diff --git a/build.rs b/build.rs
index 5d00811ab..9ec8d4ed2 100644
--- a/build.rs
+++ b/build.rs
@@ -184,9 +184,13 @@ fn have_gettext(target: &Target) -> Result<bool, Box<dyn Error>> {
 /// 0.5 MiB is small enough that we'd have to drastically reduce MAX_STACK_DEPTH to less than 10, so
 /// we instead use a workaround to increase the main thread size.
 fn has_small_stack(_: &Target) -> Result<bool, Box<dyn Error>> {
-    #[cfg(not(target_os = "macos"))]
+    #[cfg(not(any(target_os = "macos", target_os = "netbsd")))]
     return Ok(false);
 
+    // NetBSD 10 also needs this but can't find pthread_get_stacksize_np.
+    #[cfg(target_os = "netbsd")]
+    return Ok(true);
+
     #[cfg(target_os = "macos")]
     {
         use core::ffi;