diff --git a/core/lib/init.c b/core/lib/init.c
index cdf7358a4e..0dbbc6971c 100644
--- a/core/lib/init.c
+++ b/core/lib/init.c
@@ -106,8 +106,11 @@ void kernel_init(void)
                       main_trampoline, NULL, "main");
     }
     else {
+        /* RIOT without threads */
         irq_enable();
         main_trampoline(NULL);
+        while (1) {}
+        return;
     }
 
     cpu_switch_context_exit();
diff --git a/cpu/avr8_common/thread_arch.c b/cpu/avr8_common/thread_arch.c
index 1806db364b..f6529c9fb4 100644
--- a/cpu/avr8_common/thread_arch.c
+++ b/cpu/avr8_common/thread_arch.c
@@ -260,6 +260,10 @@ void NORETURN avr8_enter_thread_mode(void)
 
 void thread_yield_higher(void)
 {
+    if (!IS_USED(MODULE_CORE_THREAD)) {
+        return;
+    }
+
     if (irq_is_in() == 0) {
         avr8_context_save();
         sched_run();
@@ -278,7 +282,8 @@ void avr8_exit_isr(void)
     __asm__ volatile ("" : : : "memory");
 
     /* schedule should switch context when returning from a non nested interrupt */
-    if (sched_context_switch_request && avr8_state_irq_count == 0) {
+    if (sched_context_switch_request && avr8_state_irq_count == 0 &&
+        IS_USED(MODULE_CORE_THREAD)) {
         avr8_context_save();
         sched_run();
         avr8_context_restore();
diff --git a/cpu/native/native_cpu.c b/cpu/native/native_cpu.c
index 5e9e96875a..13fff4e2c4 100644
--- a/cpu/native/native_cpu.c
+++ b/cpu/native/native_cpu.c
@@ -156,7 +156,8 @@ void isr_cpu_switch_context_exit(void)
     ucontext_t *ctx;
 
     DEBUG("isr_cpu_switch_context_exit\n");
-    if ((sched_context_switch_request == 1) || (thread_get_active() == NULL)) {
+    if (((sched_context_switch_request == 1) || (thread_get_active() == NULL))
+        && IS_USED(MODULE_CORE_THREAD)) {
         sched_run();
     }
 
@@ -210,7 +211,11 @@ void isr_thread_yield(void)
         native_irq_handler();
     }
 
+    if (!IS_USED(MODULE_CORE_THREAD)) {
+        return;
+    }
     sched_run();
+
     /* Use intermediate cast to uintptr_t to silence -Wcast-align.
      * stacks are manually word aligned in thread_static_init() */
     ucontext_t *ctx = (ucontext_t *)(uintptr_t)(thread_get_active()->sp);
diff --git a/makefiles/features_modules.inc.mk b/makefiles/features_modules.inc.mk
index c9b958c3af..d24a61dba4 100644
--- a/makefiles/features_modules.inc.mk
+++ b/makefiles/features_modules.inc.mk
@@ -84,7 +84,9 @@ USEMODULE += $(filter cortexm_svc, $(FEATURES_USED))
 
 # select core_idle_thread if the feature no_idle_thread is *not* used
 ifeq (, $(filter no_idle_thread, $(FEATURES_USED)))
-  USEMODULE += core_idle_thread
+  ifneq (,$(filter core_thread, $(USEMODULE)))
+    USEMODULE += core_idle_thread
+  endif
 endif
 
 # use mpu_stack_guard if the feature is used