diff --git a/src/main.c b/src/main.c
index 363c8ec..7101a49 100644
--- a/src/main.c
+++ b/src/main.c
@@ -858,7 +858,7 @@ int main(int argc, char* argv[]) {
             */
 
             // Insert into txmempool
-            if (!TxMempool_Insert(spendTx)) {
+            if (TxMempool_Insert(spendTx) < 0) {
                 printf("failed to add transaction to mempool, transaction rejected\n");
                 continue;
             }
diff --git a/src/nets/net_node.c b/src/nets/net_node.c
index 2448bf4..9fe8888 100644
--- a/src/nets/net_node.c
+++ b/src/nets/net_node.c
@@ -239,6 +239,7 @@ net_node_t* Node_Create() {
     pthread_mutex_init(&node->seenLock, NULL);
     pthread_mutex_init(&node->outboundLock, NULL);
     node->seenBlocks = DynSet_Create(32); // 32-byte canonical hashes
+    TxMempool_Init();
 
     TcpServer_Init(node->server, listenPort, "0.0.0.0");
 
@@ -284,6 +285,7 @@ void Node_Destroy(net_node_t* node) {
     }
 
     OrphanPool_Destroy();
+    TxMempool_Destroy();
 
     if (node->seenBlocks) {
         DynSet_Destroy(node->seenBlocks);
@@ -639,7 +641,7 @@ void Node_Server_OnData(tcp_connection_t* client) {
 
                 // Push to mempool if it's not already present
                 if (!TxMempool_Lookup(txHash, &tx)) {
-                    if (TxMempool_Insert(tx) > 0) {
+                    if (TxMempool_Insert(tx) >= 0) {
                         printf("Added transaction %s from node %u to mempool\n", txHashHex, client ? client->connectionId : 0U);
                         // Broadcast to other peers
                         net_node_t* node = Node_FromConnection(client);