diff --git a/job/queue.cpp b/job/queue.cpp
index 272e93dc..18e21731 100644
--- a/job/queue.cpp
+++ b/job/queue.cpp
@@ -15,8 +15,8 @@ using cruft::job::queue;
 
 
 ///////////////////////////////////////////////////////////////////////////////
-static unsigned
-default_parallelism (void)
+unsigned
+queue::default_parallelism (void) noexcept
 {
     if (auto var = getenv ("JOB_THREADS")) {
         return cruft::from_string<unsigned> (var);
diff --git a/job/queue.hpp b/job/queue.hpp
index e309d2b5..17bd79e1 100644
--- a/job/queue.hpp
+++ b/job/queue.hpp
@@ -42,6 +42,8 @@ namespace cruft::job {
         queue& operator= (const queue&) = delete;
         queue& operator= (queue&&) = delete;
 
+        static unsigned default_parallelism (void) noexcept;
+
         auto parallelism (void) const { return m_threads.size (); }
         auto capacity (void) const { return m_tasks.store.capacity (); }