diff --git a/wasm-port/AGENTS.md b/wasm-port/AGENTS.md
index d3efe0f..3ea1c96 100644
--- a/wasm-port/AGENTS.md
+++ b/wasm-port/AGENTS.md
@@ -19,6 +19,17 @@ Build a standalone CNC simulation system that:
 - does not drive real hardware;
 - preserves LinuxCNC software behavior as closely as practical.
 
+## Current Direction
+
+The migration target is the LinuxCNC source program itself, adapted to run as
+the standalone WASM simulation program. The project must not evolve a
+project-authored interpreter, planner, or CNC semantics layer now that the
+porting harness is running.
+
+Existing minimal runtime wrappers are migration probes only. They are allowed
+to expose, compile, and validate vendored LinuxCNC code, but they must not be
+expanded into a separate implementation of G-code behavior.
+
 ## Repository Boundaries
 
 1. `../linuxcnc/` is upstream and must be treated as read-only input for the
@@ -33,21 +44,24 @@ Build a standalone CNC simulation system that:
 ## Engineering Rules
 
 1. Reuse LinuxCNC source before reimplementing any CNC logic.
-2. Prefer wrappers, shims, and extraction scripts over invasive source edits.
-3. Preserve LinuxCNC semantics for:
+2. Do not add new project-authored CNC semantics when LinuxCNC source exists.
+   Replace temporary wrapper behavior with direct calls into vendored LinuxCNC
+   source, or with the narrowest shims needed to make those calls compile.
+3. Prefer wrappers, shims, and extraction scripts over invasive source edits.
+4. Preserve LinuxCNC semantics for:
    - G-code execution;
    - modal state;
    - parameter and variable behavior;
    - kinematics;
    - planner behavior;
    - machine and controller state visible to software.
-4. Replace only the native runtime edges:
+5. Replace only the native runtime edges:
    - file IO;
    - process model;
    - HAL runtime;
    - IPC;
    - GUI.
-5. Frontend code must be implemented with web technology, not migrated from
+6. Frontend code must be implemented with web technology, not migrated from
    native GUI code.
 
 ## Required Layout
diff --git a/wasm-port/SKILL.md b/wasm-port/SKILL.md
index aeee40f..f901971 100644
--- a/wasm-port/SKILL.md
+++ b/wasm-port/SKILL.md
@@ -38,6 +38,8 @@ Use this skill when the work involves any of the following:
 4. Native runtime dependencies are replaced at the edges, not copied whole.
 5. Machine state and controller-visible behavior are first-class compatibility
    targets, not optional nice-to-haves.
+6. Do not continue building a project-authored CNC program once the porting
+   harness runs; move behavior back to vendored LinuxCNC source functions.
 
 ## Source Reuse Priorities
 
@@ -96,6 +98,16 @@ Preferred order of work:
 6. Build the WASM export layer second.
 7. Build the JS SDK and HTML frontend last.
 
+Current migration emphasis:
+
+- Treat `linuxcnc_interp_minimal_runtime.cpp` as a temporary probe surface.
+- Retire hand-written `convert_g()` behavior by linking and calling vendored
+  LinuxCNC interpreter conversion code.
+- Add shims only for host/runtime edges that prevent vendored LinuxCNC source
+  from compiling.
+- Do not add new G-code behavior in JavaScript or in standalone C++ wrappers
+  except as a short-lived adapter around LinuxCNC code.
+
 ## Filesystem And Browser Guidance
 
 For browser use:
diff --git a/wasm-port/docs/porting-steps-standalone.md b/wasm-port/docs/porting-steps-standalone.md
index 4492279..d500f7b 100644
--- a/wasm-port/docs/porting-steps-standalone.md
+++ b/wasm-port/docs/porting-steps-standalone.md
@@ -371,7 +371,18 @@ Current verified progress:
   `interp_convert.cc::convert_straight()` and
   `rs274ngc_return.hh::NCE_CANNOT_DO_G1_WITH_ZERO_FEED_RATE`.
 - This proves the current extracted interpreter slice can parse and execute a
-  simple traverse and feed move through a standalone canonical event sink.
+  small fixture set through a standalone canonical event sink.
+- Important direction change: the minimal wrapper behavior is a migration
+  probe, not the program body. Do not expand it into a separate CNC
+  implementation. The next work must retire hand-written wrapper semantics and
+  move execution through vendored LinuxCNC interpreter source such as
+  `interp_convert.cc`, `interp_read.cc`, `interp_check.cc`, and
+  `interp_execute.cc`.
+- `tools/build_native_probes.sh` now includes
+  `linuxcnc_interp_convert_source_probe`, which directly compiles vendored
+  `interp_convert.cc`. The required `emcStatus` shim is limited to the native
+  status boundary used by `tag_arc()` for machine units; it is not a
+  project-authored CNC behavior implementation.
 
 ## Phase 4: Port INI Parsing Without Editing Upstream
 
@@ -670,9 +681,11 @@ Keep these documents under `wasm-port/docs/`:
 Continue expanding the standalone interpreter core from the verified minimal
 traverse path:
 
-1. replace the temporary minimal `convert_g()` implementation with thin
-   wrappers around more vendored interpreter conversion code,
-2. add `_x`/`_y`/`_z` named parameter fixture coverage and align it with
-   `#5420`/`#5421`/`#5422`,
-3. keep all source changes inside `wasm-port/` and leave `../linuxcnc/`
+1. replace the temporary minimal `convert_g()` implementation with calls into
+   vendored LinuxCNC interpreter conversion code.
+2. identify and shim the native runtime symbols blocking direct compilation of
+   `interp_convert.cc`, `interp_execute.cc`, and related interpreter files.
+3. keep fixture coverage as regression protection while deleting temporary
+   hand-written semantics.
+4. keep all source changes inside `wasm-port/` and leave `../linuxcnc/`
    read-only.
diff --git a/wasm-port/runtime/core/linuxcnc_wrap/linuxcnc_emc_status_probe.cpp b/wasm-port/runtime/core/linuxcnc_wrap/linuxcnc_emc_status_probe.cpp
new file mode 100644
index 0000000..3b56762
--- /dev/null
+++ b/wasm-port/runtime/core/linuxcnc_wrap/linuxcnc_emc_status_probe.cpp
@@ -0,0 +1,4 @@
+#include "nml_intf/emc.hh"
+
+static EMC_STAT standalone_emc_status;
+EMC_STAT *emcStatus = &standalone_emc_status;
diff --git a/wasm-port/runtime/core/shims/nml_intf/emc.hh b/wasm-port/runtime/core/shims/nml_intf/emc.hh
index bb770fa..78caaaf 100644
--- a/wasm-port/runtime/core/shims/nml_intf/emc.hh
+++ b/wasm-port/runtime/core/shims/nml_intf/emc.hh
@@ -1,7 +1,18 @@
 #pragma once
 
-// Minimal shim for the standalone INI parser build.
+// Minimal shim for standalone interpreter source probes.
 enum EmcJointType : int {
     EMC_LINEAR = 1,
     EMC_ANGULAR = 2,
 };
+
+class EMC_STAT {
+public:
+    struct Motion {
+        struct Traj {
+            double linearUnits = 1.0;
+        } traj;
+    } motion;
+};
+
+extern EMC_STAT *emcStatus;
diff --git a/wasm-port/tests/native/verify_native_probes.sh b/wasm-port/tests/native/verify_native_probes.sh
index 14a0e50..5f6ba40 100755
--- a/wasm-port/tests/native/verify_native_probes.sh
+++ b/wasm-port/tests/native/verify_native_probes.sh
@@ -35,6 +35,7 @@ check_exitcode linuxcnc_namedparam_harness
 check_exitcode linuxcnc_interp_minimal_harness
 check_exitcode linuxcnc_interp_minimal_harness.run
 check_exitcode linuxcnc_rs274_compile_probe
+check_exitcode linuxcnc_interp_convert_source_probe
 
 check_fixture_output() {
   local fixture="$1"
diff --git a/wasm-port/tools/build_native_probes.sh b/wasm-port/tools/build_native_probes.sh
index 4916915..c8d8ae1 100755
--- a/wasm-port/tools/build_native_probes.sh
+++ b/wasm-port/tools/build_native_probes.sh
@@ -31,7 +31,11 @@ rm -f \
   "$BUILD_DIR/linuxcnc_rs274_compile_probe.o" \
   "$BUILD_DIR/linuxcnc_rs274_compile_probe.exitcode" \
   "$BUILD_DIR/linuxcnc_rs274_compile_probe.stdout.log" \
-  "$BUILD_DIR/linuxcnc_rs274_compile_probe.stderr.log"
+  "$BUILD_DIR/linuxcnc_rs274_compile_probe.stderr.log" \
+  "$BUILD_DIR/linuxcnc_interp_convert_source_probe.o" \
+  "$BUILD_DIR/linuxcnc_interp_convert_source_probe.exitcode" \
+  "$BUILD_DIR/linuxcnc_interp_convert_source_probe.stdout.log" \
+  "$BUILD_DIR/linuxcnc_interp_convert_source_probe.stderr.log"
 
 g++ -std=c++20 -O2 \
   -D_GNU_SOURCE \
@@ -160,4 +164,26 @@ RS274_RC=$?
 set -e
 
 echo "$RS274_RC" > "$BUILD_DIR/linuxcnc_rs274_compile_probe.exitcode"
+
+set +e
+g++ -std=c++20 -O2 \
+  -D_GNU_SOURCE \
+  -DM_PI=3.14159265358979323846 \
+  -DOBJECT_FWD_DWA2002724_HPP \
+  -I"$SHIM_DIR" \
+  -I"$INCLUDE_DIR" \
+  -I"$VENDOR_DIR/src" \
+  -I"$VENDOR_DIR/src/rtapi" \
+  -I"$VENDOR_DIR/src/emc" \
+  -I"$VENDOR_DIR/src/emc/nml_intf" \
+  -I"$VENDOR_DIR/src/emc/motion" \
+  -I"$VENDOR_DIR/src/libnml/posemath" \
+  -c "$VENDOR_DIR/src/emc/rs274ngc/interp_convert.cc" \
+  -o "$BUILD_DIR/linuxcnc_interp_convert_source_probe.o" \
+  >"$BUILD_DIR/linuxcnc_interp_convert_source_probe.stdout.log" \
+  2>"$BUILD_DIR/linuxcnc_interp_convert_source_probe.stderr.log"
+CONVERT_SOURCE_RC=$?
+set -e
+
+echo "$CONVERT_SOURCE_RC" > "$BUILD_DIR/linuxcnc_interp_convert_source_probe.exitcode"
 echo "native probes complete"