diff --git a/src/base/array.h b/src/base/array.h
index 4da7e70..d6226cf 100644
--- a/src/base/array.h
+++ b/src/base/array.h
@@ -5,6 +5,12 @@
 
 #include "base/memory.h"
 
+static constexpr size_t INIT_CAPACITY = 4;
+static inline size_t next_capacity(size_t capacity) {
+  if (capacity) return capacity * 2;
+  return INIT_CAPACITY;
+}
+
 /**
  * @file array.h
  * @brief 动态数组基础操作。
diff --git a/src/base/memory.h b/src/base/memory.h
index 705d1da..39e093f 100644
--- a/src/base/memory.h
+++ b/src/base/memory.h
@@ -5,8 +5,6 @@
 #include <string.h>
 #include <sys/types.h>
 
-#include "base/macros.h"
-
 #define p_alloc_nr(x) (((x) + 16) * 3 / 2)
 #define p_new(type, count) ((type *)xmalloc(sizeof(type) * (count)))
 #define p_clear(p, count) ((void)memset((p), 0, sizeof(*(p)) * (count)))
@@ -65,9 +63,3 @@ static inline void xrealloc(void **ptr, ssize_t newsize) {
  * Unlike strlen(), a_strlen() accepts nullptr and returns 0 in that case.
  */
 static inline ssize_t a_strlen(const char *s) { return s ? strlen(s) : 0; }
-
-static constexpr size_t INIT_CAPACITY = 4;
-static inline size_t next_capacity(size_t capacity) {
-  if (capacity) return capacity * 2;
-  return INIT_CAPACITY;
-}
diff --git a/src/config/runtime_config.c b/src/config/runtime_config.c
index 5bd0d2a..772de6b 100644
--- a/src/config/runtime_config.c
+++ b/src/config/runtime_config.c
@@ -3,6 +3,7 @@
 #include <dlfcn.h>
 #include <zdwm/config.h>
 
+#include "base/array.h"
 #include "base/memory.h"
 #include "config/defaults.h"
 #include "config/loader.h"
@@ -42,31 +43,6 @@ static void config_builder_cleanup(zdwm_config_builder_t *builder) {
   builder->output_count = 0;
 }
 
-static bool config_builder_init(zdwm_config_builder_t *builder,
-                                size_t output_count) {
-  if (!builder || output_count == 0) return false;
-
-  p_clear(builder, 1);
-  builder->output_count = output_count;
-  layout_registry_init(&builder->layouts);
-  return true;
-}
-
-static bool config_builder_ensure_workspace_capacity(
-  zdwm_config_builder_t *builder) {
-  if (!builder) return false;
-  if (builder->workspace_count < builder->workspace_capacity) return true;
-
-  size_t capacity = next_capacity(builder->workspace_capacity);
-  if (!builder->workspaces) {
-    builder->workspaces = p_new(workspace_desc_t, capacity);
-  } else {
-    p_realloc(&builder->workspaces, capacity);
-  }
-  builder->workspace_capacity = capacity;
-  return true;
-}
-
 static layout_id_t runtime_config_register_layout(
   zdwm_config_builder_t *builder, const char *name, const char *symbol,
   const char *description, layout_fn fn) {
@@ -101,18 +77,15 @@ static workspace_id_t runtime_config_define_workspace(
       return ZDWM_WORKSPACE_ID_INVALID;
     }
   }
-  if (!config_builder_ensure_workspace_capacity(builder)) {
-    return ZDWM_WORKSPACE_ID_INVALID;
-  }
 
   workspace_id_t workspace_id = (workspace_id_t)builder->workspace_count;
-  workspace_desc_t *slot = &builder->workspaces[builder->workspace_count];
+  workspace_desc_t *slot = array_push(
+    builder->workspaces, builder->workspace_count, builder->workspace_capacity);
   slot->output_index = output_index;
   slot->name = p_strdup(name);
   slot->layout_ids = p_copy(layout_ids, layout_count);
   slot->layout_count = layout_count;
   slot->initial_layout_id = initial_layout_id;
-  builder->workspace_count++;
   return workspace_id;
 }
 
@@ -138,7 +111,7 @@ static bool runtime_config_build(zdwm_config_setup_fn *setup,
                                  runtime_init_desc_t *out) {
   if (!setup || !out) return false;
   zdwm_config_builder_t builder = {0};
-  if (!config_builder_init(&builder, output_count)) return false;
+  builder.output_count = output_count;
 
   zdwm_api_t api = {
     .abi_version = ZDWM_CONFIG_ABI_VERSION,
diff --git a/src/core/layout.c b/src/core/layout.c
index 0561a47..fe1968d 100644
--- a/src/core/layout.c
+++ b/src/core/layout.c
@@ -4,13 +4,9 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "base/array.h"
 #include "base/memory.h"
-
-void layout_result_init(layout_result_t *result) {
-  result->item_count = 0;
-  result->item_capacity = INIT_CAPACITY;
-  result->items = p_new(layout_item_t, result->item_capacity);
-}
+#include "core/types.h"
 
 void layout_result_cleanup(layout_result_t *result) {
   p_delete(&result->items);
@@ -19,19 +15,9 @@ void layout_result_cleanup(layout_result_t *result) {
 }
 
 void layout_result_push(layout_result_t *result, layout_item_t item) {
-  if (result->item_count == result->item_capacity) {
-    size_t new_capacity = next_capacity(result->item_capacity);
-    p_realloc(&result->items, new_capacity);
-    result->item_capacity = new_capacity;
-  }
-
-  result->items[result->item_count++] = item;
-}
-
-void layout_registry_init(layout_registry_t *registry) {
-  registry->slot_count = 0;
-  registry->slot_capacity = INIT_CAPACITY;
-  registry->slots = p_new(layout_slot_t, registry->slot_capacity);
+  layout_item_t *slot =
+    array_push(result->items, result->item_count, result->item_capacity);
+  *slot = item;
 }
 
 void layout_registry_cleanup(layout_registry_t *registry) {
@@ -77,22 +63,16 @@ layout_id_t layout_register(layout_registry_t *registry, const char *name,
                             layout_fn fn) {
   if (!name || !symbol) return ZDWM_LAYOUT_ID_INVALID;
 
-  if (registry->slot_count == registry->slot_capacity) {
-    size_t new_capacity = next_capacity(registry->slot_capacity);
-    p_realloc(&registry->slots, new_capacity);
-    registry->slot_capacity = new_capacity;
-  }
   layout_id_t id = (layout_id_t)registry->slot_count;
-
-  layout_slot_t *r = &registry->slots[registry->slot_count];
+  layout_slot_t *r =
+    array_push(registry->slots, registry->slot_count, registry->slot_capacity);
   r->id = id;
   r->name = p_strdup(name);
   r->symbol = p_strdup(symbol);
   r->description = p_strdup_nullable(description);
   r->fn = fn;
 
-  registry->slot_count++;
-  return id;
+  return r->id;
 }
 
 layout_fn layout_get(const layout_registry_t *registry, layout_id_t id) {
diff --git a/src/core/layout.h b/src/core/layout.h
index 3ce06c8..78bfb83 100644
--- a/src/core/layout.h
+++ b/src/core/layout.h
@@ -47,24 +47,10 @@ typedef struct layout_registry_t {
   size_t slot_capacity;
 } layout_registry_t;
 
-/*
- * 调用约束：
- * - result 必须是有效的非空指针
- * - 除 init 之外，其余 result 相关接口都要求 result 已初始化
- * - 传入空指针或未初始化对象属于调用方错误
- */
-void layout_result_init(layout_result_t *result);
 void layout_result_cleanup(layout_result_t *result);
 
 void layout_result_push(layout_result_t *result, layout_item_t item);
 
-/*
- * 调用约束：
- * - registry 必须是有效的非空指针
- * - 除 init 之外，其余 registry 相关接口都要求 registry 已初始化
- * - 传入空指针或未初始化对象属于调用方错误
- */
-void layout_registry_init(layout_registry_t *registry);
 void layout_registry_cleanup(layout_registry_t *registry);
 bool layout_registry_move(layout_registry_t *src, layout_registry_t *dest);
 size_t layout_registry_count(const layout_registry_t *registry);
diff --git a/src/core/state.c b/src/core/state.c
index f91ddfb..67e0c8d 100644
--- a/src/core/state.c
+++ b/src/core/state.c
@@ -3,6 +3,7 @@
 #include <stddef.h>
 #include <string.h>
 
+#include "base/array.h"
 #include "base/log.h"
 #include "base/memory.h"
 #include "core/types.h"
@@ -257,19 +258,19 @@ const window_t *state_window_add(state_t *state, const window_info_t *info) {
   window_id_t id = info->id;
   window_t *window = (window_t *)state_window_get(state, id);
   if (!window) {
-    if (state->window_count == state->window_capacity) {
-      size_t capacity = next_capacity(state->window_capacity);
-      p_realloc(&state->windows, capacity);
-      p_realloc(&state->stack_order, capacity);
-      state->window_capacity = capacity;
+    size_t index = state->window_count;
+    size_t old_capacity = state->window_capacity;
+    window =
+      array_push(state->windows, state->window_count, state->window_capacity);
+    if (old_capacity != state->window_capacity) {
+      p_realloc(&state->stack_order, state->window_capacity);
     }
-    window = &state->windows[state->window_count];
+
     p_clear(window, 1);
     window->id = id;
     window->workspace_id = ZDWM_WORKSPACE_ID_INVALID;
 
-    state->stack_order[state->window_count] = id;
-    state->window_count++;
+    state->stack_order[index] = id;
   }
 
   state_window_set_geometry_mode(state, id, info->geometry_mode);
diff --git a/src/rect.c b/src/rect.c
index 9baf8dd..8475ec1 100644
--- a/src/rect.c
+++ b/src/rect.c
@@ -1,6 +1,7 @@
 #include "rect.h"
 
-#include "utils.h"
+#include "base/macros.h"
+#include "base/memory.h"
 
 static inline bool rect_valid(rect_t rect) {
   return rect.x1 < rect.x2 && rect.y1 < rect.y2;
diff --git a/tests/config/runtime_config_test.c b/tests/config/runtime_config_test.c
index 0cb7807..e94c8a8 100644
--- a/tests/config/runtime_config_test.c
+++ b/tests/config/runtime_config_test.c
@@ -98,7 +98,6 @@ static void test_runtime_config_keeps_module_loaded_after_runtime_init(
   assert(layout != nullptr);
 
   layout_result_t result = {0};
-  layout_result_init(&result);
 
   layout_ctx_t ctx = {
     .workspace_id = 0,
@@ -120,7 +119,8 @@ static void test_runtime_config_keeps_module_loaded_after_runtime_init(
   assert(runtime.config_module_handle == nullptr);
 }
 
-static void test_runtime_config_falls_back_to_defaults_when_implicit_library_is_missing(
+static void
+test_runtime_config_falls_back_to_defaults_when_implicit_library_is_missing(
   void) {
   config_test_clear_env();