diff --git a/basis/system-info/linux/linux.factor b/basis/system-info/linux/linux.factor
index 09f2a91bc8..ab16ddc366 100644
--- a/basis/system-info/linux/linux.factor
+++ b/basis/system-info/linux/linux.factor
@@ -23,6 +23,6 @@ FUNCTION-ALIAS: (uname)
 M: linux os-version release ;
 M: linux cpus parse-proc-cpuinfo sort-cpus cpu-counts 2drop ;
 : cores ( -- n ) parse-proc-cpuinfo sort-cpus cpu-counts drop nip ;
-: hyperthreads ( -- n ) parse-proc-cpuinfo sort-cpus cpu-counts 2nip ;
+M: linux hyperthreads ( -- n ) parse-proc-cpuinfo sort-cpus cpu-counts 2nip ;
 M: linux cpu-mhz parse-proc-cpuinfo first cpu-mhz>> 1,000,000 * ;
 M: linux physical-mem parse-proc-meminfo mem-total>> ;
diff --git a/basis/system-info/macosx/macosx.factor b/basis/system-info/macosx/macosx.factor
index 16951b4471..1a99646a83 100644
--- a/basis/system-info/macosx/macosx.factor
+++ b/basis/system-info/macosx/macosx.factor
@@ -74,6 +74,7 @@ FUNCTION: int sysctl ( int* name, uint namelen, void* oldp, size_t* oldlenp, voi
 : machine ( -- str ) { 6 1 } sysctl-query-string ;
 : model ( -- str ) { 6 2 } sysctl-query-string ;
 M: macosx cpus ( -- n ) { 6 3 } sysctl-query-uint ;
+M: macosx hyperthreads ( -- n ) { 6 3 } sysctl-query-uint ;
 : byte-order ( -- n ) { 6 4 } sysctl-query-uint ;
 
 ! Only an int, not large enough. Deprecated.
diff --git a/basis/system-info/system-info.factor b/basis/system-info/system-info.factor
index 156d20ed8e..63b81f05ff 100644
--- a/basis/system-info/system-info.factor
+++ b/basis/system-info/system-info.factor
@@ -6,6 +6,7 @@ IN: system-info
 
 HOOK: os-version os ( -- version )
 HOOK: cpus os ( -- n )
+HOOK: hyperthreads os ( -- n )
 HOOK: cpu-mhz os ( -- n )
 HOOK: memory-load os ( -- n )
 HOOK: physical-mem os ( -- n )