diff --git a/.cirrus.yml b/.cirrus.yml
index 398d45d2c8..39f4e8d49d 100644
--- a/.cirrus.yml
+++ b/.cirrus.yml
@@ -238,6 +238,7 @@ task:
   env:
     << : *CIRRUS_EPHEMERAL_WORKER_TEMPLATE_ENV
     FILE_ENV: "./ci/test/00_setup_env_native_tsan.sh"
+    MAKEJOBS: "-j2"  # Avoid excessive memory use due to MSan
 
 task:
   name: '[MSan, depends] [focal]'
@@ -247,7 +248,6 @@ task:
   env:
     << : *CIRRUS_EPHEMERAL_WORKER_TEMPLATE_ENV
     FILE_ENV: "./ci/test/00_setup_env_native_msan.sh"
-    MAKEJOBS: "-j4"  # Avoid excessive memory use due to MSan
 
 task:
   name: '[ASan + LSan + UBSan + integer, no depends, USDT] [jammy]'
@@ -265,7 +265,6 @@ task:
     << : *CIRRUS_EPHEMERAL_WORKER_TEMPLATE_ENV
     HOME: /root/  # Only needed for compute_engine_instance
     FILE_ENV: "./ci/test/00_setup_env_native_asan.sh"
-    MAKEJOBS: "-j4"  # Avoid excessive memory use
 
 task:
   name: '[fuzzer,address,undefined,integer, no depends] [jammy]'
diff --git a/src/chainparamsbase.h b/src/chainparamsbase.h
index 5ba4677ef3..2ebf859d72 100644
--- a/src/chainparamsbase.h
+++ b/src/chainparamsbase.h
@@ -5,6 +5,7 @@
 #ifndef BITCOIN_CHAINPARAMSBASE_H
 #define BITCOIN_CHAINPARAMSBASE_H
 
+#include <cstdint>
 #include <memory>
 #include <string>
 
diff --git a/src/node/interface_ui.h b/src/node/interface_ui.h
index 316d75167e..713d6711a8 100644
--- a/src/node/interface_ui.h
+++ b/src/node/interface_ui.h
@@ -6,9 +6,10 @@
 #ifndef BITCOIN_NODE_INTERFACE_UI_H
 #define BITCOIN_NODE_INTERFACE_UI_H
 
+#include <cstdint>
 #include <functional>
-#include <memory>
 #include <string>
+#include <vector>
 
 class CBlockIndex;
 enum class SynchronizationState;
diff --git a/src/test/system_tests.cpp b/src/test/system_tests.cpp
index 11f4be7fef..6764e2d24b 100644
--- a/src/test/system_tests.cpp
+++ b/src/test/system_tests.cpp
@@ -13,6 +13,12 @@
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wnarrowing"
 #endif
+#if defined(__GNUC__)
+// Boost 1.78 requires the following workaround.
+// See: https://github.com/boostorg/process/issues/235
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wnarrowing"
+#endif
 #include <boost/process.hpp>
 #if defined(__GNUC__)
 #pragma GCC diagnostic pop
diff --git a/src/util/system.cpp b/src/util/system.cpp
index 67658e3f77..cdc156d233 100644
--- a/src/util/system.cpp
+++ b/src/util/system.cpp
@@ -5,6 +5,19 @@
 
 #include <util/system.h>
 
+#ifdef ENABLE_EXTERNAL_SIGNER
+#if defined(__GNUC__)
+// Boost 1.78 requires the following workaround.
+// See: https://github.com/boostorg/process/issues/235
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wnarrowing"
+#endif
+#include <boost/process.hpp>
+#if defined(__GNUC__)
+#pragma GCC diagnostic pop
+#endif
+#endif // ENABLE_EXTERNAL_SIGNER
+
 #include <chainparamsbase.h>
 #include <fs.h>
 #include <sync.h>
diff --git a/src/zmq/zmqabstractnotifier.h b/src/zmq/zmqabstractnotifier.h
index 97c2599366..d29eaef9f3 100644
--- a/src/zmq/zmqabstractnotifier.h
+++ b/src/zmq/zmqabstractnotifier.h
@@ -5,6 +5,7 @@
 #ifndef BITCOIN_ZMQ_ZMQABSTRACTNOTIFIER_H
 #define BITCOIN_ZMQ_ZMQABSTRACTNOTIFIER_H
 
+
 #include <cstdint>
 #include <memory>
 #include <string>
diff --git a/src/zmq/zmqpublishnotifier.h b/src/zmq/zmqpublishnotifier.h
index fcedd1aabe..b95f4d6cfa 100644
--- a/src/zmq/zmqpublishnotifier.h
+++ b/src/zmq/zmqpublishnotifier.h
@@ -7,7 +7,6 @@
 
 #include <zmq/zmqabstractnotifier.h>
 
-#include <cstddef>
 #include <cstdint>
 
 class CBlockIndex;