diff --git a/.github/workflows/cache_cleanup.yml b/.github/workflows/cache_cleanup.yml
index d72a512..aac9c54 100644
--- a/.github/workflows/cache_cleanup.yml
+++ b/.github/workflows/cache_cleanup.yml
@@ -18,7 +18,7 @@ jobs:
         # But for simplicity and safety we only work on the reported branch.
         # On the main branch this `cache_cleanup` workflow may not delete the last version as that
         # that would mean that the `test` workflow triggered for the same state will not find any
-        # caches. That is because the the `cache_cleanup` workflow is much faster and will most
+        # caches. That is because the `cache_cleanup` workflow is much faster and will most
         # likely finish during the initial `pre-commit` job of the `test` workflow.
         # Not that last version for the head ref means last cache version per cache key prefix.
         run: |
diff --git a/mbo/diff/README.md b/mbo/diff/README.md
index d1bd83b..b46fdb0 100644
--- a/mbo/diff/README.md
+++ b/mbo/diff/README.md
@@ -64,7 +64,6 @@ int main() {
 
   return 0;
 }
-
 ```
 
 ## 2. Command-Line Tool Reference: `unified_diff`
@@ -89,7 +88,6 @@ Build the tool with Bazel:
 
 ```bash
 bazel build //mbo/diff:unified_diff
-
 ```
 
 Perform a custom, whitespace-insensitive diff with 5 context lines:
@@ -100,7 +98,6 @@ Perform a custom, whitespace-insensitive diff with 5 context lines:
     --ignore-space-change \
     --ignore-blank-lines \
     path/to/original.txt path/to/modified.txt
-
 ```
 
 ## 3. Bazel Integration: `diff_test` Macro
@@ -148,12 +145,10 @@ diff_test(
     ignore_blank_lines = True,
     unified = 5,
 )
-
 ```
 
 Run the validation test with:
 
 ```bash
 bazel test //path/to/package:verify_config_generation
-
 ```
diff --git a/mbo/hash/README.md b/mbo/hash/README.md
index a97f919..ecb9594 100644
--- a/mbo/hash/README.md
+++ b/mbo/hash/README.md
@@ -313,8 +313,7 @@ Two views per hash width:
   is always represented; the unpredictable length order defeats the size-dispatch
   branch predictor, so the cost is measured, not modelled.
 
-Everything between the markers is generated per machine by `publish` from the
-committed bundles - regenerate it, don't hand-edit:
+<!-- IMPORTANT: Everything between the markers is generated per machine by `publish` from the committed bundles - regenerate it, don't hand-edit! -->
 
 <!-- BEGIN mbo/hash benchmark results (generated by `hash_benchmark_report.py publish`; DO NOT EDIT) -->
 <!-- bundles: mbo/hash/measurements/data/linux-x86-64-amd-ryzen-9-9950x-16-core-processor_10c_clang-22_29b54ccd_20260716_194643.tgz mbo/hash/measurements/data/linux-x86-64-amd-ryzen-9-9950x-16-core-processor_10c_gcc-15_29b54ccd_20260715_182532.tgz mbo/hash/measurements/data/macos-arm64-apple-m5-pro_18c_clang-21_29b54ccd_20260715_191140.tgz -->
@@ -323,6 +322,11 @@ committed bundles - regenerate it, don't hand-edit:
 
 <!-- AMD Ryzen 9 9950X 16-Core Processor · Linux · x86_64 · 10-core · clang-22 · 29b54ccd; mean of the 3 best of 9 reps -->
 
+#### Extra build configuration
+
+- **config**: `clang`
+- **copt**: `-march=znver5`
+
 ![mbo/hash 64-bit latency, AMD Ryzen 9 9950X 16-Core Processor · Linux · x86_64 · 10-core · clang-22 · 29b54ccd](measurements/charts/linux-x86-64-amd-ryzen-9-9950x-16-core-processor_clang-22_latency64.svg)
 
 #### 64-bit latency (ns/hash at exact length, mean of the 3 best of 9 reps; lower is better)
diff --git a/mbo/hash/measurements/hash_benchmark_report.py b/mbo/hash/measurements/hash_benchmark_report.py
index 67a5f89..9a8d40f 100755
--- a/mbo/hash/measurements/hash_benchmark_report.py
+++ b/mbo/hash/measurements/hash_benchmark_report.py
@@ -1229,10 +1229,20 @@ def dispatch_publish(args, stamp):
         full = _results_from_bundle(bundle_path)  # re-distilled from the bundle's raw (see B)
         ctx = full.get("context", {})
         label = _machine_label(ctx)
+        # We did the measurement before the extras were saved.
+        # if label == "AMD Ryzen 9 9950X 16-Core Processor · Linux · x86_64 · 10-core · clang-22 · 29b54ccd":
+        #    ctx["config"] = ["clang"]
+        #    ctx["copt"] = ["-march=znver5"]
         charts = dict(_render_charts(full, _bundle_stem(ctx), args.charts_dir, label))  # tag -> filename
         # `### {label}` heads the block; each section is its chart (if any)
         # immediately followed by its table, in layout order.
         parts = [f"### {label}", "", f"<!-- {label}; {_agg_label(ctx)} -->"]
+        extras = []
+        for extra_key in ["config", "copt", "host_copt"]:
+            if ctx.get(extra_key):
+                extras += [f"- **{extra_key}**: " + ", ".join([f"`{x}`" for x in ctx[extra_key]])]
+        if extras:
+            parts += ["", "#### Extra build configuration", ""] + extras
         for section in _sections(full):
             if section["tag"] in charts:
                 parts += ["", f"![mbo/hash {section['title']}, {label}]({rel}/{charts[section['tag']]})"]
diff --git a/mbo/mope/mope_main.cc b/mbo/mope/mope_main.cc
index e769e5a..bcce422 100644
--- a/mbo/mope/mope_main.cc
+++ b/mbo/mope/mope_main.cc
@@ -256,7 +256,7 @@ INI groups are used as sections. They can build ahierarchy:
 
 Example:
 
-```
+```text
 [person]
 id=0
 [person.contact]