diff --git a/src/python/replay_merge.py b/src/python/replay_merge.py
index 27991cbd16..69c0bbba73 100755
--- a/src/python/replay_merge.py
+++ b/src/python/replay_merge.py
@@ -1,7 +1,8 @@
 #!/usr/bin/env python3
 # -*- coding: utf-8 -*-
 """Replay merges and their test results.
-The output appears in the .workdirs/ directory.
+The output appears in the `.workdirsf`/ directory.
+Logs appear in the `replay_logs/merges/` directory.
 Command-line arguments are listed just after the line:
   if __name__ == "__main__":
 
@@ -13,6 +14,7 @@
 import argparse
 import git
 import os
+import os.path
 import sys
 import tarfile
 from pathlib import Path
@@ -92,7 +94,22 @@ def merge_replay(
     plumelib_merging_dir = Path(ast_merging_evaluation_repo.working_tree_dir) / Path(
         "src/scripts/merge_tools/merging"
     )
-    subprocess.run(["./gradlew", "-q", "shadowJar"], cwd=plumelib_merging_dir)
+    print(f"About to compile in {plumelib_merging_dir}")
+    p = subprocess.run(
+        ["./gradlew", "-q", "shadowJar"],
+        cwd=plumelib_merging_dir,
+        capture_output=True,
+        text=True,
+    )
+    if p.returncode != 0:
+        print("Failure in: ./gradlew -q shadowJar")
+        print(p.stdout)
+        print(p.stderr)
+        sys.exit(1)
+    p = subprocess.run(
+        ["./gradlew", "-q", "nativeCompile"], cwd=plumelib_merging_dir, check=False
+    )
+    print("Finished compiling")
 
     result_df = pd.DataFrame()
     with Progress(
@@ -157,6 +174,7 @@ def merge_replay(
                     ["git", "merge-base", merge_data["left"], merge_data["right"]],
                     cwd=repo.local_repo_path,
                     stdout=subprocess.PIPE,
+                    check=True,
                 )
                 .stdout.decode("utf-8")
                 .strip()
diff --git a/src/python/repo.py b/src/python/repo.py
index b242a608a7..a514b95d3f 100755
--- a/src/python/repo.py
+++ b/src/python/repo.py
@@ -568,13 +568,18 @@ def merge(
             str(timeout),
             f"src/scripts/merge_tools/{tool.name}.sh {self.local_repo_path.resolve()} {LEFT_BRANCH_NAME} {RIGHT_BRANCH_NAME}",
         ]
+        logger.debug(
+            f"merge: Merging {self.repo_slug} {left_commit} {right_commit} with {tool.name}"
+        )
         p = subprocess.run(
             command,
             capture_output=True,
             check=False,
         )
+        std_streams = stdout_and_stderr(command, p)
+        logger.debug(std_streams)
         if p.returncode == 124:  # Timeout
-            explanation = explanation + "\n" + stdout_and_stderr(command, p)
+            explanation = explanation + "\n" + std_streams
             if use_cache:
                 cache_entry["merge status"] = MERGE_STATE.Merge_timedout.name
                 cache_entry["explanation"] = explanation
@@ -593,7 +598,7 @@ def merge(
                 -1,
             )
         run_time = time.time() - start_time
-        explanation = explanation + "\n" + stdout_and_stderr(command, p)
+        explanation = explanation + "\n" + std_streams
         merge_status = (
             MERGE_STATE.Merge_success if p.returncode == 0 else MERGE_STATE.Merge_failed
         )
diff --git a/src/scripts/merge_tools/merge_git_then_plumelib.sh b/src/scripts/merge_tools/merge_git_then_plumelib.sh
index 2edce670c3..fbed920b29 100755
--- a/src/scripts/merge_tools/merge_git_then_plumelib.sh
+++ b/src/scripts/merge_tools/merge_git_then_plumelib.sh
@@ -59,7 +59,11 @@ fi
 
 git config --local merge.tool merge-plumelib
 # shellcheck disable=SC2016
-git config --local mergetool.merge-plumelib.cmd 'merge-tool.sh '"$plumelib_strategy"' ${BASE} ${LOCAL} ${REMOTE} ${MERGED}'
+if [ -n "$VERBOSE" ] ; then
+  git config --local mergetool.merge-plumelib.cmd 'merge-tool.sh --verbose '"$plumelib_strategy"' ${LOCAL} ${BASE} ${REMOTE} ${MERGED}'
+else
+  git config --local mergetool.merge-plumelib.cmd 'merge-tool.sh '"$plumelib_strategy"' ${LOCAL} ${BASE} ${REMOTE} ${MERGED}'
+fi
 git config --local mergetool.merge-plumelib.trustExitCode true
 
 case "$plumelib_strategy" in
@@ -76,11 +80,11 @@ esac
 if [ -n "$VERBOSE" ] ; then
   echo "$0: about to run: git-mergetool.sh $all_arg --tool=merge-plumelib in $(pwd)"
   echo "$0: about to run: git-mergetool.sh $all_arg --tool=merge-plumelib in $(pwd)" >&2
-fi
-git-mergetool.sh $all_arg --tool=merge-plumelib
-if [ -n "$VERBOSE" ] ; then
+  git-mergetool.sh --verbose $all_arg --tool=merge-plumelib
   echo "$0: ran: git-mergetool.sh $all_arg --tool=merge-plumelib in $(pwd)"
   echo "$0: ran: git-mergetool.sh $all_arg --tool=merge-plumelib in $(pwd)" >&2
+else
+  git-mergetool.sh $all_arg --tool=merge-plumelib
 fi
 
 # Check if there are still conflicts
diff --git a/src/scripts/merge_tools/merge_script_then_plumelib.sh b/src/scripts/merge_tools/merge_script_then_plumelib.sh
index 42ef792ced..66baae69c1 100755
--- a/src/scripts/merge_tools/merge_script_then_plumelib.sh
+++ b/src/scripts/merge_tools/merge_script_then_plumelib.sh
@@ -60,7 +60,11 @@ fi
 
 git config --local merge.tool merge-plumelib
 # shellcheck disable=SC2016
-git config --local mergetool.merge-plumelib.cmd 'merge-tool.sh '"$plumelib_strategy"' ${BASE} ${LOCAL} ${REMOTE} ${MERGED}'
+if [ -n "$VERBOSE" ] ; then
+  git config --local mergetool.merge-plumelib.cmd 'merge-tool.sh --verbose '"$plumelib_strategy"' ${LOCAL} ${BASE} ${REMOTE} ${MERGED}'
+else
+  git config --local mergetool.merge-plumelib.cmd 'merge-tool.sh '"$plumelib_strategy"' ${LOCAL} ${BASE} ${REMOTE} ${MERGED}'
+fi
 git config --local mergetool.merge-plumelib.trustExitCode true
 
 case "$plumelib_strategy" in
diff --git a/src/scripts/merge_tools/merging b/src/scripts/merge_tools/merging
index 7d534cf30f..694e1ac7bd 160000
--- a/src/scripts/merge_tools/merging
+++ b/src/scripts/merge_tools/merging
@@ -1 +1 @@
-Subproject commit 7d534cf30fefb03962385372d7a8125ab97b3aac
+Subproject commit 694e1ac7bdb17a2631442405513e748c837a9f3b