diff --git a/tests/workflow/README.md b/tests/workflow/README.md
index b26309227..509670be3 100644
--- a/tests/workflow/README.md
+++ b/tests/workflow/README.md
@@ -77,6 +77,7 @@ Apply mutations only to a disposable checkout, run the named test without `--upd
 | `test_final_cat_merge_reads_every_ready_tile` | Drop one ready tile; append an out-of-scope tile. |
 | `test_products_use_products_dir_and_run_name` | Rename either merged catalogue or the persist manifest; route products to scratch; derive `CAMPAIGN` from the products directory's basename. |
 | `test_tile_store_is_unique_per_campaign` | Make `LOCAL_TAG` conditional on `image_sims` (or constant); give one tile_shape member a different store path. |
+| `test_module_logs_outlive_their_run_dirs` | Drop `post=` from tile_vignets or tile_ngmix; point the copy at `$SP_LOCAL` or `$SP_RUN/output`; move it after `exit $rc`. |
 | `test_missing_run_fails_during_parse` | Remove `run` from `run_config.REQUIRED`; literal paths must still receive the required-key diagnostic, not a later `KeyError`. |
 | `test_unit_pre_changes_at_campaign_boundary` | Append a line to `unit_pre`; change one rule's `params.pre`; change one shell; change a rendered thread count; make `LOCAL_TAG` empty for data. |
 | `test_params_pin_ignores_fixture_root` | Remove fixture-root or run-dir-hash normalization. |
diff --git a/tests/workflow/params_pin.json b/tests/workflow/params_pin.json
index 2284a7222..2e6ff6fe9 100644
--- a/tests/workflow/params_pin.json
+++ b/tests/workflow/params_pin.json
@@ -19,12 +19,12 @@
     "tile_make_cat": "1558e38ee60bf9d1e794c303567442b1d298898ab8d56bf1b30aa63974d212dd",
     "tile_merge_cats": "0783c93deeb7f90bdb9772bbc4117851dff1a671518c81f67edd4c7c79cc7e6a",
     "tile_merge_headers": "3e674f961fd5bb93ce1f3b0e2bb072a25a421f2828315a3db45a960c44a42111",
-    "tile_ngmix": "87618cc2318729e5c09d8f2915361f79a3fd0773d3eedd93cb9f94dcb3d97d5b",
+    "tile_ngmix": "5b83650fe8fdfaf24b6f1045cd418e816f2c5a9851e3e35852864772298ea26a",
     "tile_uncompress": "4a013cdd04bc3e3c1082e477161d2b03e0eefe280b1aabb9af25c149a977f55b",
-    "tile_vignets": "89d95bd9107c124e86dfb029d5ba2a2fc1871311a71a8fe18466302ef2213b14"
+    "tile_vignets": "1d434b4a6a4bcdeb8f1e5e9a5e4f228b67ade400245b41b033a2c883fb6a3267"
   },
   "schema": 1,
-  "sha256": "eab6930e0fd1044b9ce7a99172dbf9cbdcdec21291f8fa640d6e60c2efd3dd03",
+  "sha256": "782565d7614ad050cedec22e63b46d0913e8f14d931012d28343e76ba682af37",
   "unit_pre": {
     "exp_get_images": "dac6685a207dae3ea81d296ce53e9ba75d4636cf1f81e6399f2dda452680c992",
     "exp_psf": "87fc8ea1153a709ab7ba56542cfacc041f5f8b7f6cf2f38a9bc9d8004d1cecb4",
diff --git a/tests/workflow/test_dag.py b/tests/workflow/test_dag.py
index b23493ecc..35c06688e 100644
--- a/tests/workflow/test_dag.py
+++ b/tests/workflow/test_dag.py
@@ -145,6 +145,29 @@ def test_tile_store_is_unique_per_campaign(campaign, tmp_path, resolve_dag):
     assert all(first[tile] != second[tile] for tile in first), (first, second)
 
 
+def test_module_logs_outlive_their_run_dirs(campaign, dag):
+    """tile_vignets (node-local) and every ngmix chunk (temp()) copy their
+    module logs into the tile's logs/modules/ on the shared root, after
+    shapepipe_run and before the rule exits, whatever its rc."""
+    sources = {"tile_vignets": lambda job: '"$NGMIX_VIGNET_DIR"',
+               "tile_ngmix": lambda job: f'"{job.output.chunkdir}"'}
+    for rule, source in sources.items():
+        for job in dag.jobs_for(rule):
+            name = ("run_sp_tile_PiViVi" if rule == "tile_vignets" else
+                    f"run_sp_tile_ngmix_Ng{job.wildcards.chunk}u")
+            lines = job.shellcmd.splitlines()
+            keep = [i for i, line in enumerate(lines)
+                    if f'"$SP_RUN/logs/modules/{name}"' in line]
+            assert len(keep) == 1, (rule, job.wildcards_dict)
+            line = lines[keep[0]]
+            assert f"cd {source(job)}" in line
+            assert '-path "*/logs/*"' in line and line.rstrip().endswith(">&2")
+            run = next(i for i, l in enumerate(lines)
+                       if l.startswith("shapepipe_run "))
+            assert run < keep[0] < len(lines) - 1
+            assert lines[-1] == "exit $rc"
+
+
 def test_missing_run_fails_during_parse(campaign, resolve_dag):
     """Explicit paths cannot bypass the required campaign name diagnostic."""
     campaign.omit_run()
diff --git a/workflow/rules/tile.smk b/workflow/rules/tile.smk
index f607e3617..15a7bd3cc 100644
--- a/workflow/rules/tile.smk
+++ b/workflow/rules/tile.smk
@@ -346,6 +346,25 @@ fi
 
 
 
+# THE MODULE LOGS OUTLIVE THE RUN DIRS THAT HOLD THEM. A chunk's ShapePipe run
+# dir is temp() (tile_merge_cats is its last reader) and tile_vignets' lives in
+# the node-local store, so both kinds of log went with their dirs: the
+# run's own logs/ and each module's logs/process-*.log, where ngmix writes its
+# per-chunk `epoch cuts:` line and every per-object "ngmix failed" message.
+# The rule copies them to $SP_RUN/logs/modules/<run name>/ (the tile dir on the
+# shared root) before it exits, whatever its rc, so a failed chunk keeps its
+# evidence too. A few KB per chunk; clean_tile reclaims them with the rest of
+# logs/. The copy never changes the rule's exit status.
+def keep_module_logs(run_root, run_name):
+    dest = f'"$SP_RUN/logs/modules/{run_name}"'
+    return (
+        f'rm -rf {dest} && mkdir -p {dest} && '
+        f'(cd "{run_root}" && find . -path "*/logs/*" -type f '
+        f'-exec cp -p --parents -t {dest} {{{{}}}} +) || '
+        f'echo "could not keep the module logs of {run_root}" >&2\n'
+    )
+
+
 def tile_exp(wc):
     return tile_exposures(wc.tile)
 
@@ -612,7 +631,8 @@ rule tile_vignets:
         # The completeness check is pointed at the NODE-LOCAL run root; see
         # sp_shell's check_args for what the two flags do.
         sp_shell("tile_vignets", f"config_tile_PiViVi_{PSF_MODEL}.ini",
-                 check_args=' --run-dir "$SP_LOCAL" --unit {wildcards.tile}')
+                 check_args=' --run-dir "$SP_LOCAL" --unit {wildcards.tile}',
+                 post=keep_module_logs("$NGMIX_VIGNET_DIR", "run_sp_tile_PiViVi"))
 
 # ngmix shape measurement — N chunks per tile (D4). Each chunk LOOKS UP its own
 # CLOSED catalogue-row range in the file tile_vignets materialised at the top of this
@@ -828,7 +848,9 @@ rule tile_ngmix:
         runtime = lambda wc, attempt: 120 * attempt,
         slurm_extra = TILE_SLURM_EXTRA
     shell:
-        sp_shell("tile_ngmix", "config_tile_Ng_template.ini")
+        sp_shell("tile_ngmix", "config_tile_Ng_template.ini",
+                 post=keep_module_logs("{output.chunkdir}",
+                                       "run_sp_tile_ngmix_Ng{wildcards.chunk}u"))
 
 
 def ngmix_manifests(wc):