diff --git a/builder/frameworks/base.py b/builder/frameworks/base.py
index c9317c23a..3a4209e21 100644
--- a/builder/frameworks/base.py
+++ b/builder/frameworks/base.py
@@ -20,8 +20,6 @@
 env.ParseCustomFlashLayout(platform, board)
 # Add flash layout C defines
 env.AddFlashLayout(board)
-# Write custom header options
-env.ApplyCustomOptions(platform)
 # Export board manifest for ltchiptool
 env.ExportBoardData(board)
 # Print information about versions and custom options
diff --git a/builder/utils/libs-queue.py b/builder/utils/libs-queue.py
index ddca5a27e..dc7064a07 100644
--- a/builder/utils/libs-queue.py
+++ b/builder/utils/libs-queue.py
@@ -184,6 +184,9 @@ def BuildLibraries(self):
         else:
             self.env.Append(CPPPATH=self.includes)
 
+        # prepend headers with custom options
+        self.env.ApplyCustomOptions(self.env.PioPlatform())
+
         # clone the environment for the whole library queue
         queue_env = self.env.Clone()
         # add private options to the cloned environment
diff --git a/cores/common/base/config/lwipopts.h b/cores/common/base/config/lwipopts.h
index 2557d02c8..5ce265028 100644
--- a/cores/common/base/config/lwipopts.h
+++ b/cores/common/base/config/lwipopts.h
@@ -15,8 +15,15 @@
 
 // set lwIP debugging options according to LT config
 #if LT_DEBUG_LWIP
+// enable main debugging switch
 #undef LWIP_DEBUG
 #define LWIP_DEBUG 1
+// enable all messages
+#undef LWIP_DBG_MIN_LEVEL
+#define LWIP_DBG_MIN_LEVEL 0
+// enable all debugging types
+#undef LWIP_DBG_TYPES_ON
+#define LWIP_DBG_TYPES_ON 0xF8
 // make lwIP use printf() library
 #include <stdio.h>
 #undef LWIP_PLATFORM_DIAG
diff --git a/docs/dev/config.md b/docs/dev/config.md
index bc668db2b..827ecd575 100644
--- a/docs/dev/config.md
+++ b/docs/dev/config.md
@@ -13,7 +13,10 @@ custom_fw_version = 1.2.0
 
 # custom build options (#defines, NOT compiler flags)
 custom_options.lwip =
-	LWIP_IPV4 = 1
+	# make sure to enable LT_DEBUG_LWIP as well
+	NETIF_DEBUG = 0x80
+    IP_DEBUG = 0x80
+    TCP_DEBUG = 0x80
 custom_options.freertos =
 	configUSE_TICK_HOOK = 1
 
@@ -82,7 +85,7 @@ To see debug messages from i.e. OTA, loglevel must also be changed.
 - `LT_DEBUG_OTA` (1) - OTA updates (`Update` library)
 - `LT_DEBUG_FDB` (0) - FlashDB debugging (macros within the library)
 - `LT_DEBUG_MDNS` (0) - mDNS client library
-- `LT_DEBUG_LWIP` (0) - enables `LWIP_DEBUG`, provides `LWIP_PLATFORM_DIAG`; per-module options (i.e. `TCP_DEBUG`) are off by default and need to be enabled separately
+- `LT_DEBUG_LWIP` (0) - enables `LWIP_DEBUG`, provides `LWIP_PLATFORM_DIAG`; per-module options (i.e. `TCP_DEBUG`) are off by default and need to be enabled separately - see example in `Project options` above
 - `LT_DEBUG_LWIP_ASSERT` (0) - enables assertions within lwIP (doesn't need `LT_DEBUG_LWIP`)
 
 !!! tip