diff --git a/ci/ci.sh b/ci/ci.sh
index f7c0b739c1..42107adfe5 100755
--- a/ci/ci.sh
+++ b/ci/ci.sh
@@ -168,6 +168,7 @@ case $HOST_TARGET in
     MANY_SEEDS=16 TEST_TARGET=x86_64-unknown-freebsd run_tests
     MANY_SEEDS=16 TEST_TARGET=i686-unknown-freebsd run_tests
     MANY_SEEDS=16 TEST_TARGET=x86_64-unknown-illumos run_tests
+    MANY_SEEDS=16 TEST_TARGET=x86_64-unknown-netbsd run_tests_minimal hello
     ;;
   armv7-unknown-linux-gnueabihf)
     # Host
diff --git a/src/shims/unix/sync.rs b/src/shims/unix/sync.rs
index 4e351c1571..a34314f3fb 100644
--- a/src/shims/unix/sync.rs
+++ b/src/shims/unix/sync.rs
@@ -35,7 +35,13 @@ const PTHREAD_INIT: u8 = 1;
 #[inline]
 fn mutexattr_kind_offset<'tcx>(ecx: &MiriInterpCx<'tcx>) -> InterpResult<'tcx, u64> {
     interp_ok(match &ecx.tcx.sess.target.os {
-        Os::Linux | Os::Illumos | Os::Solaris | Os::MacOs | Os::FreeBsd | Os::Android => 0,
+        Os::Linux
+        | Os::Illumos
+        | Os::Solaris
+        | Os::MacOs
+        | Os::FreeBsd
+        | Os::Android
+        | Os::NetBsd => 0,
         os => throw_unsup_format!("`pthread_mutexattr` is not supported on {os}"),
     })
 }
@@ -135,8 +141,8 @@ impl SyncObj for PthreadMutex {
 fn mutex_init_offset<'tcx>(ecx: &MiriInterpCx<'tcx>) -> InterpResult<'tcx, Size> {
     let offset = match &ecx.tcx.sess.target.os {
         Os::Linux | Os::Illumos | Os::Solaris | Os::FreeBsd | Os::Android => 0,
-        // macOS stores a signature in the first bytes, so we move to offset 4.
-        Os::MacOs => 4,
+        // macOS and NetBSD store a signature in the first bytes, so we move to offset 4.
+        Os::MacOs | Os::NetBsd => 4,
         os => throw_unsup_format!("`pthread_mutex` is not supported on {os}"),
     };
     let offset = Size::from_bytes(offset);
@@ -163,7 +169,7 @@ fn mutex_init_offset<'tcx>(ecx: &MiriInterpCx<'tcx>) -> InterpResult<'tcx, Size>
                 check_static_initializer("PTHREAD_ERRORCHECK_MUTEX_INITIALIZER_NP");
                 check_static_initializer("PTHREAD_ADAPTIVE_MUTEX_INITIALIZER_NP");
             }
-            Os::Illumos | Os::Solaris | Os::MacOs | Os::FreeBsd | Os::Android => {
+            Os::Illumos | Os::Solaris | Os::MacOs | Os::FreeBsd | Os::Android | Os::NetBsd => {
                 // No non-standard initializers.
             }
             os => throw_unsup_format!("`pthread_mutex` is not supported on {os}"),