diff --git a/Cargo.lock b/Cargo.lock
index 62844413d..cac350be8 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2,18 +2,6 @@
 # It is not intended for manual editing.
 version = 3
 
-[[package]]
-name = "ahash"
-version = "0.8.11"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e89da841a80418a9b391ebaea17f5c112ffaaa96f621d2c285b5174da76b9011"
-dependencies = [
- "cfg-if",
- "once_cell",
- "version_check",
- "zerocopy",
-]
-
 [[package]]
 name = "allocator-api2"
 version = "0.2.18"
@@ -22,9 +10,9 @@ checksum = "5c6cb57a04249c6480766f7f7cef5467412af1490f8d1e243141daddada3264f"
 
 [[package]]
 name = "autocfg"
-version = "1.3.0"
+version = "1.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0c4b4d0bd25bd0b74681c0ad21497610ce1b7c91b1022cd21c80c6fbdd9476b0"
+checksum = "ace50bade8e6234aa140d9a2f552bbee1db4d353f69b8217bc503490fc1a9f26"
 
 [[package]]
 name = "bitflags"
@@ -32,17 +20,11 @@ version = "2.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b048fb63fd8b5923fc5aa7b340d8e156aec7ec02f0c78fa8a6ddc2613f6f71de"
 
-[[package]]
-name = "byteorder"
-version = "1.5.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1fd0f2584146f6f2ef48085050886acf353beff7305ebd1ae69500e27c67f64b"
-
 [[package]]
 name = "cc"
-version = "1.1.21"
+version = "1.1.30"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "07b1695e2c7e8fc85310cde85aeaab7e3097f593c91d209d3f9df76c928100f0"
+checksum = "b16803a61b81d9eabb7eae2588776c4c1e584b738ede45fdbb4c972cec1e9945"
 dependencies = [
  "jobserver",
  "libc",
@@ -68,12 +50,18 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "978747c1d849a7d2ee5e8adc0159961c48fb7e5db2f06af6723b80123bb53856"
 dependencies = [
  "cfg-if",
- "hashbrown",
+ "hashbrown 0.14.5",
  "lock_api",
  "once_cell",
  "parking_lot_core",
 ]
 
+[[package]]
+name = "equivalent"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5443807d6dff69373d433ab9ef5378ad8df50ca6298caf15de6e52e24aaf54d5"
+
 [[package]]
 name = "errno"
 version = "0.3.9"
@@ -101,7 +89,6 @@ dependencies = [
  "pcre2",
  "portable-atomic",
  "rand",
- "rand_pcg",
  "rsconf",
  "serial_test",
  "terminfo",
@@ -123,24 +110,26 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3f9eec918d3f24069decb9af1554cad7c880e2da24a9afd88aca000531ab82c1"
 
 [[package]]
-name = "getrandom"
-version = "0.2.15"
+name = "foldhash"
+version = "0.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c4567c8db10ae91089c99af84c68c38da3ec2f087c3f82960bcdbf3656b6f4d7"
-dependencies = [
- "cfg-if",
- "libc",
- "wasi",
-]
+checksum = "f81ec6369c545a7d40e4589b5597581fa1c441fe1cce96dd1de43159910a36a2"
 
 [[package]]
 name = "hashbrown"
 version = "0.14.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e5274423e17b7c9fc20b6e7e208532f9b19825d82dfd615708b70edd83df41f1"
+
+[[package]]
+name = "hashbrown"
+version = "0.15.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1e087f84d4f86bf4b218b927129862374b72199ae7d8657835f1e89000eea4fb"
 dependencies = [
- "ahash",
  "allocator-api2",
+ "equivalent",
+ "foldhash",
 ]
 
 [[package]]
@@ -160,9 +149,9 @@ checksum = "bbd2bcb4c963f2ddae06a2efc7e9f3591312473c50c6685e1f298068316e66fe"
 
 [[package]]
 name = "libc"
-version = "0.2.158"
+version = "0.2.159"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d8adc4bb1803a324070e64a98ae98f38934d91957a99cfb3a43dcbc01bc56439"
+checksum = "561d97a539a36e26a9a5fad1ea11a3039a67714694aaa379433e580854bc3dc5"
 
 [[package]]
 name = "lock_api"
@@ -182,11 +171,11 @@ checksum = "a7a70ba024b9dc04c27ea2f0c0548feb474ec5c54bba33a7f72f873a39d07b24"
 
 [[package]]
 name = "lru"
-version = "0.12.4"
+version = "0.12.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "37ee39891760e7d94734f6f63fedc29a2e4a152f836120753a72503f09fcf904"
+checksum = "234cf4f4a04dc1f57e24b96cc0cd600cf2af460d4161ac5ecdd0af8e1f3b2a38"
 dependencies = [
- "hashbrown",
+ "hashbrown 0.15.0",
 ]
 
 [[package]]
@@ -234,9 +223,9 @@ dependencies = [
 
 [[package]]
 name = "once_cell"
-version = "1.19.0"
+version = "1.20.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3fdb12b2476b595f9358c5161aa467c2438859caa136dec86c26fdd2efe17b92"
+checksum = "1261fe7e33c73b354eab43b1273a57c8f967d0391e80353e51f764ac02cf6775"
 
 [[package]]
 name = "parking_lot"
@@ -321,30 +310,21 @@ dependencies = [
 
 [[package]]
 name = "pkg-config"
-version = "0.3.30"
+version = "0.3.31"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d231b230927b5e4ad203db57bbcbee2802f6bce620b1e4a9024a07d94e2907ec"
+checksum = "953ec861398dccce10c670dfeaf3ec4911ca479e9c02154b3a215178c5f566f2"
 
 [[package]]
 name = "portable-atomic"
-version = "1.8.0"
+version = "1.9.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d30538d42559de6b034bc76fd6dd4c38961b1ee5c6c56e3808c50128fdbc22ce"
-
-[[package]]
-name = "ppv-lite86"
-version = "0.2.20"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "77957b295656769bb8ad2b6a6b09d897d94f05c41b069aede1fcdaa675eaea04"
-dependencies = [
- "zerocopy",
-]
+checksum = "cc9c68a3f6da06753e9335d63e27f6b9754dd1920d941135b7ea8224f141adb2"
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.86"
+version = "1.0.87"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5e719e8df665df0d1c8fbfd238015744736151d4445ec0836b8e628aae103b77"
+checksum = "b3e4daa0dcf6feba26f985457cdf104d4b4256fc5a09547140f3631bb076b19a"
 dependencies = [
  "unicode-ident",
 ]
@@ -364,18 +344,6 @@ version = "0.8.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "34af8d1a0e25924bc5b7c43c079c942339d8f0a8b57c39049bef581b46327404"
 dependencies = [
- "libc",
- "rand_chacha",
- "rand_core",
-]
-
-[[package]]
-name = "rand_chacha"
-version = "0.3.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e6c10a63a0fa32252be49d21e7709d4d4baf8d231c2dbce1eaa8141b9b127d88"
-dependencies = [
- "ppv-lite86",
  "rand_core",
 ]
 
@@ -384,24 +352,12 @@ name = "rand_core"
 version = "0.6.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ec0be4795e2f6a28069bec0b5ff3e2ac9bafc99e6a9a7dc3547996c5c816922c"
-dependencies = [
- "getrandom",
-]
-
-[[package]]
-name = "rand_pcg"
-version = "0.3.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "59cad018caf63deb318e5a4586d99a24424a364f40f1e5778c29aca23f4fc73e"
-dependencies = [
- "rand_core",
-]
 
 [[package]]
 name = "redox_syscall"
-version = "0.5.4"
+version = "0.5.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0884ad60e090bf1345b93da0a5de8923c93884cd03f40dfcfddd3b4bee661853"
+checksum = "9b6dfecf2c74bce2466cabf93f6664d6998a69eb21e39f4207930065b27b771f"
 dependencies = [
  "bitflags",
 ]
@@ -441,7 +397,7 @@ checksum = "079a83df15f85d89a68d64ae1238f142f172b1fa915d0d76b26a7cba1b659a69"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 1.0.109",
+ "syn",
 ]
 
 [[package]]
@@ -473,17 +429,6 @@ dependencies = [
  "unicode-ident",
 ]
 
-[[package]]
-name = "syn"
-version = "2.0.77"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9f35bcdf61fd8e7be6caf75f429fdca8beb3ed76584befb503b1569faee373ed"
-dependencies = [
- "proc-macro2",
- "quote",
- "unicode-ident",
-]
-
 [[package]]
 name = "terminfo"
 version = "0.9.0"
@@ -502,18 +447,6 @@ version = "1.0.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e91b56cd4cadaeb79bbf1a5645f6b4f8dc5bde8834ad5894a8db35fda9efa1fe"
 
-[[package]]
-name = "version_check"
-version = "0.9.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0b928f33d975fc6ad9f86c8f283853ad26bdd5b10b7f1542aa2fa15e2289105a"
-
-[[package]]
-name = "wasi"
-version = "0.11.0+wasi-snapshot-preview1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9c8d87e72b64a3b4db28d11ce29237c246188f4f51057d65a7eab63b7987e423"
-
 [[package]]
 name = "widestring"
 version = "1.1.0"
@@ -592,24 +525,3 @@ name = "windows_x86_64_msvc"
 version = "0.52.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "589f6da84c646204747d1270a2a5661ea66ed1cced2631d546fdfb155959f9ec"
-
-[[package]]
-name = "zerocopy"
-version = "0.7.35"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1b9b4fd18abc82b8136838da5d50bae7bdea537c574d8dc1a34ed098d6c166f0"
-dependencies = [
- "byteorder",
- "zerocopy-derive",
-]
-
-[[package]]
-name = "zerocopy-derive"
-version = "0.7.35"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fa4f8080344d4671fb4e831a13ad1e68092748387dfc4f55e356242fae12ce3e"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn 2.0.77",
-]
diff --git a/Cargo.toml b/Cargo.toml
index fb9b76c0e..a2d559f3f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -45,7 +45,11 @@ nix = { version = "0.29.0", default-features = false, features = [
 num-traits = "0.2.19"
 once_cell = "1.19.0"
 fish-printf = { path = "./printf", features = ["widestring"] }
-rand = { version = "0.8.5", features = ["small_rng"] }
+
+# Don't use the "getrandom" feature as it requires "getentropy" which was not
+# available on macOS < 10.12. We can enable "getrandom" when we raise the
+# minimum supported version to 10.12.
+rand = { version = "0.8.5", default-features = false, features = ["small_rng"] }
 widestring = "1.1.0"
 # We need 0.9.0 specifically for some crash fixes.
 terminfo = "0.9.0"
@@ -56,7 +60,6 @@ portable-atomic = { version = "1", default-features = false, features = [
 ] }
 
 [dev-dependencies]
-rand_pcg = "0.3.1"
 serial_test = { version = "1.0.0", default-features = false }
 
 [build-dependencies]
diff --git a/src/builtins/random.rs b/src/builtins/random.rs
index 4ff31c236..f854aef62 100644
--- a/src/builtins/random.rs
+++ b/src/builtins/random.rs
@@ -1,12 +1,13 @@
 use super::prelude::*;
 
+use crate::util::get_rng;
 use crate::wutil;
 use once_cell::sync::Lazy;
 use rand::rngs::SmallRng;
 use rand::{Rng, SeedableRng};
 use std::sync::Mutex;
 
-static RNG: Lazy<Mutex<SmallRng>> = Lazy::new(|| Mutex::new(SmallRng::from_entropy()));
+static RNG: Lazy<Mutex<SmallRng>> = Lazy::new(|| Mutex::new(get_rng()));
 
 pub fn random(parser: &Parser, streams: &mut IoStreams, argv: &mut [&wstr]) -> Option<c_int> {
     let cmd = argv[0];
diff --git a/src/history.rs b/src/history.rs
index 50ab39a27..1a22fd9d6 100644
--- a/src/history.rs
+++ b/src/history.rs
@@ -63,7 +63,7 @@ use crate::{
         path_get_config, path_get_data, path_get_data_remoteness, path_is_valid, DirRemoteness,
     },
     threads::{assert_is_background_thread, iothread_perform},
-    util::find_subslice,
+    util::{find_subslice, get_rng},
     wchar::prelude::*,
     wcstringutil::subsequence_in_string,
     wildcard::{wildcard_match, ANY_STRING},
@@ -956,7 +956,7 @@ impl HistoryImpl {
         let vacuum_frequency = 25;
         let countdown_to_vacuum = self
             .countdown_to_vacuum
-            .get_or_insert_with(|| rand::thread_rng().gen_range(0..vacuum_frequency));
+            .get_or_insert_with(|| get_rng().gen_range(0..vacuum_frequency));
 
         // Determine if we're going to vacuum.
         let mut vacuum = false;
diff --git a/src/tests/history.rs b/src/tests/history.rs
index 4de19092f..23c9622e8 100644
--- a/src/tests/history.rs
+++ b/src/tests/history.rs
@@ -4,9 +4,11 @@ use crate::history::{self, History, HistoryItem, HistorySearch, PathList, Search
 use crate::path::path_get_data;
 use crate::tests::prelude::*;
 use crate::tests::string_escape::ESCAPE_TEST_CHAR;
+use crate::util::get_rng;
 use crate::wchar::prelude::*;
 use crate::wcstringutil::{string_prefixes_string, string_prefixes_string_case_insensitive};
-use rand::random;
+use rand::rngs::SmallRng;
+use rand::Rng;
 use std::collections::VecDeque;
 use std::ffi::CString;
 use std::io::BufReader;
@@ -27,12 +29,12 @@ fn history_contains(history: &History, txt: &wstr) -> bool {
     false
 }
 
-fn random_string() -> WString {
+fn random_string(rng: &mut SmallRng) -> WString {
     let mut result = WString::new();
-    let max = 1 + random::<usize>() % 32;
+    let max = rng.gen_range(1..=32);
     for _ in 0..max {
-        let c = char::from_u32(u32::try_from(1 + random::<usize>() % ESCAPE_TEST_CHAR).unwrap())
-            .unwrap();
+        let c =
+            char::from_u32(u32::try_from(1 + rng.gen_range(0..ESCAPE_TEST_CHAR)).unwrap()).unwrap();
         result.push(c);
     }
     result
@@ -154,6 +156,7 @@ fn test_history() {
     let mut after: VecDeque<HistoryItem> = VecDeque::new();
     history.clear();
     let max = 100;
+    let mut rng = get_rng();
     for i in 1..=max {
         // Generate a value.
         let mut value = WString::from_str("test item ") + &i.to_wstring()[..];
@@ -164,10 +167,9 @@ fn test_history() {
         }
 
         // Generate some paths.
-        let mut paths = PathList::new();
-        for _ in 0..random::<usize>() % 6 {
-            paths.push(random_string());
-        }
+        let paths: PathList = (0..rng.gen_range(0..6))
+            .map(|_| random_string(&mut rng))
+            .collect();
 
         // Record this item.
         let mut item =
diff --git a/src/tests/string_escape.rs b/src/tests/string_escape.rs
index 35fab6e8e..ba8ee7534 100644
--- a/src/tests/string_escape.rs
+++ b/src/tests/string_escape.rs
@@ -3,10 +3,10 @@ use crate::common::{
     UnescapeStringStyle, ENCODE_DIRECT_BASE, ENCODE_DIRECT_END,
 };
 use crate::locale::LOCALE_LOCK;
+use crate::util::{get_rng_seed, get_seeded_rng};
 use crate::wchar::{wstr, WString, L};
 use crate::wutil::encoding::{wcrtomb, zero_mbstate, AT_LEAST_MB_LEN_MAX};
 use rand::{Rng, RngCore};
-use rand_pcg::Pcg64Mcg;
 
 /// wcs2string is locale-dependent, so ensure we have a multibyte locale
 /// before using it in a test.
@@ -102,7 +102,7 @@ fn test_escape_var() {
 fn escape_test(escape_style: EscapeStringStyle, unescape_style: UnescapeStringStyle) {
     setlocale();
     let seed: u128 = 92348567983274852905629743984572;
-    let mut rng = Pcg64Mcg::new(seed);
+    let mut rng = get_seeded_rng(seed);
 
     let mut random_string = WString::new();
     let mut escaped_string;
@@ -175,10 +175,8 @@ fn str2hex(input: &[u8]) -> String {
 #[test]
 fn test_convert() {
     setlocale();
-    use rand::random;
-
-    let seed: u128 = random::<u128>();
-    let mut rng = Pcg64Mcg::new(seed);
+    let seed = get_rng_seed();
+    let mut rng = get_seeded_rng(seed);
     let mut origin = Vec::new();
 
     for _ in 0..ESCAPE_TEST_COUNT {
diff --git a/src/util.rs b/src/util.rs
index ebef9a55f..e1093a486 100644
--- a/src/util.rs
+++ b/src/util.rs
@@ -1,8 +1,10 @@
 //! Generic utilities library.
 
 use crate::wchar::prelude::*;
+use rand::{rngs::SmallRng, SeedableRng};
 use std::cmp::Ordering;
 use std::time;
+use std::time::{SystemTime, UNIX_EPOCH};
 
 /// Compares two wide character strings with an (arguably) intuitive ordering. This function tries
 /// to order strings in a way which is intuitive to humans with regards to sorting strings
@@ -170,6 +172,27 @@ pub fn get_time() -> i64 {
     }
 }
 
+// Helper to get a small RNG seed, based on nanoseconds.
+pub fn get_rng_seed() -> u128 {
+    // Note we use an explicit seed to avoid the "getrandom" crate, which uses `getentropy()` on macOS which
+    // is not available before macOS 10.12.
+    SystemTime::now()
+        .duration_since(UNIX_EPOCH)
+        .unwrap_or_default()
+        .as_nanos()
+}
+
+// Helper to get a small RNG with a seed.
+pub fn get_seeded_rng(seed: u128) -> SmallRng {
+    let seed = ((seed >> 64) as u64) ^ (seed as u64);
+    SmallRng::seed_from_u64(seed)
+}
+
+// Helper to get a small RNG using the current time.
+pub fn get_rng() -> SmallRng {
+    get_seeded_rng(get_rng_seed())
+}
+
 // Compare the strings to see if they begin with an integer that can be compared and return the
 // result of that comparison.
 fn wcsfilecmp_leading_digits(a: &wstr, b: &wstr) -> (Ordering, usize, usize) {
diff --git a/src/wutil/tests.rs b/src/wutil/tests.rs
index 9ca1a3227..46723affb 100644
--- a/src/wutil/tests.rs
+++ b/src/wutil/tests.rs
@@ -1,7 +1,8 @@
 use crate::fds::AutoCloseFd;
 use crate::tests::prelude::*;
+use crate::util::get_rng;
 use libc::{c_void, O_CREAT, O_RDWR, O_TRUNC, SEEK_SET};
-use rand::random;
+use rand::Rng;
 use std::{ffi::CString, ptr};
 
 use crate::fallback::fish_mkstemp_cloexec;
@@ -63,6 +64,7 @@ fn test_wwrite_to_fd() {
     let _cleanup = test_init();
     let (_fd, filename) =
         fish_mkstemp_cloexec(CString::new("/tmp/fish_test_wwrite.XXXXXX").unwrap()).unwrap();
+    let mut rng = get_rng();
     let sizes = [1, 2, 3, 5, 13, 23, 64, 128, 255, 4096, 4096 * 2];
     for &size in &sizes {
         let fd = AutoCloseFd::new(unsafe {
@@ -71,7 +73,7 @@ fn test_wwrite_to_fd() {
         assert!(fd.is_valid());
         let mut input = WString::new();
         for _i in 0..size {
-            input.push(random());
+            input.push(rng.gen());
         }
 
         let amt = wwrite_to_fd(&input, fd.fd()).unwrap();