diff --git a/.ai/instructions.md b/.ai/instructions.md
index 8daee704de..5f314a0dc9 100644
--- a/.ai/instructions.md
+++ b/.ai/instructions.md
@@ -221,6 +221,104 @@ This document provides essential context for AI models interacting with this pro
     *   **Component Development:** Keep dependencies minimal, provide clear error messages, and write comprehensive docstrings and tests.
     *   **Code Generation:** Generate minimal and efficient C++ code. Validate all user inputs thoroughly. Support multiple platform variations.
     *   **Configuration Design:** Aim for simplicity with sensible defaults, while allowing for advanced customization.
+    *   **Embedded Systems Optimization:** ESPHome targets resource-constrained microcontrollers. Be mindful of flash size and RAM usage.
+
+        **STL Container Guidelines:**
+
+        ESPHome runs on embedded systems with limited resources. Choose containers carefully:
+
+        1. **Compile-time-known sizes:** Use `std::array` instead of `std::vector` when size is known at compile time.
+           ```cpp
+           // Bad - generates STL realloc code
+           std::vector<int> values;
+
+           // Good - no dynamic allocation
+           std::array<int, MAX_VALUES> values;
+           ```
+           Use `cg.add_define("MAX_VALUES", count)` to set the size from Python configuration.
+
+           **For byte buffers:** Avoid `std::vector<uint8_t>` unless the buffer needs to grow. Use `std::unique_ptr<uint8_t[]>` instead.
+
+           > **Note:** `std::unique_ptr<uint8_t[]>` does **not** provide bounds checking or iterator support like `std::vector<uint8_t>`. Use it only when you do not need these features and want minimal overhead.
+
+           ```cpp
+           // Bad - STL overhead for simple byte buffer
+           std::vector<uint8_t> buffer;
+           buffer.resize(256);
+
+           // Good - minimal overhead, single allocation
+           std::unique_ptr<uint8_t[]> buffer = std::make_unique<uint8_t[]>(256);
+           // Or if size is constant:
+           std::array<uint8_t, 256> buffer;
+           ```
+
+        2. **Compile-time-known fixed sizes with vector-like API:** Use `StaticVector` from `esphome/core/helpers.h` for fixed-size stack allocation with `push_back()` interface.
+           ```cpp
+           // Bad - generates STL realloc code (_M_realloc_insert)
+           std::vector<ServiceRecord> services;
+           services.reserve(5);  // Still includes reallocation machinery
+
+           // Good - compile-time fixed size, stack allocated, no reallocation machinery
+           StaticVector<ServiceRecord, MAX_SERVICES> services;  // Allocates all MAX_SERVICES on stack
+           services.push_back(record1);  // Tracks count but all slots allocated
+           ```
+           Use `cg.add_define("MAX_SERVICES", count)` to set the size from Python configuration.
+           Like `std::array` but with vector-like API (`push_back()`, `size()`) and no STL reallocation code.
+
+        3. **Runtime-known sizes:** Use `FixedVector` from `esphome/core/helpers.h` when the size is only known at runtime initialization.
+           ```cpp
+           // Bad - generates STL realloc code (_M_realloc_insert)
+           std::vector<TxtRecord> txt_records;
+           txt_records.reserve(5);  // Still includes reallocation machinery
+
+           // Good - runtime size, single allocation, no reallocation machinery
+           FixedVector<TxtRecord> txt_records;
+           txt_records.init(record_count);  // Initialize with exact size at runtime
+           ```
+           **Benefits:**
+           - Eliminates `_M_realloc_insert`, `_M_default_append` template instantiations (saves 200-500 bytes per instance)
+           - Single allocation, no upper bound needed
+           - No reallocation overhead
+           - Compatible with protobuf code generation when using `[(fixed_vector) = true]` option
+
+        4. **Small datasets (1-16 elements):** Use `std::vector` or `std::array` with simple structs instead of `std::map`/`std::set`/`std::unordered_map`.
+           ```cpp
+           // Bad - 2KB+ overhead for red-black tree/hash table
+           std::map<std::string, int> small_lookup;
+           std::unordered_map<int, std::string> tiny_map;
+
+           // Good - simple struct with linear search (std::vector is fine)
+           struct LookupEntry {
+             const char *key;
+             int value;
+           };
+           std::vector<LookupEntry> small_lookup = {
+             {"key1", 10},
+             {"key2", 20},
+             {"key3", 30},
+           };
+           // Or std::array if size is compile-time constant:
+           // std::array<LookupEntry, 3> small_lookup = {{ ... }};
+           ```
+           Linear search on small datasets (1-16 elements) is often faster than hashing/tree overhead, but this depends on lookup frequency and access patterns. For frequent lookups in hot code paths, the O(1) vs O(n) complexity difference may still matter even for small datasets. `std::vector` with simple structs is usually fine—it's the heavy containers (`map`, `set`, `unordered_map`) that should be avoided for small datasets unless profiling shows otherwise.
+
+        5. **Detection:** Look for these patterns in compiler output:
+           - Large code sections with STL symbols (vector, map, set)
+           - `alloc`, `realloc`, `dealloc` in symbol names
+           - `_M_realloc_insert`, `_M_default_append` (vector reallocation)
+           - Red-black tree code (`rb_tree`, `_Rb_tree`)
+           - Hash table infrastructure (`unordered_map`, `hash`)
+
+        **When to optimize:**
+        - Core components (API, network, logger)
+        - Widely-used components (mdns, wifi, ble)
+        - Components causing flash size complaints
+
+        **When not to optimize:**
+        - Single-use niche components
+        - Code where readability matters more than bytes
+        - Already using appropriate containers
+
     *   **State Management:** Use `CORE.data` for component state that needs to persist during configuration generation. Avoid module-level mutable globals.
 
         **Bad Pattern (Module-Level Globals):**
diff --git a/esphome/components/api/api.proto b/esphome/components/api/api.proto
index f7b65c34e3..c7d8fb28f0 100644
--- a/esphome/components/api/api.proto
+++ b/esphome/components/api/api.proto
@@ -776,9 +776,9 @@ message HomeassistantActionRequest {
   option (ifdef) = "USE_API_HOMEASSISTANT_SERVICES";
 
   string service = 1;
-  repeated HomeassistantServiceMap data = 2;
-  repeated HomeassistantServiceMap data_template = 3;
-  repeated HomeassistantServiceMap variables = 4;
+  repeated HomeassistantServiceMap data = 2 [(fixed_vector) = true];
+  repeated HomeassistantServiceMap data_template = 3 [(fixed_vector) = true];
+  repeated HomeassistantServiceMap variables = 4 [(fixed_vector) = true];
   bool is_event = 5;
   uint32 call_id = 6 [(field_ifdef) = "USE_API_HOMEASSISTANT_ACTION_RESPONSES"];
   bool wants_response = 7 [(field_ifdef) = "USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON"];
diff --git a/esphome/components/api/api_pb2.h b/esphome/components/api/api_pb2.h
index 64419eaaa8..20866850a9 100644
--- a/esphome/components/api/api_pb2.h
+++ b/esphome/components/api/api_pb2.h
@@ -1110,9 +1110,9 @@ class HomeassistantActionRequest final : public ProtoMessage {
 #endif
   StringRef service_ref_{};
   void set_service(const StringRef &ref) { this->service_ref_ = ref; }
-  std::vector<HomeassistantServiceMap> data{};
-  std::vector<HomeassistantServiceMap> data_template{};
-  std::vector<HomeassistantServiceMap> variables{};
+  FixedVector<HomeassistantServiceMap> data{};
+  FixedVector<HomeassistantServiceMap> data_template{};
+  FixedVector<HomeassistantServiceMap> variables{};
   bool is_event{false};
 #ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
   uint32_t call_id{0};
diff --git a/esphome/components/api/custom_api_device.h b/esphome/components/api/custom_api_device.h
index 0c6e49d6ca..711eba2444 100644
--- a/esphome/components/api/custom_api_device.h
+++ b/esphome/components/api/custom_api_device.h
@@ -201,9 +201,9 @@ class CustomAPIDevice {
   void call_homeassistant_service(const std::string &service_name, const std::map<std::string, std::string> &data) {
     HomeassistantActionRequest resp;
     resp.set_service(StringRef(service_name));
+    resp.data.init(data.size());
     for (auto &it : data) {
-      resp.data.emplace_back();
-      auto &kv = resp.data.back();
+      auto &kv = resp.data.emplace_back();
       kv.set_key(StringRef(it.first));
       kv.value = it.second;
     }
@@ -244,9 +244,9 @@ class CustomAPIDevice {
     HomeassistantActionRequest resp;
     resp.set_service(StringRef(service_name));
     resp.is_event = true;
+    resp.data.init(data.size());
     for (auto &it : data) {
-      resp.data.emplace_back();
-      auto &kv = resp.data.back();
+      auto &kv = resp.data.emplace_back();
       kv.set_key(StringRef(it.first));
       kv.value = it.second;
     }
diff --git a/esphome/components/api/homeassistant_service.h b/esphome/components/api/homeassistant_service.h
index 730024f7b7..46e89cb39f 100644
--- a/esphome/components/api/homeassistant_service.h
+++ b/esphome/components/api/homeassistant_service.h
@@ -127,24 +127,9 @@ template<typename... Ts> class HomeAssistantServiceCallAction : public Action<Ts
     std::string service_value = this->service_.value(x...);
     resp.set_service(StringRef(service_value));
     resp.is_event = this->flags_.is_event;
-    for (auto &it : this->data_) {
-      resp.data.emplace_back();
-      auto &kv = resp.data.back();
-      kv.set_key(StringRef(it.key));
-      kv.value = it.value.value(x...);
-    }
-    for (auto &it : this->data_template_) {
-      resp.data_template.emplace_back();
-      auto &kv = resp.data_template.back();
-      kv.set_key(StringRef(it.key));
-      kv.value = it.value.value(x...);
-    }
-    for (auto &it : this->variables_) {
-      resp.variables.emplace_back();
-      auto &kv = resp.variables.back();
-      kv.set_key(StringRef(it.key));
-      kv.value = it.value.value(x...);
-    }
+    this->populate_service_map(resp.data, this->data_, x...);
+    this->populate_service_map(resp.data_template, this->data_template_, x...);
+    this->populate_service_map(resp.variables, this->variables_, x...);
 
 #ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
     if (this->flags_.wants_status) {
@@ -189,6 +174,16 @@ template<typename... Ts> class HomeAssistantServiceCallAction : public Action<Ts
   }
 
  protected:
+  template<typename VectorType, typename SourceType>
+  static void populate_service_map(VectorType &dest, SourceType &source, Ts... x) {
+    dest.init(source.size());
+    for (auto &it : source) {
+      auto &kv = dest.emplace_back();
+      kv.set_key(StringRef(it.key));
+      kv.value = it.value.value(x...);
+    }
+  }
+
   APIServer *parent_;
   TemplatableStringValue<Ts...> service_{};
   std::vector<TemplatableKeyValuePair<Ts...>> data_;
diff --git a/esphome/components/homeassistant/number/homeassistant_number.cpp b/esphome/components/homeassistant/number/homeassistant_number.cpp
index c9fb006568..9963f3431d 100644
--- a/esphome/components/homeassistant/number/homeassistant_number.cpp
+++ b/esphome/components/homeassistant/number/homeassistant_number.cpp
@@ -90,13 +90,12 @@ void HomeassistantNumber::control(float value) {
   api::HomeassistantActionRequest resp;
   resp.set_service(SERVICE_NAME);
 
-  resp.data.emplace_back();
-  auto &entity_id = resp.data.back();
+  resp.data.init(2);
+  auto &entity_id = resp.data.emplace_back();
   entity_id.set_key(ENTITY_ID_KEY);
   entity_id.value = this->entity_id_;
 
-  resp.data.emplace_back();
-  auto &entity_value = resp.data.back();
+  auto &entity_value = resp.data.emplace_back();
   entity_value.set_key(VALUE_KEY);
   entity_value.value = to_string(value);
 
diff --git a/esphome/components/homeassistant/switch/homeassistant_switch.cpp b/esphome/components/homeassistant/switch/homeassistant_switch.cpp
index 8feec26fe6..27d3705fc2 100644
--- a/esphome/components/homeassistant/switch/homeassistant_switch.cpp
+++ b/esphome/components/homeassistant/switch/homeassistant_switch.cpp
@@ -51,8 +51,8 @@ void HomeassistantSwitch::write_state(bool state) {
     resp.set_service(SERVICE_OFF);
   }
 
-  resp.data.emplace_back();
-  auto &entity_id_kv = resp.data.back();
+  resp.data.init(1);
+  auto &entity_id_kv = resp.data.emplace_back();
   entity_id_kv.set_key(ENTITY_ID_KEY);
   entity_id_kv.value = this->entity_id_;
 
diff --git a/esphome/components/improv_serial/improv_serial_component.cpp b/esphome/components/improv_serial/improv_serial_component.cpp
index 528a155a7f..28245dcfdf 100644
--- a/esphome/components/improv_serial/improv_serial_component.cpp
+++ b/esphome/components/improv_serial/improv_serial_component.cpp
@@ -218,7 +218,7 @@ bool ImprovSerialComponent::parse_improv_payload_(improv::ImprovCommand &command
     }
     case improv::GET_WIFI_NETWORKS: {
       std::vector<std::string> networks;
-      auto results = wifi::global_wifi_component->get_scan_result();
+      const auto &results = wifi::global_wifi_component->get_scan_result();
       for (auto &scan : results) {
         if (scan.get_is_hidden())
           continue;
diff --git a/esphome/components/light/light_state.cpp b/esphome/components/light/light_state.cpp
index f18d5ba1de..1d139e49e7 100644
--- a/esphome/components/light/light_state.cpp
+++ b/esphome/components/light/light_state.cpp
@@ -177,9 +177,10 @@ void LightState::set_gamma_correct(float gamma_correct) { this->gamma_correct_ =
 void LightState::set_restore_mode(LightRestoreMode restore_mode) { this->restore_mode_ = restore_mode; }
 void LightState::set_initial_state(const LightStateRTCState &initial_state) { this->initial_state_ = initial_state; }
 bool LightState::supports_effects() { return !this->effects_.empty(); }
-const std::vector<LightEffect *> &LightState::get_effects() const { return this->effects_; }
+const FixedVector<LightEffect *> &LightState::get_effects() const { return this->effects_; }
 void LightState::add_effects(const std::vector<LightEffect *> &effects) {
-  this->effects_.reserve(this->effects_.size() + effects.size());
+  // Called once from Python codegen during setup with all effects from YAML config
+  this->effects_.init(effects.size());
   for (auto *effect : effects) {
     this->effects_.push_back(effect);
   }
diff --git a/esphome/components/light/light_state.h b/esphome/components/light/light_state.h
index 1427c02c35..a07aeb6ae5 100644
--- a/esphome/components/light/light_state.h
+++ b/esphome/components/light/light_state.h
@@ -11,8 +11,9 @@
 #include "light_traits.h"
 #include "light_transformer.h"
 
-#include <vector>
+#include "esphome/core/helpers.h"
 #include <strings.h>
+#include <vector>
 
 namespace esphome {
 namespace light {
@@ -159,7 +160,7 @@ class LightState : public EntityBase, public Component {
   bool supports_effects();
 
   /// Get all effects for this light state.
-  const std::vector<LightEffect *> &get_effects() const;
+  const FixedVector<LightEffect *> &get_effects() const;
 
   /// Add effects for this light state.
   void add_effects(const std::vector<LightEffect *> &effects);
@@ -260,7 +261,7 @@ class LightState : public EntityBase, public Component {
   /// The currently active transformer for this light (transition/flash).
   std::unique_ptr<LightTransformer> transformer_{nullptr};
   /// List of effects for this light.
-  std::vector<LightEffect *> effects_;
+  FixedVector<LightEffect *> effects_;
   /// Object used to store the persisted values of the light.
   ESPPreferenceObject rtc_;
   /// Value for storing the index of the currently active effect. 0 if no effect is active
diff --git a/esphome/components/mdns/mdns_component.cpp b/esphome/components/mdns/mdns_component.cpp
index fea3ced99f..d476136554 100644
--- a/esphome/components/mdns/mdns_component.cpp
+++ b/esphome/components/mdns/mdns_component.cpp
@@ -83,7 +83,7 @@ void MDNSComponent::compile_records_(StaticVector<MDNSService, MDNS_SERVICE_COUN
 #endif
 
     auto &txt_records = service.txt_records;
-    txt_records.reserve(txt_count);
+    txt_records.init(txt_count);
 
     if (!friendly_name_empty) {
       txt_records.push_back({MDNS_STR(TXT_FRIENDLY_NAME), MDNS_STR(friendly_name.c_str())});
@@ -171,12 +171,7 @@ void MDNSComponent::compile_records_(StaticVector<MDNSService, MDNS_SERVICE_COUN
   fallback_service.service_type = MDNS_STR(SERVICE_HTTP);
   fallback_service.proto = MDNS_STR(SERVICE_TCP);
   fallback_service.port = USE_WEBSERVER_PORT;
-  fallback_service.txt_records.push_back({MDNS_STR(TXT_VERSION), MDNS_STR(VALUE_VERSION)});
-#endif
-
-#ifdef USE_MDNS_STORE_SERVICES
-  // Copy to member variable if storage is enabled (verbose logging, OpenThread, or extra services)
-  this->services_ = services;
+  fallback_service.txt_records = {{MDNS_STR(TXT_VERSION), MDNS_STR(VALUE_VERSION)}};
 #endif
 }
 
diff --git a/esphome/components/mdns/mdns_component.h b/esphome/components/mdns/mdns_component.h
index 62476e9504..35371fd739 100644
--- a/esphome/components/mdns/mdns_component.h
+++ b/esphome/components/mdns/mdns_component.h
@@ -38,7 +38,7 @@ struct MDNSService {
   // as defined in RFC6763 Section 7, like "_tcp" or "_udp"
   const MDNSString *proto;
   TemplatableValue<uint16_t> port;
-  std::vector<MDNSTXTRecord> txt_records;
+  FixedVector<MDNSTXTRecord> txt_records;
 };
 
 class MDNSComponent : public Component {
diff --git a/esphome/components/mdns/mdns_esp32.cpp b/esphome/components/mdns/mdns_esp32.cpp
index da47be7dbc..f2cb2d3ef5 100644
--- a/esphome/components/mdns/mdns_esp32.cpp
+++ b/esphome/components/mdns/mdns_esp32.cpp
@@ -12,8 +12,13 @@ namespace mdns {
 static const char *const TAG = "mdns";
 
 void MDNSComponent::setup() {
+#ifdef USE_MDNS_STORE_SERVICES
+  this->compile_records_(this->services_);
+  const auto &services = this->services_;
+#else
   StaticVector<MDNSService, MDNS_SERVICE_COUNT> services;
   this->compile_records_(services);
+#endif
 
   esp_err_t err = mdns_init();
   if (err != ESP_OK) {
diff --git a/esphome/components/mdns/mdns_esp8266.cpp b/esphome/components/mdns/mdns_esp8266.cpp
index 06503742db..25a3defa7b 100644
--- a/esphome/components/mdns/mdns_esp8266.cpp
+++ b/esphome/components/mdns/mdns_esp8266.cpp
@@ -12,8 +12,13 @@ namespace esphome {
 namespace mdns {
 
 void MDNSComponent::setup() {
+#ifdef USE_MDNS_STORE_SERVICES
+  this->compile_records_(this->services_);
+  const auto &services = this->services_;
+#else
   StaticVector<MDNSService, MDNS_SERVICE_COUNT> services;
   this->compile_records_(services);
+#endif
 
   MDNS.begin(this->hostname_.c_str());
 
diff --git a/esphome/components/mdns/mdns_libretiny.cpp b/esphome/components/mdns/mdns_libretiny.cpp
index a959482ff6..a3e317a2bf 100644
--- a/esphome/components/mdns/mdns_libretiny.cpp
+++ b/esphome/components/mdns/mdns_libretiny.cpp
@@ -12,8 +12,13 @@ namespace esphome {
 namespace mdns {
 
 void MDNSComponent::setup() {
+#ifdef USE_MDNS_STORE_SERVICES
+  this->compile_records_(this->services_);
+  const auto &services = this->services_;
+#else
   StaticVector<MDNSService, MDNS_SERVICE_COUNT> services;
   this->compile_records_(services);
+#endif
 
   MDNS.begin(this->hostname_.c_str());
 
diff --git a/esphome/components/mdns/mdns_rp2040.cpp b/esphome/components/mdns/mdns_rp2040.cpp
index 9dfb05bda9..791fa3934d 100644
--- a/esphome/components/mdns/mdns_rp2040.cpp
+++ b/esphome/components/mdns/mdns_rp2040.cpp
@@ -12,8 +12,13 @@ namespace esphome {
 namespace mdns {
 
 void MDNSComponent::setup() {
+#ifdef USE_MDNS_STORE_SERVICES
+  this->compile_records_(this->services_);
+  const auto &services = this->services_;
+#else
   StaticVector<MDNSService, MDNS_SERVICE_COUNT> services;
   this->compile_records_(services);
+#endif
 
   MDNS.begin(this->hostname_.c_str());
 
diff --git a/esphome/components/mipi_dsi/models/waveshare.py b/esphome/components/mipi_dsi/models/waveshare.py
index 7cfd6f1645..c3d080f8b2 100644
--- a/esphome/components/mipi_dsi/models/waveshare.py
+++ b/esphome/components/mipi_dsi/models/waveshare.py
@@ -56,50 +56,41 @@ DriverChip(
     "WAVESHARE-P4-86-PANEL",
     height=720,
     width=720,
-    hsync_back_porch=80,
+    hsync_back_porch=50,
     hsync_pulse_width=20,
-    hsync_front_porch=80,
-    vsync_back_porch=12,
+    hsync_front_porch=50,
+    vsync_back_porch=20,
     vsync_pulse_width=4,
-    vsync_front_porch=30,
-    pclk_frequency="46MHz",
-    lane_bit_rate="1Gbps",
+    vsync_front_porch=20,
+    pclk_frequency="38MHz",
+    lane_bit_rate="480Mbps",
     swap_xy=cv.UNDEFINED,
     color_order="RGB",
     reset_pin=27,
     initsequence=[
         (0xB9, 0xF1, 0x12, 0x83),
-        (
-            0xBA, 0x31, 0x81, 0x05, 0xF9, 0x0E, 0x0E, 0x20, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x44, 0x25, 0x00,
-            0x90, 0x0A, 0x00, 0x00, 0x01, 0x4F, 0x01, 0x00, 0x00, 0x37,
-        ),
-        (0xB8, 0x25, 0x22, 0xF0, 0x63),
-        (0xBF, 0x02, 0x11, 0x00),
+        (0xB1, 0x00, 0x00, 0x00, 0xDA, 0x80),
+        (0xB2, 0x3C, 0x12, 0x30),
         (0xB3, 0x10, 0x10, 0x28, 0x28, 0x03, 0xFF, 0x00, 0x00, 0x00, 0x00),
-        (0xC0, 0x73, 0x73, 0x50, 0x50, 0x00, 0x00, 0x12, 0x70, 0x00),
-        (0xBC, 0x46), (0xCC, 0x0B), (0xB4, 0x80), (0xB2, 0x3C, 0x12, 0x30),
-        (0xE3, 0x07, 0x07, 0x0B, 0x0B, 0x03, 0x0B, 0x00, 0x00, 0x00, 0x00, 0xFF, 0x00, 0xC0, 0x10,),
-        (0xC1, 0x36, 0x00, 0x32, 0x32, 0x77, 0xF1, 0xCC, 0xCC, 0x77, 0x77, 0x33, 0x33),
+        (0xB4, 0x80),
         (0xB5, 0x0A, 0x0A),
-        (0xB6, 0xB2, 0xB2),
-        (
-            0xE9, 0xC8, 0x10, 0x0A, 0x10, 0x0F, 0xA1, 0x80, 0x12, 0x31, 0x23, 0x47, 0x86, 0xA1, 0x80,
-            0x47, 0x08, 0x00, 0x00, 0x0D, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0D, 0x00, 0x00, 0x00, 0x48,
-            0x02, 0x8B, 0xAF, 0x46, 0x02, 0x88, 0x88, 0x88, 0x88, 0x88, 0x48, 0x13, 0x8B, 0xAF, 0x57,
-            0x13, 0x88, 0x88, 0x88, 0x88, 0x88, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-            0x00, 0x00, 0x00, 0x00,
-        ),
-        (
-            0xEA, 0x96, 0x12, 0x01, 0x01, 0x01, 0x78, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x4F, 0x31,
-            0x8B, 0xA8, 0x31, 0x75, 0x88, 0x88, 0x88, 0x88, 0x88, 0x4F, 0x20, 0x8B, 0xA8, 0x20, 0x64,
-            0x88, 0x88, 0x88, 0x88, 0x88, 0x23, 0x00, 0x00, 0x01, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00,
-            0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x40, 0xA1, 0x80, 0x00, 0x00,
-            0x00, 0x00,
-        ),
-        (
-            0xE0, 0x00, 0x0A, 0x0F, 0x29, 0x3B, 0x3F, 0x42, 0x39, 0x06, 0x0D, 0x10, 0x13, 0x15, 0x14,
-            0x15, 0x10, 0x17, 0x00, 0x0A, 0x0F, 0x29, 0x3B, 0x3F, 0x42, 0x39, 0x06, 0x0D, 0x10, 0x13,
-            0x15, 0x14, 0x15, 0x10, 0x17,
-        ),
+        (0xB6, 0x97, 0x97),
+        (0xB8, 0x26, 0x22, 0xF0, 0x13),
+        (0xBA, 0x31, 0x81, 0x0F, 0xF9, 0x0E, 0x06, 0x20, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x44, 0x25, 0x00, 0x90, 0x0A, 0x00, 0x00, 0x01, 0x4F, 0x01, 0x00, 0x00, 0x37),
+        (0xBC, 0x47),
+        (0xBF, 0x02, 0x11, 0x00),
+        (0xC0, 0x73, 0x73, 0x50, 0x50, 0x00, 0x00, 0x12, 0x70, 0x00),
+        (0xC1, 0x25, 0x00, 0x32, 0x32, 0x77, 0xE4, 0xFF, 0xFF, 0xCC, 0xCC, 0x77, 0x77),
+        (0xC6, 0x82, 0x00, 0xBF, 0xFF, 0x00, 0xFF),
+        (0xC7, 0xB8, 0x00, 0x0A, 0x10, 0x01, 0x09),
+        (0xC8, 0x10, 0x40, 0x1E, 0x02),
+        (0xCC, 0x0B),
+        (0xE0, 0x00, 0x0B, 0x10, 0x2C, 0x3D, 0x3F, 0x42, 0x3A, 0x07, 0x0D, 0x0F, 0x13, 0x15, 0x13, 0x14, 0x0F, 0x16, 0x00, 0x0B, 0x10, 0x2C, 0x3D, 0x3F, 0x42, 0x3A, 0x07, 0x0D, 0x0F, 0x13, 0x15, 0x13, 0x14, 0x0F, 0x16),
+        (0xE3, 0x07, 0x07, 0x0B, 0x0B, 0x0B, 0x0B, 0x00, 0x00, 0x00, 0x00, 0xFF, 0x00, 0xC0, 0x10),
+        (0xE9, 0xC8, 0x10, 0x0A, 0x00, 0x00, 0x80, 0x81, 0x12, 0x31, 0x23, 0x4F, 0x86, 0xA0, 0x00, 0x47, 0x08, 0x00, 0x00, 0x0C, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0C, 0x00, 0x00, 0x00, 0x98, 0x02, 0x8B, 0xAF, 0x46, 0x02, 0x88, 0x88, 0x88, 0x88, 0x88, 0x98, 0x13, 0x8B, 0xAF, 0x57, 0x13, 0x88, 0x88, 0x88, 0x88, 0x88, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00),
+        (0xEA, 0x97, 0x0C, 0x09, 0x09, 0x09, 0x78, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x9F, 0x31, 0x8B, 0xA8, 0x31, 0x75, 0x88, 0x88, 0x88, 0x88, 0x88, 0x9F, 0x20, 0x8B, 0xA8, 0x20, 0x64, 0x88, 0x88, 0x88, 0x88, 0x88, 0x23, 0x00, 0x00, 0x02, 0x71, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x40, 0x80, 0x81, 0x00, 0x00, 0x00, 0x00),
+        (0xEF, 0xFF, 0xFF, 0x01),
+        (0x11, 0x00),
+        (0x29, 0x00),
     ],
 )
diff --git a/esphome/components/web_server_idf/web_server_idf.cpp b/esphome/components/web_server_idf/web_server_idf.cpp
index d90efd18bc..c3ba7ddc2b 100644
--- a/esphome/components/web_server_idf/web_server_idf.cpp
+++ b/esphome/components/web_server_idf/web_server_idf.cpp
@@ -380,24 +380,25 @@ void AsyncEventSource::handleRequest(AsyncWebServerRequest *request) {
   if (this->on_connect_) {
     this->on_connect_(rsp);
   }
-  this->sessions_.insert(rsp);
+  this->sessions_.push_back(rsp);
 }
 
 void AsyncEventSource::loop() {
   // Clean up dead sessions safely
   // This follows the ESP-IDF pattern where free_ctx marks resources as dead
   // and the main loop handles the actual cleanup to avoid race conditions
-  auto it = this->sessions_.begin();
-  while (it != this->sessions_.end()) {
-    auto *ses = *it;
+  for (size_t i = 0; i < this->sessions_.size();) {
+    auto *ses = this->sessions_[i];
     // If the session has a dead socket (marked by destroy callback)
     if (ses->fd_.load() == 0) {
       ESP_LOGD(TAG, "Removing dead event source session");
-      it = this->sessions_.erase(it);
       delete ses;  // NOLINT(cppcoreguidelines-owning-memory)
+      // Remove by swapping with last element (O(1) removal, order doesn't matter for sessions)
+      this->sessions_[i] = this->sessions_.back();
+      this->sessions_.pop_back();
     } else {
       ses->loop();
-      ++it;
+      ++i;
     }
   }
 }
diff --git a/esphome/components/web_server_idf/web_server_idf.h b/esphome/components/web_server_idf/web_server_idf.h
index bf93dcbd34..5ec6fec009 100644
--- a/esphome/components/web_server_idf/web_server_idf.h
+++ b/esphome/components/web_server_idf/web_server_idf.h
@@ -8,7 +8,6 @@
 #include <functional>
 #include <list>
 #include <map>
-#include <set>
 #include <string>
 #include <utility>
 #include <vector>
@@ -315,7 +314,10 @@ class AsyncEventSource : public AsyncWebHandler {
 
  protected:
   std::string url_;
-  std::set<AsyncEventSourceResponse *> sessions_;
+  // Use vector instead of set: SSE sessions are typically 1-5 connections (browsers, dashboards).
+  // Linear search is faster than red-black tree overhead for this small dataset.
+  // Only operations needed: add session, remove session, iterate sessions - no need for sorted order.
+  std::vector<AsyncEventSourceResponse *> sessions_;
   connect_handler_t on_connect_{};
   esphome::web_server::WebServer *web_server_;
 };
diff --git a/esphome/components/wifi/__init__.py b/esphome/components/wifi/__init__.py
index a784123006..ad5698519b 100644
--- a/esphome/components/wifi/__init__.py
+++ b/esphome/components/wifi/__init__.py
@@ -447,6 +447,8 @@ async def to_code(config):
             var.get_disconnect_trigger(), [], on_disconnect_config
         )
 
+    CORE.add_job(final_step)
+
 
 @automation.register_condition("wifi.connected", WiFiConnectedCondition, cv.Schema({}))
 async def wifi_connected_to_code(config, condition_id, template_arg, args):
@@ -468,6 +470,28 @@ async def wifi_disable_to_code(config, action_id, template_arg, args):
     return cg.new_Pvariable(action_id, template_arg)
 
 
+KEEP_SCAN_RESULTS_KEY = "wifi_keep_scan_results"
+
+
+def request_wifi_scan_results():
+    """Request that WiFi scan results be kept in memory after connection.
+
+    Components that need access to scan results after WiFi is connected should
+    call this function during their code generation. This prevents the WiFi component from
+    freeing scan result memory after successful connection.
+    """
+    CORE.data[KEEP_SCAN_RESULTS_KEY] = True
+
+
+@coroutine_with_priority(CoroPriority.FINAL)
+async def final_step():
+    """Final code generation step to configure scan result retention."""
+    if CORE.data.get(KEEP_SCAN_RESULTS_KEY, False):
+        cg.add(
+            cg.RawExpression("wifi::global_wifi_component->set_keep_scan_results(true)")
+        )
+
+
 @automation.register_action(
     "wifi.configure",
     WiFiConfigureAction,
diff --git a/esphome/components/wifi/wifi_component.cpp b/esphome/components/wifi/wifi_component.cpp
index aa197b36e5..5aa2a03a14 100644
--- a/esphome/components/wifi/wifi_component.cpp
+++ b/esphome/components/wifi/wifi_component.cpp
@@ -549,7 +549,7 @@ void WiFiComponent::start_scanning() {
 // Using insertion sort instead of std::stable_sort saves flash memory
 // by avoiding template instantiations (std::rotate, std::stable_sort, lambdas)
 // IMPORTANT: This sort is stable (preserves relative order of equal elements)
-static void insertion_sort_scan_results(std::vector<WiFiScanResult> &results) {
+template<typename VectorType> static void insertion_sort_scan_results(VectorType &results) {
   const size_t size = results.size();
   for (size_t i = 1; i < size; i++) {
     // Make a copy to avoid issues with move semantics during comparison
@@ -713,6 +713,12 @@ void WiFiComponent::check_connecting_finished() {
     this->state_ = WIFI_COMPONENT_STATE_STA_CONNECTED;
     this->num_retried_ = 0;
 
+    // Free scan results memory unless a component needs them
+    if (!this->keep_scan_results_) {
+      this->scan_result_.clear();
+      this->scan_result_.shrink_to_fit();
+    }
+
     if (this->fast_connect_) {
       this->save_fast_connect_settings_();
     }
diff --git a/esphome/components/wifi/wifi_component.h b/esphome/components/wifi/wifi_component.h
index 0e0f89d2c1..9d32071b2b 100644
--- a/esphome/components/wifi/wifi_component.h
+++ b/esphome/components/wifi/wifi_component.h
@@ -121,6 +121,14 @@ struct EAPAuth {
 
 using bssid_t = std::array<uint8_t, 6>;
 
+// Use std::vector for RP2040 since scan count is unknown (callback-based)
+// Use FixedVector for other platforms where count is queried first
+#ifdef USE_RP2040
+template<typename T> using wifi_scan_vector_t = std::vector<T>;
+#else
+template<typename T> using wifi_scan_vector_t = FixedVector<T>;
+#endif
+
 class WiFiAP {
  public:
   void set_ssid(const std::string &ssid);
@@ -278,7 +286,7 @@ class WiFiComponent : public Component {
   const std::string &get_use_address() const;
   void set_use_address(const std::string &use_address);
 
-  const std::vector<WiFiScanResult> &get_scan_result() const { return scan_result_; }
+  const wifi_scan_vector_t<WiFiScanResult> &get_scan_result() const { return scan_result_; }
 
   network::IPAddress wifi_soft_ap_ip();
 
@@ -316,6 +324,7 @@ class WiFiComponent : public Component {
   int8_t wifi_rssi();
 
   void set_enable_on_boot(bool enable_on_boot) { this->enable_on_boot_ = enable_on_boot; }
+  void set_keep_scan_results(bool keep_scan_results) { this->keep_scan_results_ = keep_scan_results; }
 
   Trigger<> *get_connect_trigger() const { return this->connect_trigger_; };
   Trigger<> *get_disconnect_trigger() const { return this->disconnect_trigger_; };
@@ -385,7 +394,7 @@ class WiFiComponent : public Component {
   std::string use_address_;
   std::vector<WiFiAP> sta_;
   std::vector<WiFiSTAPriority> sta_priorities_;
-  std::vector<WiFiScanResult> scan_result_;
+  wifi_scan_vector_t<WiFiScanResult> scan_result_;
   WiFiAP selected_ap_;
   WiFiAP ap_;
   optional<float> output_power_;
@@ -424,6 +433,7 @@ class WiFiComponent : public Component {
 #endif
   bool enable_on_boot_;
   bool got_ipv4_address_{false};
+  bool keep_scan_results_{false};
 
   // Pointers at the end (naturally aligned)
   Trigger<> *connect_trigger_{new Trigger<>()};
diff --git a/esphome/components/wifi/wifi_component_esp8266.cpp b/esphome/components/wifi/wifi_component_esp8266.cpp
index 3b3b4b139c..59909b2cb5 100644
--- a/esphome/components/wifi/wifi_component_esp8266.cpp
+++ b/esphome/components/wifi/wifi_component_esp8266.cpp
@@ -696,7 +696,15 @@ void WiFiComponent::wifi_scan_done_callback_(void *arg, STATUS status) {
     this->retry_connect();
     return;
   }
+
+  // Count the number of results first
   auto *head = reinterpret_cast<bss_info *>(arg);
+  size_t count = 0;
+  for (bss_info *it = head; it != nullptr; it = STAILQ_NEXT(it, next)) {
+    count++;
+  }
+
+  this->scan_result_.init(count);
   for (bss_info *it = head; it != nullptr; it = STAILQ_NEXT(it, next)) {
     WiFiScanResult res({it->bssid[0], it->bssid[1], it->bssid[2], it->bssid[3], it->bssid[4], it->bssid[5]},
                        std::string(reinterpret_cast<char *>(it->ssid), it->ssid_len), it->channel, it->rssi,
diff --git a/esphome/components/wifi/wifi_component_esp_idf.cpp b/esphome/components/wifi/wifi_component_esp_idf.cpp
index ccec800205..951f5803a6 100644
--- a/esphome/components/wifi/wifi_component_esp_idf.cpp
+++ b/esphome/components/wifi/wifi_component_esp_idf.cpp
@@ -784,7 +784,7 @@ void WiFiComponent::wifi_process_event_(IDFWiFiEvent *data) {
     }
     records.resize(number);
 
-    scan_result_.reserve(number);
+    scan_result_.init(number);
     for (int i = 0; i < number; i++) {
       auto &record = records[i];
       bssid_t bssid;
diff --git a/esphome/components/wifi/wifi_component_libretiny.cpp b/esphome/components/wifi/wifi_component_libretiny.cpp
index b15f710150..cb179d9022 100644
--- a/esphome/components/wifi/wifi_component_libretiny.cpp
+++ b/esphome/components/wifi/wifi_component_libretiny.cpp
@@ -411,7 +411,7 @@ void WiFiComponent::wifi_scan_done_callback_() {
   if (num < 0)
     return;
 
-  this->scan_result_.reserve(static_cast<unsigned int>(num));
+  this->scan_result_.init(static_cast<unsigned int>(num));
   for (int i = 0; i < num; i++) {
     String ssid = WiFi.SSID(i);
     wifi_auth_mode_t authmode = WiFi.encryptionType(i);
diff --git a/esphome/components/wifi_info/text_sensor.py b/esphome/components/wifi_info/text_sensor.py
index 4ceb73a695..a4da582c55 100644
--- a/esphome/components/wifi_info/text_sensor.py
+++ b/esphome/components/wifi_info/text_sensor.py
@@ -1,5 +1,5 @@
 import esphome.codegen as cg
-from esphome.components import text_sensor
+from esphome.components import text_sensor, wifi
 import esphome.config_validation as cv
 from esphome.const import (
     CONF_BSSID,
@@ -77,7 +77,9 @@ async def to_code(config):
     await setup_conf(config, CONF_SSID)
     await setup_conf(config, CONF_BSSID)
     await setup_conf(config, CONF_MAC_ADDRESS)
-    await setup_conf(config, CONF_SCAN_RESULTS)
+    if CONF_SCAN_RESULTS in config:
+        await setup_conf(config, CONF_SCAN_RESULTS)
+        wifi.request_wifi_scan_results()
     await setup_conf(config, CONF_DNS_ADDRESS)
     if conf := config.get(CONF_IP_ADDRESS):
         wifi_info = await text_sensor.new_text_sensor(config[CONF_IP_ADDRESS])
diff --git a/esphome/core/base_automation.h b/esphome/core/base_automation.h
index ba942e5e43..f1248e0035 100644
--- a/esphome/core/base_automation.h
+++ b/esphome/core/base_automation.h
@@ -7,6 +7,7 @@
 #include "esphome/core/preferences.h"
 #include "esphome/core/scheduler.h"
 #include "esphome/core/application.h"
+#include "esphome/core/helpers.h"
 
 #include <vector>
 
@@ -14,7 +15,7 @@ namespace esphome {
 
 template<typename... Ts> class AndCondition : public Condition<Ts...> {
  public:
-  explicit AndCondition(const std::vector<Condition<Ts...> *> &conditions) : conditions_(conditions) {}
+  explicit AndCondition(std::initializer_list<Condition<Ts...> *> conditions) : conditions_(conditions) {}
   bool check(Ts... x) override {
     for (auto *condition : this->conditions_) {
       if (!condition->check(x...))
@@ -25,12 +26,12 @@ template<typename... Ts> class AndCondition : public Condition<Ts...> {
   }
 
  protected:
-  std::vector<Condition<Ts...> *> conditions_;
+  FixedVector<Condition<Ts...> *> conditions_;
 };
 
 template<typename... Ts> class OrCondition : public Condition<Ts...> {
  public:
-  explicit OrCondition(const std::vector<Condition<Ts...> *> &conditions) : conditions_(conditions) {}
+  explicit OrCondition(std::initializer_list<Condition<Ts...> *> conditions) : conditions_(conditions) {}
   bool check(Ts... x) override {
     for (auto *condition : this->conditions_) {
       if (condition->check(x...))
@@ -41,7 +42,7 @@ template<typename... Ts> class OrCondition : public Condition<Ts...> {
   }
 
  protected:
-  std::vector<Condition<Ts...> *> conditions_;
+  FixedVector<Condition<Ts...> *> conditions_;
 };
 
 template<typename... Ts> class NotCondition : public Condition<Ts...> {
@@ -55,7 +56,7 @@ template<typename... Ts> class NotCondition : public Condition<Ts...> {
 
 template<typename... Ts> class XorCondition : public Condition<Ts...> {
  public:
-  explicit XorCondition(const std::vector<Condition<Ts...> *> &conditions) : conditions_(conditions) {}
+  explicit XorCondition(std::initializer_list<Condition<Ts...> *> conditions) : conditions_(conditions) {}
   bool check(Ts... x) override {
     size_t result = 0;
     for (auto *condition : this->conditions_) {
@@ -66,7 +67,7 @@ template<typename... Ts> class XorCondition : public Condition<Ts...> {
   }
 
  protected:
-  std::vector<Condition<Ts...> *> conditions_;
+  FixedVector<Condition<Ts...> *> conditions_;
 };
 
 template<typename... Ts> class LambdaCondition : public Condition<Ts...> {
diff --git a/esphome/core/helpers.h b/esphome/core/helpers.h
index e352c9c415..326718e974 100644
--- a/esphome/core/helpers.h
+++ b/esphome/core/helpers.h
@@ -197,6 +197,18 @@ template<typename T> class FixedVector {
  public:
   FixedVector() = default;
 
+  /// Constructor from initializer list - allocates exact size needed
+  /// This enables brace initialization: FixedVector<int> v = {1, 2, 3};
+  FixedVector(std::initializer_list<T> init_list) {
+    init(init_list.size());
+    size_t idx = 0;
+    for (const auto &item : init_list) {
+      new (data_ + idx) T(item);
+      ++idx;
+    }
+    size_ = init_list.size();
+  }
+
   ~FixedVector() { cleanup_(); }
 
   // Disable copy operations (avoid accidental expensive copies)
diff --git a/netlify.toml b/netlify.toml
index 7783414a91..5f177e6b3a 100644
--- a/netlify.toml
+++ b/netlify.toml
@@ -1,3 +1,4 @@
 [build]
   command = "script/build-api-docs"
   publish = "api-docs"
+  environment = { PYTHON_VERSION = "3.13" }
diff --git a/requirements.txt b/requirements.txt
index 4425a4644e..1abfed0324 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -12,13 +12,13 @@ platformio==6.1.18  # When updating platformio, also update /docker/Dockerfile
 esptool==5.1.0
 click==8.1.7
 esphome-dashboard==20251013.0
-aioesphomeapi==41.16.1
+aioesphomeapi==41.17.0
 zeroconf==0.148.0
 puremagic==1.30
 ruamel.yaml==0.18.15 # dashboard_import
-ruamel.yaml.clib==0.2.12 # dashboard_import
+ruamel.yaml.clib==0.2.14 # dashboard_import
 esphome-glyphsets==0.2.0
-pillow==10.4.0
+pillow==11.3.0
 cairosvg==2.8.2
 freetype-py==2.5.1
 jinja2==3.1.6
diff --git a/tests/components/pzemac/test.esp32-idf.yaml b/tests/components/pzemac/test.esp32-idf.yaml
index 37d98696cc..b631e16677 100644
--- a/tests/components/pzemac/test.esp32-idf.yaml
+++ b/tests/components/pzemac/test.esp32-idf.yaml
@@ -1,6 +1,7 @@
 substitutions:
   tx_pin: GPIO4
   rx_pin: GPIO5
+  flow_control_pin: GPIO13
 
 packages:
   modbus: !include ../../test_build_components/common/modbus/esp32-idf.yaml
diff --git a/tests/components/pzemdc/test.esp32-idf.yaml b/tests/components/pzemdc/test.esp32-idf.yaml
index 37d98696cc..b631e16677 100644
--- a/tests/components/pzemdc/test.esp32-idf.yaml
+++ b/tests/components/pzemdc/test.esp32-idf.yaml
@@ -1,6 +1,7 @@
 substitutions:
   tx_pin: GPIO4
   rx_pin: GPIO5
+  flow_control_pin: GPIO13
 
 packages:
   modbus: !include ../../test_build_components/common/modbus/esp32-idf.yaml
diff --git a/tests/components/sdm_meter/test.esp32-idf.yaml b/tests/components/sdm_meter/test.esp32-idf.yaml
index 37d98696cc..b631e16677 100644
--- a/tests/components/sdm_meter/test.esp32-idf.yaml
+++ b/tests/components/sdm_meter/test.esp32-idf.yaml
@@ -1,6 +1,7 @@
 substitutions:
   tx_pin: GPIO4
   rx_pin: GPIO5
+  flow_control_pin: GPIO13
 
 packages:
   modbus: !include ../../test_build_components/common/modbus/esp32-idf.yaml