diff --git a/src/DebugConfiguration.h b/src/DebugConfiguration.h
index 98bbe0f729..173096b654 100644
--- a/src/DebugConfiguration.h
+++ b/src/DebugConfiguration.h
@@ -53,12 +53,42 @@ extern MemGet memGet;
 #define LOG_TRACE(...) SEGGER_RTT_printf(0, __VA_ARGS__)
 #else
 #if defined(DEBUG_PORT) && !defined(DEBUG_MUTE)
-#define LOG_DEBUG(...) DEBUG_PORT.log(MESHTASTIC_LOG_LEVEL_DEBUG, __VA_ARGS__)
-#define LOG_INFO(...) DEBUG_PORT.log(MESHTASTIC_LOG_LEVEL_INFO, __VA_ARGS__)
-#define LOG_WARN(...) DEBUG_PORT.log(MESHTASTIC_LOG_LEVEL_WARN, __VA_ARGS__)
-#define LOG_ERROR(...) DEBUG_PORT.log(MESHTASTIC_LOG_LEVEL_ERROR, __VA_ARGS__)
-#define LOG_CRIT(...) DEBUG_PORT.log(MESHTASTIC_LOG_LEVEL_CRIT, __VA_ARGS__)
-#define LOG_TRACE(...) DEBUG_PORT.log(MESHTASTIC_LOG_LEVEL_TRACE, __VA_ARGS__)
+#define LOG_DEBUG(...)                                                                                                           \
+    do {                                                                                                                         \
+        if (console) {                                                                                                           \
+            console->log(MESHTASTIC_LOG_LEVEL_DEBUG, __VA_ARGS__);                                                               \
+        }                                                                                                                        \
+    } while (0)
+#define LOG_INFO(...)                                                                                                            \
+    do {                                                                                                                         \
+        if (console) {                                                                                                           \
+            console->log(MESHTASTIC_LOG_LEVEL_INFO, __VA_ARGS__);                                                                \
+        }                                                                                                                        \
+    } while (0)
+#define LOG_WARN(...)                                                                                                            \
+    do {                                                                                                                         \
+        if (console) {                                                                                                           \
+            console->log(MESHTASTIC_LOG_LEVEL_WARN, __VA_ARGS__);                                                                \
+        }                                                                                                                        \
+    } while (0)
+#define LOG_ERROR(...)                                                                                                           \
+    do {                                                                                                                         \
+        if (console) {                                                                                                           \
+            console->log(MESHTASTIC_LOG_LEVEL_ERROR, __VA_ARGS__);                                                               \
+        }                                                                                                                        \
+    } while (0)
+#define LOG_CRIT(...)                                                                                                            \
+    do {                                                                                                                         \
+        if (console) {                                                                                                           \
+            console->log(MESHTASTIC_LOG_LEVEL_CRIT, __VA_ARGS__);                                                                \
+        }                                                                                                                        \
+    } while (0)
+#define LOG_TRACE(...)                                                                                                           \
+    do {                                                                                                                         \
+        if (console) {                                                                                                           \
+            console->log(MESHTASTIC_LOG_LEVEL_TRACE, __VA_ARGS__);                                                               \
+        }                                                                                                                        \
+    } while (0)
 #else
 #define LOG_DEBUG(...)
 #define LOG_INFO(...)
@@ -70,7 +100,12 @@ extern MemGet memGet;
 #endif
 
 #if defined(DEBUG_HEAP)
-#define LOG_HEAP(...) DEBUG_PORT.log(MESHTASTIC_LOG_LEVEL_HEAP, __VA_ARGS__)
+#define LOG_HEAP(...)                                                                                                            \
+    do {                                                                                                                         \
+        if (console) {                                                                                                           \
+            console->log(MESHTASTIC_LOG_LEVEL_HEAP, __VA_ARGS__);                                                                \
+        }                                                                                                                        \
+    } while (0)
 
 // Macro-based heap debugging
 #define DEBUG_HEAP_BEFORE auto heapBefore = memGet.getFreeHeap();
@@ -195,4 +230,4 @@ class Syslog
     bool vlogf(uint16_t pri, const char *appName, const char *fmt, va_list args) __attribute__((format(printf, 3, 0)));
 };
 
-#endif // HAS_NETWORKING
\ No newline at end of file
+#endif // HAS_NETWORKING
diff --git a/src/NodeStatus.h b/src/NodeStatus.h
index 550f6254a6..07d2dd4473 100644
--- a/src/NodeStatus.h
+++ b/src/NodeStatus.h
@@ -65,4 +65,4 @@ class NodeStatus : public Status
 
 } // namespace meshtastic
 
-extern meshtastic::NodeStatus *nodeStatus;
\ No newline at end of file
+extern meshtastic::NodeStatus *nodeStatus;
diff --git a/src/graphics/niche/InkHUD/Applets/Bases/Map/MapApplet.cpp b/src/graphics/niche/InkHUD/Applets/Bases/Map/MapApplet.cpp
index d383a11e45..ab58b55e8d 100644
--- a/src/graphics/niche/InkHUD/Applets/Bases/Map/MapApplet.cpp
+++ b/src/graphics/niche/InkHUD/Applets/Bases/Map/MapApplet.cpp
@@ -555,4 +555,4 @@ void InkHUD::MapApplet::drawCross(int16_t x, int16_t y, uint8_t size)
     drawLine(x0, y1, x1, y0, BLACK);
 }
 
-#endif
\ No newline at end of file
+#endif
diff --git a/src/main.cpp b/src/main.cpp
index c654822927..b7beba70ad 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -295,7 +295,7 @@ void printInfo()
 {
     LOG_INFO("S:B:%d,%s,%s,%s", HW_VENDOR, optstr(APP_VERSION), optstr(APP_ENV), optstr(APP_REPO));
 }
-#ifndef PIO_UNIT_TESTING
+#if !defined(PIO_UNIT_TESTING) || !(PIO_UNIT_TESTING)
 void setup()
 {
 #if defined(R1_NEO)
@@ -1573,7 +1573,7 @@ void scannerToSensorsMap(const std::unique_ptr<ScanI2CTwoWire> &i2cScanner, Scan
 }
 #endif
 
-#ifndef PIO_UNIT_TESTING
+#if !defined(PIO_UNIT_TESTING) || !(PIO_UNIT_TESTING)
 void loop()
 {
     runASAP = false;
diff --git a/src/mesh/MemoryPool.h b/src/mesh/MemoryPool.h
index eb5ac5109d..0784d8c940 100644
--- a/src/mesh/MemoryPool.h
+++ b/src/mesh/MemoryPool.h
@@ -8,6 +8,10 @@
 #include "PointerQueue.h"
 #include "configuration.h" // For LOG_WARN, LOG_DEBUG, LOG_HEAP
 
+#if defined(ARCH_ESP32)
+#include <esp_heap_caps.h>
+#endif
+
 template <class T> class Allocator
 {
 
@@ -159,3 +163,92 @@ template <class T, int MaxSize> class MemoryPool : public Allocator<T>
         return nullptr;
     }
 };
+
+#if defined(ARCH_ESP32)
+// Simple fixed-size allocator that uses PSRAM. Used on ESP32-S3 builds so the
+// large MeshPacket pool can live off-chip and free internal RAM.
+template <class T, int MaxSize> class PsramMemoryPool : public Allocator<T>
+{
+  private:
+    T *pool;
+    bool used[MaxSize];
+
+  public:
+    PsramMemoryPool() : pool(nullptr), used{}
+    {
+        pool = static_cast<T *>(heap_caps_malloc(sizeof(T) * MaxSize, MALLOC_CAP_SPIRAM | MALLOC_CAP_8BIT));
+        if (pool) {
+            memset(pool, 0, sizeof(T) * MaxSize);
+        } else {
+            LOG_WARN("Failed to allocate PSRAM pool of %d elements", MaxSize);
+        }
+    }
+
+    ~PsramMemoryPool() override
+    {
+        if (pool) {
+            heap_caps_free(pool);
+        }
+    }
+
+    bool isValid() const { return pool != nullptr; }
+
+    void release(T *p) override
+    {
+        if (!pool || !p) {
+            LOG_DEBUG("Failed to release PSRAM memory, pointer is null or pool unavailable");
+            return;
+        }
+
+        int index = static_cast<int>(p - pool);
+        if (index >= 0 && index < MaxSize) {
+            assert(used[index]);
+            used[index] = false;
+            LOG_HEAP("Released PSRAM pool item %d at 0x%x", index, p);
+        } else {
+            LOG_WARN("Pointer 0x%x not from PSRAM pool!", p);
+        }
+    }
+
+  protected:
+    T *alloc(TickType_t maxWait) override
+    {
+        if (!pool)
+            return nullptr;
+
+        for (int i = 0; i < MaxSize; i++) {
+            if (!used[i]) {
+                used[i] = true;
+                LOG_HEAP("Allocated PSRAM pool item %d at 0x%x", i, &pool[i]);
+                return &pool[i];
+            }
+        }
+
+        LOG_WARN("No free slots available in PSRAM memory pool!");
+        return nullptr;
+    }
+};
+
+// Utility helpers for PSRAM-backed array allocations on ESP32 targets.
+template <typename T> inline T *psramAllocArray(size_t count)
+{
+    return static_cast<T *>(heap_caps_malloc(sizeof(T) * count, MALLOC_CAP_SPIRAM | MALLOC_CAP_8BIT));
+}
+
+template <typename T> inline void psramFreeArray(T *ptr)
+{
+    if (ptr)
+        heap_caps_free(ptr);
+}
+#else
+template <typename T> inline T *psramAllocArray(size_t count)
+{
+    (void)count;
+    return nullptr;
+}
+
+template <typename T> inline void psramFreeArray(T *ptr)
+{
+    (void)ptr;
+}
+#endif
diff --git a/src/mesh/MeshService.cpp b/src/mesh/MeshService.cpp
index 1b2af082d8..6b4504b058 100644
--- a/src/mesh/MeshService.cpp
+++ b/src/mesh/MeshService.cpp
@@ -305,15 +305,21 @@ void MeshService::sendToPhone(meshtastic_MeshPacket *p)
 #endif
 #endif
 
-    if (toPhoneQueue.numFree() == 0) {
+    // MAX_RX_TOPHONE is sized for PSRAM-backed builds. Fall back to a smaller
+    // runtime limit if the helper detects <2MB of PSRAM at boot.
+    const int queueLimit = get_rx_tophone_limit();
+    const bool runtimeLimitReached = queueLimit > 0 && toPhoneQueue.numUsed() >= queueLimit;
+
+    if (toPhoneQueue.numFree() == 0 || runtimeLimitReached) {
+        const bool runtimeControlled = runtimeLimitReached && queueLimit < MAX_RX_TOPHONE;
         if (p->decoded.portnum == meshtastic_PortNum_TEXT_MESSAGE_APP ||
             p->decoded.portnum == meshtastic_PortNum_RANGE_TEST_APP) {
-            LOG_WARN("ToPhone queue is full, discard oldest");
+            LOG_WARN("ToPhone queue %s, discard oldest", runtimeControlled ? "reached runtime limit" : "is full");
             meshtastic_MeshPacket *d = toPhoneQueue.dequeuePtr(0);
             if (d)
                 releaseToPool(d);
         } else {
-            LOG_WARN("ToPhone queue is full, drop packet");
+            LOG_WARN("ToPhone queue %s, drop packet", runtimeControlled ? "reached runtime limit" : "is full");
             releaseToPool(p);
             fromNum++; // Make sure to notify observers in case they are reconnected so they can get the packets
             return;
diff --git a/src/mesh/NodeDB.cpp b/src/mesh/NodeDB.cpp
index df9aece0ad..4cfad2b8fc 100644
--- a/src/mesh/NodeDB.cpp
+++ b/src/mesh/NodeDB.cpp
@@ -24,6 +24,7 @@
 #include "modules/NeighborInfoModule.h"
 #include <ErriezCRC32.h>
 #include <algorithm>
+#include <limits>
 #include <pb_decode.h>
 #include <pb_encode.h>
 #include <vector>
@@ -37,6 +38,12 @@
 #include <Preferences.h>
 #include <esp_efuse.h>
 #include <esp_efuse_table.h>
+#if __has_include(<esp_ptr.h>)
+#include <esp_ptr.h>
+#define NODEDB_HAS_ESP_PTR 1
+#else
+#define NODEDB_HAS_ESP_PTR 0
+#endif
 #include <nvs_flash.h>
 #include <soc/efuse_reg.h>
 #include <soc/soc.h>
@@ -67,6 +74,174 @@ meshtastic_DeviceUIConfig uiconfig{.screen_brightness = 153, .screen_timeout = 3
 meshtastic_LocalModuleConfig moduleConfig;
 meshtastic_ChannelFile channelFile;
 
+//------------------------------------------------------------------------------
+// Runtime instrumentation helpers
+//------------------------------------------------------------------------------
+
+namespace
+{
+
+// Log the pool headroom every 100 inserts (and when we hit MAX) so field logs
+// capture how close we are to exhausting heap/PSRAM on real hardware.
+
+void logNodeInsertStats(size_t count, const char *poolLabel)
+{
+    if (count == 0)
+        return;
+    if ((count % 100) != 0 && count != MAX_NUM_NODES)
+        return;
+
+    LOG_INFO("NodeDB %s pool usage %u/%u nodes, heap free %u, psram free %u", poolLabel, static_cast<unsigned>(count),
+             static_cast<unsigned>(MAX_NUM_NODES), memGet.getFreeHeap(), memGet.getFreePsram());
+}
+
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+bool logPsramAllocationOnce(void *ptr, size_t capacity)
+{
+    static bool logged = false;
+    if (logged || !ptr)
+        return logged;
+
+#if NODEDB_HAS_ESP_PTR
+    bool inPsram = esp_ptr_external_ram(ptr);
+#else
+    bool inPsram = false;
+#endif
+    LOG_INFO("NodeDB PSRAM backing at %p (%s) capacity %u entries (~%u bytes)", ptr, inPsram ? "PSRAM" : "DRAM",
+             static_cast<unsigned>(capacity), static_cast<unsigned>(capacity * sizeof(meshtastic_NodeInfoLite)));
+    logged = true;
+    return logged;
+}
+#endif
+
+} // namespace
+
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+
+void NodeDB::initHotCache()
+{
+    // Pre-reserve the full cold store in PSRAM during boot so the high watermark
+    // shows up immediately in PSRAM usage logs and we avoid fragmented
+    // allocations later in the mission.
+    psramMeshNodes.resize(MAX_NUM_NODES);
+    hotNodes.resize(MAX_NUM_NODES);
+    hotDirty.assign(MAX_NUM_NODES, true);
+    meshNodes = &psramMeshNodes;
+    logPsramAllocationOnce(psramMeshNodes.data(), psramMeshNodes.capacity());
+}
+
+void NodeDB::refreshHotCache()
+{
+    for (size_t i = 0; i < numMeshNodes; ++i) {
+        if (hotDirty[i])
+            syncHotFromCold(i);
+    }
+}
+
+void NodeDB::syncHotFromCold(size_t index)
+{
+    if (index >= psramMeshNodes.size())
+        return;
+
+    const meshtastic_NodeInfoLite &node = psramMeshNodes[index];
+    NodeHotEntry &hot = hotNodes[index];
+
+    hot.num = node.num;
+    hot.last_heard = node.last_heard;
+    hot.snr = node.snr;
+    hot.channel = node.channel;
+    hot.next_hop = node.next_hop;
+    hot.role = static_cast<uint8_t>(node.user.role);
+    hot.hops_away = node.hops_away;
+
+    uint8_t flags = 0;
+    if (node.via_mqtt)
+        flags |= HOT_FLAG_VIA_MQTT;
+    if (node.is_favorite)
+        flags |= HOT_FLAG_IS_FAVORITE;
+    if (node.is_ignored)
+        flags |= HOT_FLAG_IS_IGNORED;
+    if (node.has_hops_away)
+        flags |= HOT_FLAG_HAS_HOPS;
+    if (node.bitfield & NODEINFO_BITFIELD_IS_KEY_MANUALLY_VERIFIED_MASK)
+        flags |= HOT_FLAG_IS_KEY_VERIFIED;
+    hot.flags = flags;
+
+    hotDirty[index] = false;
+}
+
+void NodeDB::markHotDirty(size_t index)
+{
+    if (index < hotDirty.size())
+        hotDirty[index] = true;
+}
+
+void NodeDB::markHotDirty(const meshtastic_NodeInfoLite *ptr)
+{
+    size_t idx = indexOf(ptr);
+    if (idx != std::numeric_limits<size_t>::max())
+        markHotDirty(idx);
+}
+
+void NodeDB::clearSlot(size_t index)
+{
+    if (index >= psramMeshNodes.size())
+        return;
+
+    psramMeshNodes[index] = {};
+    hotNodes[index] = NodeHotEntry{};
+    hotDirty[index] = false;
+}
+
+void NodeDB::swapSlots(size_t a, size_t b)
+{
+    if (a == b)
+        return;
+
+    std::swap(psramMeshNodes[a], psramMeshNodes[b]);
+    std::swap(hotNodes[a], hotNodes[b]);
+    std::swap(hotDirty[a], hotDirty[b]);
+}
+
+void NodeDB::copySlot(size_t src, size_t dst)
+{
+    if (src == dst)
+        return;
+
+    psramMeshNodes[dst] = psramMeshNodes[src];
+    hotNodes[dst] = hotNodes[src];
+    hotDirty[dst] = hotDirty[src];
+}
+
+void NodeDB::moveSlot(size_t src, size_t dst)
+{
+    if (src == dst)
+        return;
+
+    copySlot(src, dst);
+    clearSlot(src);
+}
+
+bool NodeDB::isNodeEmpty(const meshtastic_NodeInfoLite &node) const
+{
+    return node.num == 0 && !node.has_user && !node.has_position && !node.has_device_metrics && !node.is_favorite &&
+           !node.is_ignored && node.last_heard == 0 && node.channel == 0 && node.next_hop == 0 && node.bitfield == 0;
+}
+
+size_t NodeDB::indexOf(const meshtastic_NodeInfoLite *ptr) const
+{
+    if (!ptr || psramMeshNodes.empty())
+        return std::numeric_limits<size_t>::max();
+
+    const meshtastic_NodeInfoLite *base = psramMeshNodes.data();
+    size_t idx = static_cast<size_t>(ptr - base);
+    if (idx >= psramMeshNodes.size())
+        return std::numeric_limits<size_t>::max();
+    return idx;
+}
+
+#endif
+
 #ifdef USERPREFS_USE_ADMIN_KEY_0
 static unsigned char userprefs_admin_key_0[] = USERPREFS_USE_ADMIN_KEY_0;
 #endif
@@ -520,9 +695,16 @@ void NodeDB::installDefaultNodeDatabase()
 {
     LOG_DEBUG("Install default NodeDatabase");
     nodeDatabase.version = DEVICESTATE_CUR_VER;
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+    initHotCache();
+    for (size_t i = 0; i < psramMeshNodes.size(); ++i)
+        clearSlot(i);
+    nodeDatabase.nodes.clear();
+#else
     nodeDatabase.nodes = std::vector<meshtastic_NodeInfoLite>(MAX_NUM_NODES);
-    numMeshNodes = 0;
     meshNodes = &nodeDatabase.nodes;
+#endif
+    numMeshNodes = 0;
 }
 
 void NodeDB::installDefaultConfig(bool preserveKey = false)
@@ -988,8 +1170,18 @@ void NodeDB::resetNodes()
 {
     if (!config.position.fixed_position)
         clearLocalPosition();
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+    if (psramMeshNodes.empty())
+        initHotCache();
+    numMeshNodes = std::min<pb_size_t>(numMeshNodes, MAX_NUM_NODES);
+    if (numMeshNodes == 0)
+        numMeshNodes = 1;
+    for (size_t i = 1; i < psramMeshNodes.size(); ++i)
+        clearSlot(i);
+#else
     numMeshNodes = 1;
     std::fill(nodeDatabase.nodes.begin() + 1, nodeDatabase.nodes.end(), meshtastic_NodeInfoLite());
+#endif
     devicestate.has_rx_text_message = false;
     devicestate.has_rx_waypoint = false;
     saveNodeDatabaseToDisk();
@@ -1000,7 +1192,25 @@ void NodeDB::resetNodes()
 
 void NodeDB::removeNodeByNum(NodeNum nodeNum)
 {
-    int newPos = 0, removed = 0;
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+    refreshHotCache();
+    int newPos = 0;
+    int removed = 0;
+    for (int i = 0; i < numMeshNodes; i++) {
+        if (hotNodes[i].num != nodeNum) {
+            if (newPos != i)
+                moveSlot(i, newPos);
+            newPos++;
+        } else {
+            removed++;
+        }
+    }
+    for (int i = newPos; i < numMeshNodes; i++)
+        clearSlot(i);
+    numMeshNodes -= removed;
+#else
+    int newPos = 0;
+    int removed = 0;
     for (int i = 0; i < numMeshNodes; i++) {
         if (meshNodes->at(i).num != nodeNum)
             meshNodes->at(newPos++) = meshNodes->at(i);
@@ -1010,6 +1220,7 @@ void NodeDB::removeNodeByNum(NodeNum nodeNum)
     numMeshNodes -= removed;
     std::fill(nodeDatabase.nodes.begin() + numMeshNodes, nodeDatabase.nodes.begin() + numMeshNodes + 1,
               meshtastic_NodeInfoLite());
+#endif
     LOG_DEBUG("NodeDB::removeNodeByNum purged %d entries. Save changes", removed);
     saveNodeDatabaseToDisk();
 }
@@ -1026,6 +1237,29 @@ void NodeDB::clearLocalPosition()
 
 void NodeDB::cleanupMeshDB()
 {
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+    refreshHotCache();
+    int newPos = 0, removed = 0;
+    for (int i = 0; i < numMeshNodes; i++) {
+        auto &node = psramMeshNodes[i];
+        if (node.has_user) {
+            if (node.user.public_key.size > 0) {
+                if (memfll(node.user.public_key.bytes, 0, node.user.public_key.size)) {
+                    node.user.public_key.size = 0;
+                    markHotDirty(i);
+                }
+            }
+            if (newPos != i)
+                moveSlot(i, newPos);
+            newPos++;
+        } else {
+            removed++;
+        }
+    }
+    for (int i = newPos; i < numMeshNodes; i++)
+        clearSlot(i);
+    numMeshNodes -= removed;
+#else
     int newPos = 0, removed = 0;
     for (int i = 0; i < numMeshNodes; i++) {
         if (meshNodes->at(i).has_user) {
@@ -1045,6 +1279,7 @@ void NodeDB::cleanupMeshDB()
     numMeshNodes -= removed;
     std::fill(nodeDatabase.nodes.begin() + numMeshNodes, nodeDatabase.nodes.begin() + numMeshNodes + removed,
               meshtastic_NodeInfoLite());
+#endif
     LOG_DEBUG("cleanupMeshDB purged %d entries", removed);
 }
 
@@ -1198,16 +1433,41 @@ void NodeDB::loadFromDisk()
         LOG_WARN("NodeDatabase %d is old, discard", nodeDatabase.version);
         installDefaultNodeDatabase();
     } else {
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+        initHotCache();
+        size_t inserted = 0;
+        for (const auto &n : nodeDatabase.nodes) {
+            if (inserted >= MAX_NUM_NODES)
+                break;
+            if (isNodeEmpty(n))
+                continue;
+            psramMeshNodes[inserted] = n;
+            hotDirty[inserted] = true;
+            syncHotFromCold(inserted);
+            ++inserted;
+        }
+        for (size_t i = inserted; i < psramMeshNodes.size(); ++i)
+            clearSlot(i);
+        numMeshNodes = inserted;
+        nodeDatabase.nodes.clear();
+        LOG_INFO("Loaded saved nodedatabase version %d, with active nodes: %u", nodeDatabase.version, inserted);
+#else
         meshNodes = &nodeDatabase.nodes;
         numMeshNodes = nodeDatabase.nodes.size();
         LOG_INFO("Loaded saved nodedatabase version %d, with nodes count: %d", nodeDatabase.version, nodeDatabase.nodes.size());
+#endif
     }
 
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+    if (numMeshNodes > MAX_NUM_NODES)
+        numMeshNodes = MAX_NUM_NODES;
+#else
     if (numMeshNodes > MAX_NUM_NODES) {
         LOG_WARN("Node count %d exceeds MAX_NUM_NODES %d, truncating", numMeshNodes, MAX_NUM_NODES);
         numMeshNodes = MAX_NUM_NODES;
     }
     meshNodes->resize(MAX_NUM_NODES);
+#endif
 
     // static DeviceState scratch; We no longer read into a tempbuf because this structure is 15KB of valuable RAM
     state = loadProto(deviceStateFileName, meshtastic_DeviceState_size, sizeof(meshtastic_DeviceState),
@@ -1413,10 +1673,21 @@ bool NodeDB::saveNodeDatabaseToDisk()
     spiLock->lock();
     FSCom.mkdir("/prefs");
     spiLock->unlock();
+#endif
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+    nodeDatabase.nodes.clear();
+    nodeDatabase.nodes.reserve(numMeshNodes);
+    for (size_t i = 0; i < numMeshNodes; ++i) {
+        nodeDatabase.nodes.push_back(psramMeshNodes[i]);
+    }
 #endif
     size_t nodeDatabaseSize;
     pb_get_encoded_size(&nodeDatabaseSize, meshtastic_NodeDatabase_fields, &nodeDatabase);
-    return saveProto(nodeDatabaseFileName, nodeDatabaseSize, &meshtastic_NodeDatabase_msg, &nodeDatabase, false);
+    bool success = saveProto(nodeDatabaseFileName, nodeDatabaseSize, &meshtastic_NodeDatabase_msg, &nodeDatabase, false);
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+    nodeDatabase.nodes.clear();
+#endif
+    return success;
 }
 
 bool NodeDB::saveToDiskNoRetry(int saveWhat)
@@ -1497,10 +1768,18 @@ bool NodeDB::saveToDisk(int saveWhat)
 
 const meshtastic_NodeInfoLite *NodeDB::readNextMeshNode(uint32_t &readIndex)
 {
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+    if (readIndex < numMeshNodes) {
+        markHotDirty(readIndex);
+        return &psramMeshNodes[readIndex++];
+    }
+    return NULL;
+#else
     if (readIndex < numMeshNodes)
         return &meshNodes->at(readIndex++);
     else
         return NULL;
+#endif
 }
 
 /// Given a node, return how many seconds in the past (vs now) that we last heard from it
@@ -1533,12 +1812,27 @@ size_t NodeDB::getNumOnlineMeshNodes(bool localOnly)
     size_t numseen = 0;
 
     // FIXME this implementation is kinda expensive
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+    refreshHotCache();
+    uint32_t now = getTime();
+    for (int i = 0; i < numMeshNodes; i++) {
+        const NodeHotEntry &hot = hotNodes[i];
+        if (localOnly && (hot.flags & HOT_FLAG_VIA_MQTT))
+            continue;
+        int delta = static_cast<int>(now - hot.last_heard);
+        if (delta < 0)
+            delta = 0;
+        if (delta < NUM_ONLINE_SECS)
+            numseen++;
+    }
+#else
     for (int i = 0; i < numMeshNodes; i++) {
         if (localOnly && meshNodes->at(i).via_mqtt)
             continue;
         if (sinceLastSeen(&meshNodes->at(i)) < NUM_ONLINE_SECS)
             numseen++;
     }
+#endif
 
     return numseen;
 }
@@ -1654,6 +1948,13 @@ void NodeDB::addFromContact(meshtastic_SharedContact contact)
         sortMeshDB();
         notifyObservers(true); // Force an update whether or not our node counts have changed
     }
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+    {
+        size_t idx = indexOf(info);
+        if (idx != std::numeric_limits<size_t>::max())
+            syncHotFromCold(idx);
+    }
+#endif
     saveNodeDatabaseToDisk();
 }
 
@@ -1716,6 +2017,14 @@ bool NodeDB::updateUser(uint32_t nodeId, meshtastic_User &p, uint8_t channelInde
               info->channel);
     info->has_user = true;
 
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+    {
+        size_t idx = indexOf(info);
+        if (idx != std::numeric_limits<size_t>::max())
+            syncHotFromCold(idx);
+    }
+#endif
+
     if (changed) {
         updateGUIforNode = info;
         notifyObservers(true); // Force an update whether or not our node counts have changed
@@ -1763,6 +2072,13 @@ void NodeDB::updateFrom(const meshtastic_MeshPacket &mp)
             info->has_hops_away = true;
             info->hops_away = mp.hop_start - mp.hop_limit;
         }
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+        {
+            size_t idx = indexOf(info);
+            if (idx != std::numeric_limits<size_t>::max())
+                syncHotFromCold(idx);
+        }
+#endif
         sortMeshDB();
     }
 }
@@ -1772,6 +2088,11 @@ void NodeDB::set_favorite(bool is_favorite, uint32_t nodeId)
     meshtastic_NodeInfoLite *lite = getMeshNode(nodeId);
     if (lite && lite->is_favorite != is_favorite) {
         lite->is_favorite = is_favorite;
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+        size_t idx = indexOf(lite);
+        if (idx != std::numeric_limits<size_t>::max())
+            syncHotFromCold(idx);
+#endif
         sortMeshDB();
         saveNodeDatabaseToDisk();
     }
@@ -1785,12 +2106,21 @@ bool NodeDB::isFavorite(uint32_t nodeId)
     if (nodeId == NODENUM_BROADCAST)
         return false;
 
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+    refreshHotCache();
+    for (int i = 0; i < numMeshNodes; ++i) {
+        if (hotNodes[i].num == nodeId)
+            return (hotNodes[i].flags & HOT_FLAG_IS_FAVORITE) != 0;
+    }
+    return false;
+#else
     meshtastic_NodeInfoLite *lite = getMeshNode(nodeId);
 
     if (lite) {
         return lite->is_favorite;
     }
     return false;
+#endif
 }
 
 bool NodeDB::isFromOrToFavoritedNode(const meshtastic_MeshPacket &p)
@@ -1804,11 +2134,33 @@ bool NodeDB::isFromOrToFavoritedNode(const meshtastic_MeshPacket &p)
     if (p.to == NODENUM_BROADCAST)
         return isFavorite(p.from); // we never store NODENUM_BROADCAST in the DB, so we only need to check p.from
 
-    meshtastic_NodeInfoLite *lite = NULL;
-
     bool seenFrom = false;
     bool seenTo = false;
 
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+    refreshHotCache();
+    for (int i = 0; i < numMeshNodes; i++) {
+        const NodeHotEntry &hot = hotNodes[i];
+
+        if (hot.num == p.from) {
+            if (hot.flags & HOT_FLAG_IS_FAVORITE)
+                return true;
+
+            seenFrom = true;
+        }
+
+        if (hot.num == p.to) {
+            if (hot.flags & HOT_FLAG_IS_FAVORITE)
+                return true;
+
+            seenTo = true;
+        }
+
+        if (seenFrom && seenTo)
+            return false; // we've seen both, and neither is a favorite, so we can stop searching early
+    }
+#else
+    meshtastic_NodeInfoLite *lite = NULL;
     for (int i = 0; i < numMeshNodes; i++) {
         lite = &meshNodes->at(i);
 
@@ -1832,6 +2184,7 @@ bool NodeDB::isFromOrToFavoritedNode(const meshtastic_MeshPacket &p)
         // Note: if we knew that sortMeshDB was always called after any change to is_favorite, we could exit early after searching
         // all favorited nodes first.
     }
+#endif
 
     return false;
 }
@@ -1848,6 +2201,27 @@ void NodeDB::sortMeshDB()
         bool changed = true;
         while (changed) { // dumb reverse bubble sort, but probably not bad for what we're doing
             changed = false;
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+            refreshHotCache();
+            for (int i = numMeshNodes - 1; i > 0; i--) { // lowest case this should examine is i == 1
+                NodeHotEntry &prev = hotNodes[i - 1];
+                NodeHotEntry &curr = hotNodes[i];
+                if (prev.num == getNodeNum()) {
+                    continue;
+                } else if (curr.num == getNodeNum()) {
+                    swapSlots(i, i - 1);
+                    changed = true;
+                } else if ((curr.flags & HOT_FLAG_IS_FAVORITE) && !(prev.flags & HOT_FLAG_IS_FAVORITE)) {
+                    swapSlots(i, i - 1);
+                    changed = true;
+                } else if (!(curr.flags & HOT_FLAG_IS_FAVORITE) && (prev.flags & HOT_FLAG_IS_FAVORITE)) {
+                    continue;
+                } else if (curr.last_heard > prev.last_heard) {
+                    swapSlots(i, i - 1);
+                    changed = true;
+                }
+            }
+#else
             for (int i = numMeshNodes - 1; i > 0; i--) { // lowest case this should examine is i == 1
                 if (meshNodes->at(i - 1).num == getNodeNum()) {
                     // noop
@@ -1866,6 +2240,7 @@ void NodeDB::sortMeshDB()
                     changed = true;
                 }
             }
+#endif
         }
         LOG_INFO("Sort took %u milliseconds", millis() - lastSort);
     }
@@ -1873,11 +2248,20 @@ void NodeDB::sortMeshDB()
 
 uint8_t NodeDB::getMeshNodeChannel(NodeNum n)
 {
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+    refreshHotCache();
+    for (int i = 0; i < numMeshNodes; ++i) {
+        if (hotNodes[i].num == n)
+            return hotNodes[i].channel;
+    }
+    return 0;
+#else
     const meshtastic_NodeInfoLite *info = getMeshNode(n);
     if (!info) {
         return 0; // defaults to PRIMARY
     }
     return info->channel;
+#endif
 }
 
 std::string NodeDB::getNodeId() const
@@ -1891,11 +2275,21 @@ std::string NodeDB::getNodeId() const
 /// NOTE: This function might be called from an ISR
 meshtastic_NodeInfoLite *NodeDB::getMeshNode(NodeNum n)
 {
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+    for (int i = 0; i < numMeshNodes; i++) {
+        if (hotNodes[i].num == n) {
+            markHotDirty(i);
+            return &psramMeshNodes[i];
+        }
+    }
+    return NULL;
+#else
     for (int i = 0; i < numMeshNodes; i++)
         if (meshNodes->at(i).num == n)
             return &meshNodes->at(i);
 
     return NULL;
+#endif
 }
 
 // returns true if the maximum number of nodes is reached or we are running low on memory
@@ -1907,6 +2301,60 @@ bool NodeDB::isFull()
 /// Find a node in our DB, create an empty NodeInfo if missing
 meshtastic_NodeInfoLite *NodeDB::getOrCreateMeshNode(NodeNum n)
 {
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+    meshtastic_NodeInfoLite *lite = getMeshNode(n);
+
+    if (!lite) {
+        if (isFull()) {
+            LOG_INFO("Node database full with %i nodes and %u bytes free. Erasing oldest entry", numMeshNodes,
+                     memGet.getFreeHeap());
+            refreshHotCache();
+            uint32_t oldest = UINT32_MAX;
+            uint32_t oldestBoring = UINT32_MAX;
+            int oldestIndex = -1;
+            int oldestBoringIndex = -1;
+            for (int i = 1; i < numMeshNodes; i++) {
+                const NodeHotEntry &hot = hotNodes[i];
+                if (!(hot.flags & HOT_FLAG_IS_FAVORITE) && !(hot.flags & HOT_FLAG_IS_IGNORED) &&
+                    !(hot.flags & HOT_FLAG_IS_KEY_VERIFIED) && hot.last_heard < oldest) {
+                    oldest = hot.last_heard;
+                    oldestIndex = i;
+                }
+                const auto &coldNode = psramMeshNodes[i];
+                if (!(hot.flags & HOT_FLAG_IS_FAVORITE) && !(hot.flags & HOT_FLAG_IS_IGNORED) &&
+                    coldNode.user.public_key.size == 0 && hot.last_heard < oldestBoring) {
+                    oldestBoring = hot.last_heard;
+                    oldestBoringIndex = i;
+                }
+            }
+            if (oldestBoringIndex != -1)
+                oldestIndex = oldestBoringIndex;
+
+            if (oldestIndex != -1) {
+                for (int i = oldestIndex; i < numMeshNodes - 1; i++)
+                    copySlot(i + 1, i);
+                clearSlot(numMeshNodes - 1);
+                (numMeshNodes)--;
+            }
+        }
+
+        if (numMeshNodes >= MAX_NUM_NODES) {
+            LOG_WARN("Unable to allocate new node %u, MAX_NUM_NODES reached", static_cast<unsigned>(n));
+            return NULL;
+        }
+
+        size_t index = numMeshNodes++;
+        clearSlot(index);
+        psramMeshNodes[index].num = n;
+        syncHotFromCold(index);
+        lite = &psramMeshNodes[index];
+        LOG_INFO("Adding node to database with %i nodes and %u bytes free!", numMeshNodes, memGet.getFreeHeap());
+        logNodeInsertStats(numMeshNodes, "PSRAM");
+    }
+
+    markHotDirty(lite);
+    return lite;
+#else
     meshtastic_NodeInfoLite *lite = getMeshNode(n);
 
     if (!lite) {
@@ -1953,9 +2401,11 @@ meshtastic_NodeInfoLite *NodeDB::getOrCreateMeshNode(NodeNum n)
         memset(lite, 0, sizeof(*lite));
         lite->num = n;
         LOG_INFO("Adding node to database with %i nodes and %u bytes free!", numMeshNodes, memGet.getFreeHeap());
+        logNodeInsertStats(numMeshNodes, "Heap");
     }
 
     return lite;
+#endif
 }
 
 /// Sometimes we will have Position objects that only have a time, so check for
diff --git a/src/mesh/NodeDB.h b/src/mesh/NodeDB.h
index e8724f2c95..fc65b76ac0 100644
--- a/src/mesh/NodeDB.h
+++ b/src/mesh/NodeDB.h
@@ -4,9 +4,13 @@
 #include <Arduino.h>
 #include <algorithm>
 #include <assert.h>
+#include <new>
 #include <pb_encode.h>
 #include <string>
 #include <vector>
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+#include <esp_heap_caps.h>
+#endif
 
 #include "MeshTypes.h"
 #include "NodeStatus.h"
@@ -14,6 +18,53 @@
 #include "mesh-pb-constants.h"
 #include "mesh/generated/meshtastic/mesh.pb.h" // For CriticalErrorCode
 
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+/**
+ * Custom allocator that redirects NodeInfoLite storage into PSRAM so that the
+ * heavy payload stays out of internal RAM on ESP32-S3 devices.
+ */
+template <class T> struct PsramAllocator {
+    using value_type = T;
+
+    PsramAllocator() noexcept = default;
+
+    template <class U> PsramAllocator(const PsramAllocator<U> &) noexcept {}
+
+    [[nodiscard]] T *allocate(std::size_t n)
+    {
+        void *ptr = heap_caps_malloc(n * sizeof(T), MALLOC_CAP_SPIRAM | MALLOC_CAP_8BIT);
+        if (!ptr)
+            throw std::bad_alloc();
+        return static_cast<T *>(ptr);
+    }
+
+    void deallocate(T *p, std::size_t) noexcept
+    {
+        if (p)
+            heap_caps_free(p);
+    }
+
+    template <class U> bool operator==(const PsramAllocator<U> &) const noexcept { return true; }
+    template <class U> bool operator!=(const PsramAllocator<U> &) const noexcept { return false; }
+};
+
+/** Lightweight DRAM copy of the latency-sensitive node fields. */
+struct NodeHotEntry {
+    uint32_t num = 0;
+    uint32_t last_heard = 0;
+    float snr = 0.0f;
+    uint8_t role = meshtastic_Config_DeviceConfig_Role_CLIENT;
+    uint8_t channel = 0;
+    uint8_t next_hop = 0;
+    uint8_t hops_away = 0;
+    uint8_t flags = 0; // bitmask, see NodeDB::HotFlags
+};
+
+using NodeInfoLiteVector = std::vector<meshtastic_NodeInfoLite, PsramAllocator<meshtastic_NodeInfoLite>>;
+#else
+using NodeInfoLiteVector = std::vector<meshtastic_NodeInfoLite>;
+#endif
+
 #if ARCH_PORTDUINO
 #include "PortduinoGlue.h"
 #endif
@@ -135,7 +186,7 @@ class NodeDB
     // Note: these two references just point into our static array we serialize to/from disk
 
   public:
-    std::vector<meshtastic_NodeInfoLite> *meshNodes;
+    NodeInfoLiteVector *meshNodes;
     bool updateGUI = false; // we think the gui should definitely be redrawn, screen will clear this once handled
     meshtastic_NodeInfoLite *updateGUIforNode = NULL; // if currently showing this node, we think you should update the GUI
     Observable<const meshtastic::NodeStatus *> newStatus;
@@ -245,7 +296,12 @@ class NodeDB
     meshtastic_NodeInfoLite *getMeshNodeByIndex(size_t x)
     {
         assert(x < numMeshNodes);
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+        markHotDirty(x);
+        return &psramMeshNodes[x];
+#else
         return &meshNodes->at(x);
+#endif
     }
 
     virtual meshtastic_NodeInfoLite *getMeshNode(NodeNum n);
@@ -330,6 +386,31 @@ class NodeDB
     bool saveDeviceStateToDisk();
     bool saveNodeDatabaseToDisk();
     void sortMeshDB();
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+    enum HotFlags : uint8_t {
+        HOT_FLAG_VIA_MQTT = 1 << 0,
+        HOT_FLAG_IS_FAVORITE = 1 << 1,
+        HOT_FLAG_IS_IGNORED = 1 << 2,
+        HOT_FLAG_HAS_HOPS = 1 << 3,
+        HOT_FLAG_IS_KEY_VERIFIED = 1 << 4
+    };
+
+    void initHotCache();
+    void refreshHotCache();
+    void syncHotFromCold(size_t index);
+    void markHotDirty(size_t index);
+    void markHotDirty(const meshtastic_NodeInfoLite *ptr);
+    void clearSlot(size_t index);
+    void swapSlots(size_t a, size_t b);
+    void copySlot(size_t src, size_t dst);
+    void moveSlot(size_t src, size_t dst);
+    bool isNodeEmpty(const meshtastic_NodeInfoLite &node) const;
+    size_t indexOf(const meshtastic_NodeInfoLite *ptr) const;
+
+    NodeInfoLiteVector psramMeshNodes;
+    std::vector<NodeHotEntry> hotNodes;
+    std::vector<bool> hotDirty;
+#endif
 };
 
 extern NodeDB *nodeDB;
@@ -372,4 +453,4 @@ extern uint32_t error_address;
      ModuleConfig_RangeTestConfig_size + ModuleConfig_SerialConfig_size + ModuleConfig_StoreForwardConfig_size +                 \
      ModuleConfig_TelemetryConfig_size + ModuleConfig_size)
 
-// Please do not remove this comment, it makes trunk and compiler happy at the same time.
\ No newline at end of file
+// Please do not remove this comment, it makes trunk and compiler happy at the same time.
diff --git a/src/mesh/PacketHistory.cpp b/src/mesh/PacketHistory.cpp
index b4af707ae8..cb839b59f9 100644
--- a/src/mesh/PacketHistory.cpp
+++ b/src/mesh/PacketHistory.cpp
@@ -1,4 +1,5 @@
 #include "PacketHistory.h"
+#include "MemoryPool.h"
 #include "configuration.h"
 #include "mesh-pb-constants.h"
 
@@ -16,32 +17,61 @@
 #define VERBOSE_PACKET_HISTORY 0     // Set to 1 for verbose logging, 2 for heavy debugging
 #define PACKET_HISTORY_TRACE_AGING 1 // Set to 1 to enable logging of the age of re/used history slots
 
-PacketHistory::PacketHistory(uint32_t size) : recentPacketsCapacity(0), recentPackets(NULL) // Initialize members
+PacketHistory::PacketHistory(uint32_t size)
+    : recentPacketsCapacity(0), recentPackets(NULL), recentPacketsInPsram(false) // Initialize members
 {
     if (size < 4 || size > PACKETHISTORY_MAX) { // Copilot suggested - makes sense
         LOG_WARN("Packet History - Invalid size %d, using default %d", size, PACKETHISTORY_MAX);
         size = PACKETHISTORY_MAX; // Use default size if invalid
     }
 
+    LOG_DEBUG("Packet History - pre-alloc heap %u psram %u", memGet.getFreeHeap(), memGet.getFreePsram());
+
     // Allocate memory for the recent packets array
     recentPacketsCapacity = size;
-    recentPackets = new PacketRecord[recentPacketsCapacity];
-    if (!recentPackets) { // No logging here, console/log probably uninitialized yet.
-        LOG_ERROR("Packet History - Memory allocation failed for size=%d entries / %d Bytes", size,
-                  sizeof(PacketRecord) * recentPacketsCapacity);
-        recentPacketsCapacity = 0; // mark allocation fail
-        return;                    // return early
+    if (has_psram()) {
+        // Prefer PSRAM so the large history pool stays out of internal RAM on ESP32-S3 builds.
+        recentPackets = psramAllocArray<PacketRecord>(recentPacketsCapacity);
+        if (recentPackets) {
+            memset(recentPackets, 0, sizeof(PacketRecord) * recentPacketsCapacity);
+            recentPacketsInPsram = true;
+            LOG_DEBUG("Packet History - allocated %u entries in PSRAM, free heap %u psram %u", recentPacketsCapacity,
+                      memGet.getFreeHeap(), memGet.getFreePsram());
+        } else {
+            LOG_WARN("Packet History - PSRAM allocation failed, falling back to DRAM");
+        }
     }
 
-    // Initialize the recent packets array to zero
-    memset(recentPackets, 0, sizeof(PacketRecord) * recentPacketsCapacity);
+    if (!recentPackets) {
+        // Fall back to DRAM if PSRAM is unavailable or exhausted.
+        recentPackets = new PacketRecord[recentPacketsCapacity];
+        if (!recentPackets) { // No logging here, console/log probably uninitialized yet.
+            LOG_ERROR("Packet History - Memory allocation failed for size=%d entries / %d Bytes", size,
+                      sizeof(PacketRecord) * recentPacketsCapacity);
+            recentPacketsCapacity = 0; // mark allocation fail
+            return;                    // return early
+        }
+
+        // Initialize the recent packets array to zero
+        memset(recentPackets, 0, sizeof(PacketRecord) * recentPacketsCapacity);
+        LOG_DEBUG("Packet History - allocated %u entries in DRAM, free heap %u psram %u", recentPacketsCapacity,
+                  memGet.getFreeHeap(), memGet.getFreePsram());
+    }
 }
 
 PacketHistory::~PacketHistory()
 {
-    recentPacketsCapacity = 0;
-    delete[] recentPackets;
+    if (recentPackets) {
+        // Release via the allocator that produced the buffer.
+        if (recentPacketsInPsram)
+            psramFreeArray(recentPackets);
+        else
+            delete[] recentPackets;
+    }
+
     recentPackets = NULL;
+    recentPacketsCapacity = 0;
+    recentPacketsInPsram = false;
 }
 
 /** Update recentPackets and return true if we have already seen this packet */
@@ -457,4 +487,4 @@ inline uint8_t PacketHistory::getOurTxHopLimit(PacketRecord &r)
 inline void PacketHistory::setOurTxHopLimit(PacketRecord &r, uint8_t hopLimit)
 {
     r.hop_limit = (r.hop_limit & ~HOP_LIMIT_OUR_TX_MASK) | ((hopLimit << HOP_LIMIT_OUR_TX_SHIFT) & HOP_LIMIT_OUR_TX_MASK);
-}
\ No newline at end of file
+}
diff --git a/src/mesh/PacketHistory.h b/src/mesh/PacketHistory.h
index 5fbad2dc94..4f06ed4e04 100644
--- a/src/mesh/PacketHistory.h
+++ b/src/mesh/PacketHistory.h
@@ -27,6 +27,7 @@ class PacketHistory
     uint32_t recentPacketsCapacity =
         0; // Can be set in constructor, no need to recompile. Used to allocate memory for mx_recentPackets.
     PacketRecord *recentPackets = NULL; // Simple and fixed in size. Debloat.
+    bool recentPacketsInPsram = false;  // Remember backing store so we free via the matching allocator.
 
     /** Find a packet record in history.
      * @param sender NodeNum
diff --git a/src/mesh/ProtobufModule.h b/src/mesh/ProtobufModule.h
index 725477eaee..8d71bc0b7e 100644
--- a/src/mesh/ProtobufModule.h
+++ b/src/mesh/ProtobufModule.h
@@ -120,4 +120,4 @@ template <class T> class ProtobufModule : protected SinglePortModule
             return alterReceivedProtobuf(mp, decoded);
         }
     }
-};
\ No newline at end of file
+};
diff --git a/src/mesh/Router.cpp b/src/mesh/Router.cpp
index 5cf8bfa7df..22d185552d 100644
--- a/src/mesh/Router.cpp
+++ b/src/mesh/Router.cpp
@@ -52,8 +52,21 @@ Allocator<meshtastic_MeshPacket> &packetPool = dynamicPool;
     (MAX_RX_TOPHONE + MAX_RX_FROMRADIO + 2 * MAX_TX_QUEUE +                                                                      \
      2) // max number of packets which can be in flight (either queued from reception or queued for sending)
 
+#if defined(CONFIG_IDF_TARGET_ESP32S3) && defined(BOARD_HAS_PSRAM)
+// Try to put the heavy MeshPacket pool into PSRAM. If that fails we fall back to
+// heap allocation so the radio stays functional (at the cost of fewer packets).
+static PsramMemoryPool<meshtastic_MeshPacket, MAX_PACKETS_STATIC> psramPool;
+static MemoryDynamic<meshtastic_MeshPacket> fallbackPool;
+Allocator<meshtastic_MeshPacket> &packetPool = psramPool.isValid()
+                                                   ? static_cast<Allocator<meshtastic_MeshPacket> &>(psramPool)
+                                                   : static_cast<Allocator<meshtastic_MeshPacket> &>(fallbackPool);
+#elif defined(CONFIG_IDF_TARGET_ESP32S3)
 static MemoryPool<meshtastic_MeshPacket, MAX_PACKETS_STATIC> staticPool;
 Allocator<meshtastic_MeshPacket> &packetPool = staticPool;
+#else
+static MemoryPool<meshtastic_MeshPacket, MAX_PACKETS_STATIC> staticPool;
+Allocator<meshtastic_MeshPacket> &packetPool = staticPool;
+#endif
 #endif
 
 static uint8_t bytes[MAX_LORA_PAYLOAD_LEN + 1] __attribute__((__aligned__));
diff --git a/src/mesh/mesh-pb-constants.h b/src/mesh/mesh-pb-constants.h
index e4f65aa283..0aaca57a5c 100644
--- a/src/mesh/mesh-pb-constants.h
+++ b/src/mesh/mesh-pb-constants.h
@@ -1,6 +1,7 @@
 #pragma once
 #include <vector>
 
+#include "memGet.h"
 #include "mesh/generated/meshtastic/admin.pb.h"
 #include "mesh/generated/meshtastic/deviceonly.pb.h"
 #include "mesh/generated/meshtastic/localonly.pb.h"
@@ -11,11 +12,58 @@
 // Tricky macro to let you find the sizeof a type member
 #define member_size(type, member) sizeof(((type *)0)->member)
 
+// Minimum PSRAM the firmware expects before enabling the "expanded" queues that
+// rely on off-chip RAM instead of internal DRAM. Currently set to 2MB to
+// accommodate Heltec WiFi LoRa 32 V4 boards (and others)
+static constexpr size_t PSRAM_LARGE_THRESHOLD_BYTES = 2 * 1024 * 1024;
+
+// Default RX queue size for phone delivery when PSRAM is available
+// This is an arbitrary default bump from default, boards can override
+// this in board.h
+static constexpr int RX_TOPHONE_WITH_PSRAM_DEFAULT = 100;
+
+inline bool has_psram(size_t minimumBytes = PSRAM_LARGE_THRESHOLD_BYTES)
+{
+#if defined(ARCH_ESP32) || defined(ARCH_PORTDUINO)
+    return memGet.getPsramSize() >= minimumBytes;
+#else
+    (void)minimumBytes;
+    return false;
+#endif
+}
+
+// Runtime cap used to keep the BLE message queue from overflowing low-memory
+// S3 variants if PSRAM is smaller than expected or temporarily unavailable.
+inline int get_rx_tophone_limit()
+{
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+#if defined(BOARD_MAX_RX_TOPHONE)
+    return BOARD_MAX_RX_TOPHONE;
+#elif defined(BOARD_HAS_PSRAM)
+    return RX_TOPHONE_WITH_PSRAM_DEFAULT;
+#else
+    return 32;
+#endif
+#elif defined(ARCH_ESP32) && !defined(CONFIG_IDF_TARGET_ESP32C3)
+    return 8;
+#else
+    return 32;
+#endif
+}
+
 /// max number of packets which can be waiting for delivery to android - note, this value comes from mesh.options protobuf
 // FIXME - max_count is actually 32 but we save/load this as one long string of preencoded MeshPacket bytes - not a big array in
 // RAM #define MAX_RX_TOPHONE (member_size(DeviceState, receive_queue) / member_size(DeviceState, receive_queue[0]))
 #ifndef MAX_RX_TOPHONE
-#if defined(ARCH_ESP32) && !(defined(CONFIG_IDF_TARGET_ESP32C3) || defined(CONFIG_IDF_TARGET_ESP32S3))
+#if defined(CONFIG_IDF_TARGET_ESP32S3)
+#if defined(BOARD_MAX_RX_TOPHONE)
+#define MAX_RX_TOPHONE BOARD_MAX_RX_TOPHONE
+#elif defined(BOARD_HAS_PSRAM)
+#define MAX_RX_TOPHONE RX_TOPHONE_WITH_PSRAM_DEFAULT
+#else
+#define MAX_RX_TOPHONE 32
+#endif
+#elif defined(ARCH_ESP32) && !defined(CONFIG_IDF_TARGET_ESP32C3)
 #define MAX_RX_TOPHONE 8
 #else
 #define MAX_RX_TOPHONE 32
@@ -48,19 +96,24 @@ static_assert(sizeof(meshtastic_NodeInfoLite) <= 200, "NodeInfoLite size increas
 #elif defined(ARCH_NRF52)
 #define MAX_NUM_NODES 80
 #elif defined(CONFIG_IDF_TARGET_ESP32S3)
+#if defined(BOARD_MAX_NUM_NODES)
+#define MAX_NUM_NODES BOARD_MAX_NUM_NODES
+#elif defined(BOARD_HAS_PSRAM)
+#define MAX_NUM_NODES 3000
+#else
 #include "Esp.h"
 static inline int get_max_num_nodes()
 {
-    uint32_t flash_size = ESP.getFlashChipSize() / (1024 * 1024); // Convert Bytes to MB
+    uint32_t flash_size = ESP.getFlashChipSize() / (1024 * 1024); // Fallback based on flash size
     if (flash_size >= 15) {
         return 250;
     } else if (flash_size >= 7) {
         return 200;
-    } else {
-        return 100;
     }
+    return 100;
 }
 #define MAX_NUM_NODES get_max_num_nodes()
+#endif
 #else
 #define MAX_NUM_NODES 100
 #endif
@@ -90,4 +143,4 @@ bool writecb(pb_ostream_t *stream, const uint8_t *buf, size_t count);
  */
 bool is_in_helper(uint32_t n, const uint32_t *array, pb_size_t count);
 
-#define is_in_repeated(name, n) is_in_helper(n, name, name##_count)
\ No newline at end of file
+#define is_in_repeated(name, n) is_in_helper(n, name, name##_count)
diff --git a/src/modules/AdminModule.cpp b/src/modules/AdminModule.cpp
index d300ff53b8..a72e429d38 100644
--- a/src/modules/AdminModule.cpp
+++ b/src/modules/AdminModule.cpp
@@ -327,9 +327,8 @@ bool AdminModule::handleReceivedProtobuf(const meshtastic_MeshPacket &mp, meshta
     }
     case meshtastic_AdminMessage_set_favorite_node_tag: {
         LOG_INFO("Client received set_favorite_node command");
-        meshtastic_NodeInfoLite *node = nodeDB->getMeshNode(r->set_favorite_node);
-        if (node != NULL) {
-            node->is_favorite = true;
+        if (nodeDB->getMeshNode(r->set_favorite_node) != NULL) {
+            nodeDB->set_favorite(true, r->set_favorite_node);
             saveChanges(SEGMENT_NODEDATABASE, false);
             if (screen)
                 screen->setFrames(graphics::Screen::FOCUS_PRESERVE); // <-- Rebuild screens
@@ -338,9 +337,8 @@ bool AdminModule::handleReceivedProtobuf(const meshtastic_MeshPacket &mp, meshta
     }
     case meshtastic_AdminMessage_remove_favorite_node_tag: {
         LOG_INFO("Client received remove_favorite_node command");
-        meshtastic_NodeInfoLite *node = nodeDB->getMeshNode(r->remove_favorite_node);
-        if (node != NULL) {
-            node->is_favorite = false;
+        if (nodeDB->getMeshNode(r->remove_favorite_node) != NULL) {
+            nodeDB->set_favorite(false, r->remove_favorite_node);
             saveChanges(SEGMENT_NODEDATABASE, false);
             if (screen)
                 screen->setFrames(graphics::Screen::FOCUS_PRESERVE); // <-- Rebuild screens