diff --git a/src/backend/columnar/columnar_customscan.c b/src/backend/columnar/columnar_customscan.c
index 5e5410116..baf569464 100644
--- a/src/backend/columnar/columnar_customscan.c
+++ b/src/backend/columnar/columnar_customscan.c
@@ -16,6 +16,9 @@
 
 #include "miscadmin.h"
 
+#include "nodes/execnodes.h"     /* for ExprState, ExprContext, etc. */
+#include "executor/executor.h"   /* for ExecInitExprWithParams(), ExecEvalExpr() */
+#include "commands/explain_format.h"  /* for ExplainPropertyInteger() */
 #include "access/amapi.h"
 #include "access/skey.h"
 #include "catalog/pg_am.h"
diff --git a/src/backend/distributed/connection/worker_log_messages.c b/src/backend/distributed/connection/worker_log_messages.c
index 7bce64050..96ab36613 100644
--- a/src/backend/distributed/connection/worker_log_messages.c
+++ b/src/backend/distributed/connection/worker_log_messages.c
@@ -16,6 +16,7 @@
 #include "distributed/connection_management.h"
 #include "distributed/error_codes.h"
 #include "distributed/errormessage.h"
+#include "utils/memutils.h"   /* for TopTransactionContext */
 #include "distributed/log_utils.h"
 #include "distributed/worker_log_messages.h"
 
diff --git a/src/backend/distributed/planner/multi_explain.c b/src/backend/distributed/planner/multi_explain.c
index 9972adfee..023dc4718 100644
--- a/src/backend/distributed/planner/multi_explain.c
+++ b/src/backend/distributed/planner/multi_explain.c
@@ -23,6 +23,7 @@
 #include "commands/createas.h"
 #include "commands/dbcommands.h"
 #include "commands/explain.h"
+#include "commands/explain_format.h"
 #include "commands/tablecmds.h"
 #include "executor/tstoreReceiver.h"
 #include "lib/stringinfo.h"
@@ -42,6 +43,10 @@
 #include "utils/json.h"
 #include "utils/lsyscache.h"
 #include "utils/snapmgr.h"
+#if PG_VERSION_NUM >= PG_VERSION_18
+#  include "commands/explain_dr.h"   /* CreateExplainSerializeDestReceiver() */
+#endif
+
 
 #include "pg_version_constants.h"
 #if PG_VERSION_NUM >= PG_VERSION_18
diff --git a/src/backend/distributed/planner/multi_logical_planner.c b/src/backend/distributed/planner/multi_logical_planner.c
index d1e2e6bca..a42da71e9 100644
--- a/src/backend/distributed/planner/multi_logical_planner.c
+++ b/src/backend/distributed/planner/multi_logical_planner.c
@@ -34,6 +34,14 @@
 #include "utils/relcache.h"
 #include "utils/syscache.h"
 
+/*
+ * PG 18 renamed OpBtreeInterpretation to the more generic OpIndexInterpretation,
+ * so make the old name an alias.
+ */
+#if PG_VERSION_NUM >= PG_VERSION_18
+typedef OpIndexInterpretation OpBtreeInterpretation;
+#endif
+
 #include "pg_version_constants.h"
 #if PG_VERSION_NUM >= PG_VERSION_18
 typedef OpIndexInterpretation OpBtreeInterpretation;
diff --git a/src/backend/distributed/planner/shard_pruning.c b/src/backend/distributed/planner/shard_pruning.c
index 7e58d1154..1ed8a3e57 100644
--- a/src/backend/distributed/planner/shard_pruning.c
+++ b/src/backend/distributed/planner/shard_pruning.c
@@ -84,6 +84,14 @@
 #include "utils/memutils.h"
 #include "utils/ruleutils.h"
 
+/*
+ * PG 18 renamed OpBtreeInterpretation to the more generic OpIndexInterpretation,
+ * so make the old name an alias.
+ */
+#if PG_VERSION_NUM >= PG_VERSION_18
+typedef OpIndexInterpretation OpBtreeInterpretation;
+#endif
+
 #include "pg_version_constants.h"
 #if PG_VERSION_NUM >= PG_VERSION_18
 typedef OpIndexInterpretation OpBtreeInterpretation;