diff --git a/.claude/development.md b/.claude/development.md
new file mode 100644
index 0000000..886484a
--- /dev/null
+++ b/.claude/development.md
@@ -0,0 +1,47 @@
+# pgxntool Development Guidelines
+
+**THIS FILE IS FOR PGXNTOOL DEVELOPERS ONLY.**
+
+If you are an extension developer using pgxntool in your project, this file does not
+apply to you. See the top-level `CLAUDE.md` instead.
+
+## Critical: Work from pgxntool-test, Not Here
+
+**NEVER make changes to pgxntool directly from this repository.**
+
+pgxntool development must be done from a checkout of **pgxntool-test**, which contains
+the full test infrastructure. Working here directly means you cannot run tests, and
+any changes you commit cannot be validated before merging.
+
+**Correct workflow:**
+1. Clone or use an existing checkout of `pgxntool-test`
+2. Work in a worktree: both `pgxntool/` and `pgxntool-test/` will be siblings
+3. Make changes to `pgxntool/` from within that pgxntool-test context
+4. Run the test suite via `make test` in pgxntool-test before committing
+
+**See:** https://github.com/Postgres-Extensions/pgxntool-test for the full development
+workflow.
+
+---
+
+## Makefile Variable Assignment Rules
+
+**RULE: Do not use `:=` (simply expanded) unless you have a specific need for immediate evaluation.**
+
+Use `=` (recursively expanded) for standard variable assignments. Reserve `:=` for cases where the right-hand side must be evaluated exactly once at assignment time — for example, when assigning the result of a `$(call ...)` function that references the variable being set (which would cause infinite recursion with `=`).
+
+When a variable must also override command-line values, combine `override` with `:=` — but only where `override` is genuinely needed.
+
+## Debug Level Rules (lib.sh `debug` function)
+
+`debug LEVEL "msg"` prints when `DEBUG >= LEVEL`. LEVEL encodes how noisy/esoteric a message is — how far you'd crank `DEBUG` before you'd want to see it — **not** code nesting depth. A top-level line can warrant a high level if it's esoteric, and loop-body detail is usually high precisely because it's noisy. Judge by signal-to-noise.
+
+The tiers are anchors, not strict multiples of 10 — any value in range is fine, leaving room to fine-tune between existing calls without renumbering:
+
+- **10**: Critical errors, important warnings
+- **20**: Warnings, significant state changes
+- **30**: General debugging, function entry/exit, array operations
+- **40**: Verbose details, loop iterations
+- **50+**: Maximum verbosity (per-iteration innards)
+
+Note: The BATS test helper `debug` function (in `tests/lib/helpers.bash` in pgxntool-test) uses a separate 1–5 scale controlled by `$TESTDEBUG`. The two systems are independent.
diff --git a/CLAUDE.md b/CLAUDE.md
index e5d701a..75c9d16 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -18,10 +18,17 @@ may pick up the wrong run. `--commit SHA` targets the exact push and avoids it.
 
 ## Scope of This File
 
-The guidance in this CLAUDE.md applies to pgxntool's own source files and provides
-recommended best practices for projects using pgxntool. However, any agent working in
-an extension project should always defer to that project's own CLAUDE.md and
-instructions over anything stated here.
+**CLAUDE.md is for people USING pgxntool** — extension developers who have embedded
+pgxntool into their project via `git subtree`. It documents the build system, available
+commands, and how pgxntool works.
+
+**If you are making changes to pgxntool itself**, stop — you are in the wrong place.
+See `.claude/` in this directory for developer guidelines. More importantly, pgxntool
+development must be done from the **pgxntool-test** repository, not from here. See the
+`Development Workflow` section below.
+
+Any agent working in an extension project should always defer to that project's own
+CLAUDE.md and instructions over anything stated here.
 
 ## Git Commit Guidelines
 
diff --git a/HISTORY.asc b/HISTORY.asc
index 98ea2a3..66384e2 100644
--- a/HISTORY.asc
+++ b/HISTORY.asc
@@ -7,6 +7,15 @@ re-run `git init`, and the sync scripts aborted with "Not in a git repository."
 They now detect the repo with `git rev-parse --git-dir`, which works in both a
 normal clone and a worktree.
 
+== Fix `verify-results` checking stale results in `make results`
+`make results` ran `verify-results` before `make test`, so it checked stale
+`regression.diffs` from a prior run. Reordered so `verify-results` always
+checks the fresh results.
+
+== Fix `PGXNTOOL_ENABLE_TEST_BUILD`/`PGXNTOOL_ENABLE_TEST_INSTALL` ignoring command-line values
+Without `override`, the `pgxntool_validate_yesno` normalization was silently
+skipped when these variables were set on the command line.
+
 2.0.3
 -----
 == Fix pgxntool-sync remote, and make it runnable without make
diff --git a/base.mk b/base.mk
index fc9923e..a7ab93c 100644
--- a/base.mk
+++ b/base.mk
@@ -93,7 +93,9 @@ pgxntool_validate_yesno = $(strip \
 TEST_BUILD_SQL_FILES = $(wildcard $(TESTDIR)/build/*.sql)
 TEST_BUILD_FILES = $(TEST_BUILD_SQL_FILES)
 ifdef PGXNTOOL_ENABLE_TEST_BUILD
-  PGXNTOOL_ENABLE_TEST_BUILD := $(call pgxntool_validate_yesno,$(PGXNTOOL_ENABLE_TEST_BUILD),PGXNTOOL_ENABLE_TEST_BUILD)
+  # override needed so command-line values (make VAR=YES) are normalized, not silently ignored.
+  # := needed for immediate evaluation of the function call (avoids infinite recursion with =).
+  override PGXNTOOL_ENABLE_TEST_BUILD := $(call pgxntool_validate_yesno,$(PGXNTOOL_ENABLE_TEST_BUILD),PGXNTOOL_ENABLE_TEST_BUILD)
 else
   # Auto-detect: enable if test/build/ directory has SQL files
   ifneq ($(strip $(TEST_BUILD_FILES)),)
@@ -135,7 +137,9 @@ endif
 # Either approach would eliminate the ~10-line block repeated for each feature.
 TEST_INSTALL_SQL_FILES = $(wildcard $(TESTDIR)/install/*.sql)
 ifdef PGXNTOOL_ENABLE_TEST_INSTALL
-  PGXNTOOL_ENABLE_TEST_INSTALL := $(call pgxntool_validate_yesno,$(PGXNTOOL_ENABLE_TEST_INSTALL),PGXNTOOL_ENABLE_TEST_INSTALL)
+  # override needed so command-line values (make VAR=YES) are normalized, not silently ignored.
+  # := needed for immediate evaluation of the function call (avoids infinite recursion with =).
+  override PGXNTOOL_ENABLE_TEST_INSTALL := $(call pgxntool_validate_yesno,$(PGXNTOOL_ENABLE_TEST_INSTALL),PGXNTOOL_ENABLE_TEST_INSTALL)
 else
   # Auto-detect: enable if test/install/ directory has SQL files
   ifneq ($(strip $(TEST_INSTALL_SQL_FILES)),)
@@ -292,9 +296,14 @@ endif
 
 # make results: runs `make test` and copies all result files to expected.
 # DO NOT RUN THIS UNLESS YOU'RE CERTAIN ALL YOUR TESTS ARE PASSING!
+#
+# Dependency chain (verify-results: test) guarantees test completes before verify-results
+# checks regression.diffs, even under make -j. Listing both as independent prerequisites
+# of results would allow them to run concurrently, letting verify-results see stale state.
 .PHONY: results
 ifeq ($(PGXNTOOL_ENABLE_VERIFY_RESULTS),yes)
-results: verify-results test
+verify-results: test
+results: verify-results
 else
 results: test
 endif
diff --git a/lib.sh b/lib.sh
index 853dc84..3cbeb0e 100644
--- a/lib.sh
+++ b/lib.sh
@@ -60,12 +60,21 @@ array_not_empty() {
 # Debug function
 # Usage: debug LEVEL "message"
 # Outputs message to stderr if DEBUG >= LEVEL
-# Debug levels use multiples of 10 (10, 20, 30, 40, etc.) to allow for easy expansion
+#
+# LEVEL encodes how noisy/esoteric a message is -- roughly, how far you'd crank
+# DEBUG before you'd actually want to see it. Higher = noisier, more rarely
+# useful. This is signal-to-noise, NOT code nesting depth: a top-level line can
+# warrant a high level if it's esoteric, and loop-body detail is usually high
+# precisely because it's noisy.
+#
+# The tiers below are anchors, not strict multiples -- pick any value in range
+# to fine-tune between existing calls without renumbering:
 #   - 10: Critical errors, important warnings
 #   - 20: Warnings, significant state changes
 #   - 30: General debugging, function entry/exit, array operations
 #   - 40: Verbose details, loop iterations
-#   - 50+: Maximum verbosity
+#   - 50+: Maximum verbosity (per-iteration innards)
+#
 # Enable with: DEBUG=30 scriptname.sh
 debug() {
     local level=$1
diff --git a/pgtle.sh b/pgtle.sh
index 3b948e8..124ca84 100755
--- a/pgtle.sh
+++ b/pgtle.sh
@@ -156,7 +156,7 @@ MODULE_PATHNAME=""
 VERSION_FILES=()
 UPGRADE_FILES=()
 
-debug 1 "Global arrays initialized: VERSION_FILES=${#VERSION_FILES[@]}, UPGRADE_FILES=${#UPGRADE_FILES[@]}"
+debug 30 "Global arrays initialized: VERSION_FILES=${#VERSION_FILES[@]}, UPGRADE_FILES=${#UPGRADE_FILES[@]}"
 PGTLE_VERSION=""  # Empty = generate all
 GET_DIR_VERSION=""  # For --get-dir option
 
@@ -463,7 +463,15 @@ parse_control_file() {
             # Order matters: stripping quotes before removing comments leaves a rogue
             # trailing quote for values like 'version' # note. See issue #25.
             value="${value%%#*}"  # Remove trailing comments
-            value="${value%% }"   # Trim trailing whitespace
+            # Trim all trailing whitespace (spaces and tabs). The prior %% pattern with
+            # a literal space only removed one character; multiple spaces or a tab before
+            # the comment (e.g., 'value'   # note or 'value'$'\t'# note) would leave
+            # stray whitespace that breaks the quote-strip below.
+            if [[ "$value" =~ ^(.*[^[:space:]])[[:space:]]*$ ]]; then
+                value="${BASH_REMATCH[1]}"
+            else
+                value=""
+            fi
 
             # Strip quotes if present (both single and double)
             value="${value#\'}"
@@ -513,21 +521,21 @@ parse_control_file() {
 
 discover_sql_files() {
     echo "Discovering SQL files for extension: $EXTENSION" >&2
-    debug 2 "discover_sql_files: Starting discovery for extension: $EXTENSION"
+    debug 30 "discover_sql_files: Starting discovery for extension: $EXTENSION"
 
     # Ensure default_version file exists and has content if base file exists
     # This handles the case where make all hasn't generated it yet, or it exists but is empty
     local default_version_file="sql/${EXTENSION}--${DEFAULT_VERSION}.sql"
     local base_file="sql/${EXTENSION}.sql"
     if [ -f "$base_file" ] && ([ ! -f "$default_version_file" ] || [ ! -s "$default_version_file" ]); then
-        debug 3 "discover_sql_files: Creating default_version file from base file"
+        debug 40 "discover_sql_files: Creating default_version file from base file"
         cp "$base_file" "$default_version_file"
     fi
 
     # Find versioned files: sql/{ext}--{version}.sql
     # Use find to get proper null-delimited output, then filter out upgrade scripts
     VERSION_FILES=()  # Reset array
-    debug 3 "discover_sql_files: Reset VERSION_FILES array"
+    debug 40 "discover_sql_files: Reset VERSION_FILES array"
     while IFS= read -r -d '' file; do
         local basename=$(basename "$file" .sql)
         local dash_count=$(echo "$basename" | grep -o -- "--" | wc -l | tr -d '[:space:]')
@@ -545,7 +553,7 @@ discover_sql_files() {
     # Find upgrade scripts: sql/{ext}--{ver1}--{ver2}.sql
     # These have TWO occurrences of "--" in the filename
     UPGRADE_FILES=()  # Reset array
-    debug 3 "discover_sql_files: Reset UPGRADE_FILES array"
+    debug 40 "discover_sql_files: Reset UPGRADE_FILES array"
     while IFS= read -r -d '' file; do
         # Empty upgrade files are allowed (no-op upgrades)
         local basename=$(basename "$file" .sql)
@@ -566,15 +574,15 @@ discover_sql_files() {
         echo "    - $f" >&2
     done
 
-    debug 3 "discover_sql_files: Checking UPGRADE_FILES array, count=${#UPGRADE_FILES[@]}"
+    debug 40 "discover_sql_files: Checking UPGRADE_FILES array, count=${#UPGRADE_FILES[@]}"
     if array_not_empty "${#UPGRADE_FILES[@]}"; then
         echo "  Found ${#UPGRADE_FILES[@]} upgrade script(s):" >&2
-        debug 2 "discover_sql_files: Iterating over ${#UPGRADE_FILES[@]} upgrade files"
+        debug 30 "discover_sql_files: Iterating over ${#UPGRADE_FILES[@]} upgrade files"
         for f in "${UPGRADE_FILES[@]}"; do
             echo "    - $f" >&2
         done
     else
-        debug 2 "discover_sql_files: No upgrade files found"
+        debug 30 "discover_sql_files: No upgrade files found"
     fi
 }
 
@@ -752,7 +760,7 @@ generate_install_update_path() {
 
 generate_pgtle_sql() {
     local pgtle_version="$1"
-    debug 2 "generate_pgtle_sql: Starting for version $pgtle_version, extension $EXTENSION"
+    debug 30 "generate_pgtle_sql: Starting for version $pgtle_version, extension $EXTENSION"
     
     # Get capability using function (compatible with bash < 4.0)
     local capability=$(get_pgtle_capability "$pgtle_version")
@@ -761,9 +769,9 @@ generate_pgtle_sql() {
     
     # Ensure arrays are initialized (defensive programming)
     # Arrays should already be initialized at top level, but ensure they exist
-    debug 3 "generate_pgtle_sql: Checking array initialization"
-    debug 2 "generate_pgtle_sql: VERSION_FILES is ${VERSION_FILES+set}, count=${#VERSION_FILES[@]}"
-    debug 2 "generate_pgtle_sql: UPGRADE_FILES is ${UPGRADE_FILES+set}, count=${#UPGRADE_FILES[@]}"
+    debug 40 "generate_pgtle_sql: Checking array initialization"
+    debug 30 "generate_pgtle_sql: VERSION_FILES is ${VERSION_FILES+set}, count=${#VERSION_FILES[@]}"
+    debug 30 "generate_pgtle_sql: UPGRADE_FILES is ${UPGRADE_FILES+set}, count=${#UPGRADE_FILES[@]}"
     
     if [ -z "${VERSION_FILES+set}" ]; then
         echo "WARNING: VERSION_FILES not set, initializing" >&2
@@ -822,17 +830,17 @@ EOF
 
         # Install all upgrade paths
         local upgrade_count=${#UPGRADE_FILES[@]}
-        debug 3 "generate_pgtle_sql: upgrade_count=$upgrade_count"
+        debug 40 "generate_pgtle_sql: upgrade_count=$upgrade_count"
         if [ "$upgrade_count" -gt 0 ]; then
-            debug 2 "generate_pgtle_sql: Processing $upgrade_count upgrade path(s)"
+            debug 30 "generate_pgtle_sql: Processing $upgrade_count upgrade path(s)"
             local i=0
             while [ "$i" -lt "$upgrade_count" ]; do
-                debug 4 "generate_pgtle_sql: Processing upgrade file $i: ${UPGRADE_FILES[$i]}"
+                debug 50 "generate_pgtle_sql: Processing upgrade file $i: ${UPGRADE_FILES[$i]}"
                 generate_install_update_path "${UPGRADE_FILES[$i]}"
                 i=$((i + 1))
             done
         else
-            debug 2 "generate_pgtle_sql: No upgrade paths to process"
+            debug 30 "generate_pgtle_sql: No upgrade paths to process"
         fi
 
         cat <<EOF