diff --git a/ci/compat-Cargo.lock b/ci/compat-Cargo.lock
index 90aa22442..acb766fb0 100644
--- a/ci/compat-Cargo.lock
+++ b/ci/compat-Cargo.lock
@@ -4,9 +4,9 @@ version = 3
 
 [[package]]
 name = "addr2line"
-version = "0.20.0"
+version = "0.21.0"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "f4fa78e18c64fce05e902adecd7a5eed15a5e0a3439f7b0e169f0252214865e3"
+checksum = "8a30b2e23b9e17a9f90641c7ab1549cd9b44f296d3ccbf309d2863cfe398a0cb"
 dependencies = [
  "gimli",
 ]
@@ -19,9 +19,9 @@ checksum = "f26201604c87b1e01bd3d98f8d5d9a8fcbb815e8cedb41ffccbeb4bf593a35fe"
 
 [[package]]
 name = "aho-corasick"
-version = "1.0.4"
+version = "1.1.0"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "6748e8def348ed4d14996fa801f4122cd763fff530258cdc03f64b25f89d3a5a"
+checksum = "0f2135563fb5c609d2b2b87c1e8ce7bc41b0b45430fa9661f457981503dd5bf0"
 dependencies = [
  "memchr",
 ]
@@ -55,9 +55,9 @@ checksum = "d468802bab17cbc0cc575e9b053f41e72aa36bfa6b7f55e3529ffa43161b97fa"
 
 [[package]]
 name = "backtrace"
-version = "0.3.68"
+version = "0.3.69"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "4319208da049c43661739c5fade2ba182f09d1dc2299b32298d3a31692b17e12"
+checksum = "2089b7e3f35b9dd2d0ed921ead4f6d318c27680d4a5bd167b3ee120edb105837"
 dependencies = [
  "addr2line",
  "cc",
@@ -82,15 +82,15 @@ checksum = "0d8c1fef690941d3e7788d328517591fecc684c084084702d6ff1641e993699a"
 
 [[package]]
 name = "bumpalo"
-version = "3.13.0"
+version = "3.14.0"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "a3e2c3daef883ecc1b5d58c15adae93470a91d425f3532ba1695849656af3fc1"
+checksum = "7f30e7476521f6f8af1a1c4c0b8cc94f0bee37d91763d0ca2665f299b6cd8aec"
 
 [[package]]
 name = "bytemuck"
-version = "1.13.1"
+version = "1.14.0"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "17febce684fd15d89027105661fec94afb475cb995fbc59d2865198446ba2eea"
+checksum = "374d28ec25809ee0e23827c2ab573d729e293f281dfe393500e7ad618baa61c6"
 
 [[package]]
 name = "calloop"
@@ -481,7 +481,7 @@ checksum = "1a5c6c585bc94aaf2c7b51dd4c2ba22680844aba4c687be581871a6f518c5742"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.29",
+ "syn 2.0.37",
 ]
 
 [[package]]
@@ -531,9 +531,9 @@ dependencies = [
 
 [[package]]
 name = "gimli"
-version = "0.27.3"
+version = "0.28.0"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "b6c80984affa11d98d1b88b66ac8853f143217b399d3c74116778ff8fdb4ed2e"
+checksum = "6fb8d784f27acf97159b40fc4db5ecd8aa23b9ad5ef69cdd136d3bc80665f0c0"
 
 [[package]]
 name = "gl_generator"
@@ -633,12 +633,6 @@ version = "0.14.0"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
 checksum = "2c6201b9ff9fd90a5a3bac2e56a830d0caa509576f0e503818ee82c181b3437a"
 
-[[package]]
-name = "hermit-abi"
-version = "0.3.2"
-source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "443144c8cdadd93ebf52ddb4056d257f5b52c04d3c804e657d19eb73fc33668b"
-
 [[package]]
 name = "ident_case"
 version = "1.0.1"
@@ -696,9 +690,9 @@ checksum = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
 
 [[package]]
 name = "libc"
-version = "0.2.147"
+version = "0.2.148"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "b4668fb0ea861c1df094127ac5f1da3409a82116a4ba74fca2e58ef927159bb3"
+checksum = "9cdc71e17332e86d2e1d38c1f99edcb6288ee11b815fb1a4b049eaa2114d369b"
 
 [[package]]
 name = "libloading"
@@ -747,9 +741,9 @@ dependencies = [
 
 [[package]]
 name = "memchr"
-version = "2.5.0"
+version = "2.6.3"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "2dffe52ecf27772e601905b7522cb4ef790d2cc203488bbd0e2fe85fcb74566d"
+checksum = "8f232d6ef707e1956a43342693d2a31e72989554d58299d7a88738cc95b0d35c"
 
 [[package]]
 name = "memmap2"
@@ -915,9 +909,9 @@ dependencies = [
 
 [[package]]
 name = "num-bigint"
-version = "0.4.3"
+version = "0.4.4"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "f93ab6289c7b344a8a9f60f88d80aa20032336fe78da341afc91c8a2341fc75f"
+checksum = "608e7659b5c3d7cba262d894801b9ec9d00de989e8a82bd4bef91d08da45cdc0"
 dependencies = [
  "autocfg",
  "num-integer",
@@ -975,16 +969,6 @@ dependencies = [
  "autocfg",
 ]
 
-[[package]]
-name = "num_cpus"
-version = "1.16.0"
-source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "4161fcb6d602d4d2081af7c3a45852d875a03dd337a6bfdd6e06407b61342a43"
-dependencies = [
- "hermit-abi",
- "libc",
-]
-
 [[package]]
 name = "num_enum"
 version = "0.5.11"
@@ -1017,9 +1001,9 @@ dependencies = [
 
 [[package]]
 name = "object"
-version = "0.31.1"
+version = "0.32.1"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "8bda667d9f2b5051b8833f59f3bf748b28ef54f850f4fcb389a252aa383866d1"
+checksum = "9cf5f9dd3933bd50a9e1f149ec995f39ae2c496d31fd772c1fd45ebc27e902b0"
 dependencies = [
  "memchr",
 ]
@@ -1105,9 +1089,9 @@ dependencies = [
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.66"
+version = "1.0.67"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "18fb31db3f9bddb2ea821cde30a9f70117e3f119938b5ee630b7403aa6e2ead9"
+checksum = "3d433d9f1a3e8c1263d9456598b16fec66f4acc9a74dacffd35c7bb09b3a1328"
 dependencies = [
  "unicode-ident",
 ]
@@ -1193,7 +1177,6 @@ dependencies = [
  "crossbeam-deque",
  "crossbeam-utils",
  "libc",
- "num_cpus",
  "rand",
  "rand_xorshift",
  "scoped-tls",
@@ -1230,9 +1213,9 @@ dependencies = [
 
 [[package]]
 name = "regex"
-version = "1.9.3"
+version = "1.9.5"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "81bc1d4caf89fac26a70747fe603c130093b53c773888797a6329091246d651a"
+checksum = "697061221ea1b4a94a624f67d0ae2bfe4e22b8a17b6a192afb11046542cc8c47"
 dependencies = [
  "aho-corasick",
  "memchr",
@@ -1242,9 +1225,9 @@ dependencies = [
 
 [[package]]
 name = "regex-automata"
-version = "0.3.6"
+version = "0.3.8"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "fed1ceff11a1dddaee50c9dc8e4938bd106e9d89ae372f192311e7da498e3b69"
+checksum = "c2f401f4955220693b56f8ec66ee9c78abffd8d1c4f23dc41a23839eb88f0795"
 dependencies = [
  "aho-corasick",
  "memchr",
@@ -1253,9 +1236,9 @@ dependencies = [
 
 [[package]]
 name = "regex-syntax"
-version = "0.7.4"
+version = "0.7.5"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "e5ea92a5b6195c6ef2a0295ea818b312502c6fc94dde986c5553242e18fd4ce2"
+checksum = "dbb5fb1acd8a1a18b3dd5be62d25485eb770e05afb408a9627d14d451bae12da"
 
 [[package]]
 name = "rustc-demangle"
@@ -1298,22 +1281,22 @@ dependencies = [
 
 [[package]]
 name = "serde"
-version = "1.0.185"
+version = "1.0.188"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "be9b6f69f1dfd54c3b568ffa45c310d6973a5e5148fd40cf515acaf38cf5bc31"
+checksum = "cf9e0fcba69a370eed61bcf2b728575f726b50b55cba78064753d708ddc7549e"
 dependencies = [
  "serde_derive",
 ]
 
 [[package]]
 name = "serde_derive"
-version = "1.0.185"
+version = "1.0.188"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "dc59dfdcbad1437773485e0367fea4b090a2e0a16d9ffc46af47764536a298ec"
+checksum = "4eca7ac642d82aa35b60049a6eccb4be6be75e599bd2e9adb5f875a737654af2"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.29",
+ "syn 2.0.37",
 ]
 
 [[package]]
@@ -1370,9 +1353,9 @@ checksum = "62bb4feee49fdd9f707ef802e22365a35de4b7b299de4763d44bfea899442ff9"
 
 [[package]]
 name = "smithay-client-toolkit"
-version = "0.16.0"
+version = "0.16.1"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "f307c47d32d2715eb2e0ece5589057820e0e5e70d07c247d1063e844e107f454"
+checksum = "870427e30b8f2cbe64bf43ec4b86e88fe39b0a84b3f15efd9c9c2d020bc86eb9"
 dependencies = [
  "bitflags",
  "calloop",
@@ -1406,9 +1389,9 @@ dependencies = [
 
 [[package]]
 name = "syn"
-version = "2.0.29"
+version = "2.0.37"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "c324c494eba9d92503e6f1ef2e6df781e78f6a7705a0202d9801b198807d518a"
+checksum = "7303ef2c05cd654186cb250d29049a24840ca25d2747c25c0381c8d9e2f582e8"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -1423,22 +1406,22 @@ checksum = "36ae8932fcfea38b7d3883ae2ab357b0d57a02caaa18ebb4f5ece08beaec4aa0"
 
 [[package]]
 name = "thiserror"
-version = "1.0.47"
+version = "1.0.48"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "97a802ec30afc17eee47b2855fc72e0c4cd62be9b4efe6591edde0ec5bd68d8f"
+checksum = "9d6d7a740b8a666a7e828dd00da9c0dc290dff53154ea77ac109281de90589b7"
 dependencies = [
  "thiserror-impl",
 ]
 
 [[package]]
 name = "thiserror-impl"
-version = "1.0.47"
+version = "1.0.48"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "6bb623b56e39ab7dcd4b1b98bb6c8f8d907ed255b18de254088016b27a8ee19b"
+checksum = "49922ecae66cc8a249b77e68d1d0623c1b2c514f0060c27cdc68bd62a1219d35"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.29",
+ "syn 2.0.37",
 ]
 
 [[package]]
@@ -1474,9 +1457,9 @@ checksum = "7cda73e2f1397b1262d6dfdcef8aafae14d1de7748d66822d3bfeeb6d03e5e4b"
 
 [[package]]
 name = "toml_edit"
-version = "0.19.14"
+version = "0.19.15"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "f8123f27e969974a3dfba720fdb560be359f57b44302d280ba72e76a74480e8a"
+checksum = "1b5bb770da30e5cbfde35a2d7b9b8a2c4b8ef89548a7a6aeab5c9a576e3e7421"
 dependencies = [
  "indexmap",
  "toml_datetime",
@@ -1485,9 +1468,9 @@ dependencies = [
 
 [[package]]
 name = "unicode-ident"
-version = "1.0.11"
+version = "1.0.12"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "301abaae475aa91687eb82514b328ab47a211a533026cb25fc3e519b86adfc3c"
+checksum = "3354b9ac3fae1ff6755cb6db53683adb661634f67557942dea4facebec0fee4b"
 
 [[package]]
 name = "vec_map"
@@ -1528,7 +1511,7 @@ dependencies = [
  "once_cell",
  "proc-macro2",
  "quote",
- "syn 2.0.29",
+ "syn 2.0.37",
  "wasm-bindgen-shared",
 ]
 
@@ -1550,7 +1533,7 @@ checksum = "54681b18a46765f095758388f2d0cf16eb8d4169b639ab575a8f5693af210c7b"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.29",
+ "syn 2.0.37",
  "wasm-bindgen-backend",
  "wasm-bindgen-shared",
 ]
@@ -1820,9 +1803,9 @@ dependencies = [
 
 [[package]]
 name = "winnow"
-version = "0.5.14"
+version = "0.5.15"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "d09770118a7eb1ccaf4a594a221334119a44a814fcb0d31c5b85e83e97227a97"
+checksum = "7c2e3184b9c4e92ad5167ca73039d0c42476302ab603e2fec4487511f38ccefc"
 dependencies = [
  "memchr",
 ]
@@ -1858,6 +1841,6 @@ dependencies = [
 
 [[package]]
 name = "xml-rs"
-version = "0.8.16"
+version = "0.8.18"
 source = "registry+/~https://github.com/rust-lang/crates.io-index"
-checksum = "47430998a7b5d499ccee752b41567bc3afc57e1327dc855b1a2aa44ce29b5fa1"
+checksum = "bab77e97b50aee93da431f2cee7cd0f43b4d1da3c408042f2d7d164187774f0a"
diff --git a/rayon-core/Cargo.toml b/rayon-core/Cargo.toml
index db7818899..f9eeab65a 100644
--- a/rayon-core/Cargo.toml
+++ b/rayon-core/Cargo.toml
@@ -17,7 +17,6 @@ categories = ["concurrency"]
 
 # Some dependencies may not be their latest version, in order to support older rustc.
 [dependencies]
-num_cpus = "1.2"
 crossbeam-channel = "0.5.0"
 crossbeam-deque = "0.8.1"
 crossbeam-utils = "0.8.0"
diff --git a/rayon-core/src/lib.rs b/rayon-core/src/lib.rs
index 26564f068..a65561d78 100644
--- a/rayon-core/src/lib.rs
+++ b/rayon-core/src/lib.rs
@@ -73,6 +73,7 @@ use std::fmt;
 use std::io;
 use std::marker::PhantomData;
 use std::str::FromStr;
+use std::thread;
 
 #[macro_use]
 mod log;
@@ -458,12 +459,18 @@ impl<S> ThreadPoolBuilder<S> {
         if self.num_threads > 0 {
             self.num_threads
         } else {
+            let default = || {
+                thread::available_parallelism()
+                    .map(|n| n.get())
+                    .unwrap_or(1)
+            };
+
             match env::var("RAYON_NUM_THREADS")
                 .ok()
                 .and_then(|s| usize::from_str(&s).ok())
             {
-                Some(x) if x > 0 => return x,
-                Some(x) if x == 0 => return num_cpus::get(),
+                Some(x @ 1..) => return x,
+                Some(0) => return default(),
                 _ => {}
             }
 
@@ -472,8 +479,8 @@ impl<S> ThreadPoolBuilder<S> {
                 .ok()
                 .and_then(|s| usize::from_str(&s).ok())
             {
-                Some(x) if x > 0 => x,
-                _ => num_cpus::get(),
+                Some(x @ 1..) => x,
+                _ => default(),
             }
         }
     }
@@ -512,9 +519,8 @@ impl<S> ThreadPoolBuilder<S> {
     /// may change in the future, if you wish to rely on a fixed
     /// number of threads, you should use this function to specify
     /// that number. To reproduce the current default behavior, you
-    /// may wish to use the [`num_cpus`
-    /// crate](https://crates.io/crates/num_cpus) to query the number
-    /// of CPUs dynamically.
+    /// may wish to use [`std::thread::available_parallelism`]
+    /// to query the number of CPUs dynamically.
     ///
     /// **Old environment variable:** `RAYON_NUM_THREADS` is a one-to-one
     /// replacement of the now deprecated `RAYON_RS_NUM_CPUS` environment