diff --git a/wasm-port/docs/compatibility-validation.md b/wasm-port/docs/compatibility-validation.md
index dfce094..b61ff04 100644
--- a/wasm-port/docs/compatibility-validation.md
+++ b/wasm-port/docs/compatibility-validation.md
@@ -111,10 +111,10 @@ The current fixture expectations validate standalone behavior against both the
 vendored LinuxCNC source path and an upstream `rs274` side-by-side baseline for
 parser/conversion, offsets, feed-control, comment/logging, numbered-parameter,
 spindle-orient, file-open reset, file-finish, tool-reload, and O-word
-subroutine fixtures, plus the comparable canonical runtime edge calls.
-Fixtures that depend on standalone-only runtime adapters, HAL/INI/tool table
-setup, upstream `rs274` output gaps such as `WAIT`, or richer machine session
-state still need dedicated native LinuxCNC baselines.
+subroutine fixtures, plus threading/rigid tap and the comparable canonical
+runtime edge calls. Fixtures that depend on standalone-only runtime adapters,
+HAL/INI/tool table setup, upstream `rs274` output gaps such as `WAIT`, or
+richer machine session state still need dedicated native LinuxCNC baselines.
 
 The kinematics probes currently cover LinuxCNC identity/trivial kinematics,
 the switchable `5axiskins` XYZBCW bridge-mill model, and the TRT `xyzac`/`xyzbc`
diff --git a/wasm-port/docs/drift-report.md b/wasm-port/docs/drift-report.md
index 65aad41..bf0b2c5 100644
--- a/wasm-port/docs/drift-report.md
+++ b/wasm-port/docs/drift-report.md
@@ -69,9 +69,9 @@ semantic rewrites:
   path. The upstream `rs274` side-by-side baseline now covers simple motion,
   offsets, feed-control, comment/logging, numbered-parameter, spindle-orient,
   file-open reset, file-finish, tool-reload, and O-word subroutine fixtures;
-  it also covers comparable canonical runtime edge calls. Adapter-heavy
-  fixtures and upstream `rs274` output gaps such as `WAIT` still need dedicated
-  native LinuxCNC baselines.
+  it also covers threading/rigid tap and comparable canonical runtime edge
+  calls. Adapter-heavy fixtures and upstream `rs274` output gaps such as
+  `WAIT` still need dedicated native LinuxCNC baselines.
 
 ## Current Drift Conclusion
 
diff --git a/wasm-port/docs/porting-steps-standalone.md b/wasm-port/docs/porting-steps-standalone.md
index 4ca6593..53b1b28 100644
--- a/wasm-port/docs/porting-steps-standalone.md
+++ b/wasm-port/docs/porting-steps-standalone.md
@@ -507,12 +507,12 @@ Current verified progress:
   native LinuxCNC canonical output for simple motion, offsets, feed-control,
   comment/logging, numbered-parameter, spindle-orient, file-finish, and
   tool-reload fixtures. It now also includes file-open reset and O-word
-  subroutine fixture coverage, plus comparable canonical runtime edge calls.
-  Native output is filtered to the event classes each standalone fixture
-  explicitly expects, while upstream `rs274` output gaps such as `WAIT` remain
-  covered by the standalone harness rather than being treated as side-by-side
-  evidence. The comparison does not introduce a project-authored CNC semantics
-  oracle.
+  subroutine fixture coverage, threading/rigid tap coverage, plus comparable
+  canonical runtime edge calls. Native output is filtered to the event classes
+  each standalone fixture explicitly expects, while upstream `rs274` output
+  gaps such as `WAIT` remain covered by the standalone harness rather than
+  being treated as side-by-side evidence. The comparison does not introduce a
+  project-authored CNC semantics oracle.
 - `tests/fixtures/gcode_errors/g1_zero_feed.ngc` and
   `tests/fixtures/canon_errors/g1_zero_feed.expected` pin the negative
   `G1` zero-feed case. The source basis is LinuxCNC
diff --git a/wasm-port/tools/verify_native_linuxcnc_fixture_baseline.sh b/wasm-port/tools/verify_native_linuxcnc_fixture_baseline.sh
index 4fd8894..335a4e5 100755
--- a/wasm-port/tools/verify_native_linuxcnc_fixture_baseline.sh
+++ b/wasm-port/tools/verify_native_linuxcnc_fixture_baseline.sh
@@ -23,6 +23,7 @@ FIXTURES=(
   percent_file_finish
   position_params
   spindle_orient
+  threading_sync
   tool_reload
 )
 
@@ -224,6 +225,33 @@ normalize_standalone_events() {
         next
       }
 
+      if (line ~ /^START_SPEED_FEED_SYNCH /) {
+        split(line, fields, /[[:space:]]+/)
+        for (i in fields) {
+          split(fields[i], pair, "=")
+          values[pair[1]] = pair[2]
+        }
+        print "START_SPEED_FEED_SYNCH|" norm(values["feed_per_revolution"]) "|" values["velocity_mode"]
+        delete values
+        next
+      }
+
+      if (line == "STOP_SPEED_FEED_SYNCH") {
+        print line
+        next
+      }
+
+      if (line ~ /^RIGID_TAP /) {
+        split(line, fields, /[[:space:]]+/)
+        for (i in fields) {
+          split(fields[i], pair, "=")
+          values[pair[1]] = pair[2]
+        }
+        print "RIGID_TAP|" norm(values["x"]) "|" norm(values["y"]) "|" norm(values["z"])
+        delete values
+        next
+      }
+
       # Upstream rs274 does not emit saicanon WAIT for the M66 case.
       if (line ~ /^WAIT /) {
         next
@@ -476,6 +504,25 @@ normalize_upstream_rs274_output() {
         next
       }
 
+      if (line ~ /^START_SPEED_FEED_SYNC\(/) {
+        args = args_of(line)
+        split(args, values, ",")
+        print "START_SPEED_FEED_SYNCH|" norm(values[1]) "|" trim(values[2])
+        next
+      }
+
+      if (line == "STOP_SPEED_FEED_SYNCH()") {
+        print "STOP_SPEED_FEED_SYNCH"
+        next
+      }
+
+      if (line ~ /^RIGID_TAP\(/) {
+        args = args_of(line)
+        split(args, values, ",")
+        print "RIGID_TAP|" norm(values[1]) "|" norm(values[2]) "|" norm(values[3])
+        next
+      }
+
       if (line ~ /^SET_FEED_MODE\(/) {
         args = args_of(line)
         split(args, values, ",")