e8e3 100644
--- a/src/keystore.rs
+++ b/src/keystore.rs
@@ -46,7 +46,8 @@ const CACHE_HASH: HashAlgorithm = HashAlgorithm::SHA256;
 
 // The number of entries in the cache.  Do not make this too big since
 // we iterate over the cache to purge stale entries.
-const CERT_CACHE_ENTRIES: usize = 32;
+const CERT_CACHE_ENTRIES: std::num::NonZeroUsize
+    = unsafe { std::num::NonZeroUsize::new_unchecked(32) };
 
 type CertCache = LruCache<Vec<u8>, Cert>;
 
@@ -359,13 +360,14 @@ impl Keystore {
             .map(|(digest, cert)| (digest, cert.fingerprint()))
             .filter(|(_digest, other)| &fpr == other)
             .map(|(digest, _)| digest)
-            .collect::<Vec<_>>();
+            .cloned()
+            .collect::<Vec<Vec<u8>>>();
         if purge.len() > 0 {
             t!("Purging {} stale entries that also map to {}",
                purge.len(), fpr);
         }
         for stale_digest in purge {
-            cache.pop(stale_digest);
+            cache.pop(&stale_digest);
         }
 
         // Add the new entry to the cache.