diff --git a/sys/include/ztimer.h b/sys/include/ztimer.h
index 30b9428532..f87066031b 100644
--- a/sys/include/ztimer.h
+++ b/sys/include/ztimer.h
@@ -430,7 +430,7 @@ bool ztimer_acquire(ztimer_clock_t *clock);
 #else
 static inline bool ztimer_acquire(ztimer_clock_t *clock)
 {
-    (void) clock;
+    (void)clock;
     return false;
 }
 #endif
@@ -450,7 +450,7 @@ bool ztimer_release(ztimer_clock_t *clock);
 #else
 static inline bool ztimer_release(ztimer_clock_t *clock)
 {
-    (void) clock;
+    (void)clock;
     return false;
 }
 #endif
diff --git a/sys/include/ztimer/periodic.h b/sys/include/ztimer/periodic.h
index 9dfd844e3a..c06c648787 100644
--- a/sys/include/ztimer/periodic.h
+++ b/sys/include/ztimer/periodic.h
@@ -89,12 +89,12 @@ typedef bool (*ztimer_periodic_callback_t)(void *);
  * @brief   ztimer periodic structure
  */
 typedef struct {
-    ztimer_t timer;             /**< timer object used for this timer   */
-    ztimer_clock_t *clock;      /**< clock for this timer               */
-    uint32_t interval;          /**< interval of this timer             */
-    ztimer_now_t last;          /**< last trigger time                  */
-    ztimer_periodic_callback_t callback;   /**< called on each trigger             */
-    void *arg;                  /**< argument for callback              */
+    ztimer_t timer;                         /**< timer object used for this timer   */
+    ztimer_clock_t *clock;                  /**< clock for this timer               */
+    uint32_t interval;                      /**< interval of this timer             */
+    ztimer_now_t last;                      /**< last trigger time                  */
+    ztimer_periodic_callback_t callback;    /**< called on each trigger             */
+    void *arg;                              /**< argument for callback              */
 } ztimer_periodic_t;
 
 /**
diff --git a/sys/ztimer/convert.c b/sys/ztimer/convert.c
index 16bb43ea91..2a8b7303c7 100644
--- a/sys/ztimer/convert.c
+++ b/sys/ztimer/convert.c
@@ -56,7 +56,7 @@ void ztimer_convert_init(ztimer_convert_t *ztimer_convert,
     ztimer_convert_t tmp = {
         .lower = lower,
         .lower_entry = {
-            .callback = (void (*)(void *))ztimer_handler,
+            .callback = (void (*)(void *)) ztimer_handler,
             .arg = ztimer_convert,
         },
         .super.max_value = max_value,
diff --git a/sys/ztimer/convert_frac.c b/sys/ztimer/convert_frac.c
index 5a0b6dfa23..97868e9b4b 100644
--- a/sys/ztimer/convert_frac.c
+++ b/sys/ztimer/convert_frac.c
@@ -101,7 +101,7 @@ void ztimer_convert_frac_init(ztimer_convert_frac_t *self,
         .super.super = { .ops = &ztimer_convert_frac_ops, },
         .super.lower = lower,
         .super.lower_entry =
-        { .callback = (void (*)(void *))ztimer_handler, .arg = &self->super, },
+        { .callback = (void (*)(void *)) ztimer_handler, .arg = &self->super, },
     };
 
     ztimer_convert_frac_compute_scale(self, freq_self, freq_lower);