diff --git a/stage0/.claude/skills/port-astgen/SKILL.md b/stage0/.claude/skills/port-astgen/SKILL.md
index 6f50420235..e3c782f1ce 100644
--- a/stage0/.claude/skills/port-astgen/SKILL.md
+++ b/stage0/.claude/skills/port-astgen/SKILL.md
@@ -18,17 +18,18 @@ edit `astgen.c`. The worker handles all of that.
 1. **NEVER stop early.** Do not pause to ask the user if you should continue.
    Do not summarize remaining work and wait. Keep looping until every test is
    enabled and passing.
-2. **ALWAYS run `zig build all-zig0 -Dvalgrind |& grep -v Warning | head -20`
-   yourself before committing.** Never trust the worker's claim that tests pass
-   — verify it. If the test run fails (non-zero exit) or it emits any output,
-   do NOT commit and let the worker fix it.
+2. **ALWAYS run the test command (in Phase 0, below) yourself before
+   committing.** Never trust the worker's claim that tests pass — verify it. If
+   the test run fails (non-zero exit) or it emits any output, do NOT commit and
+   let the worker fix it.
 
 ## Phase 0: Check for leftovers
 
 Before enabling anything new, run the existing tests:
 
 ```sh
-zig build test-zig0 -Dzig0-cc=tcc 2>&1 | head -20
+cd ~/code/zig
+./zig3 build test-zig0 -Dzig0-cc=tcc 2>&1 | head -20
 ```
 
 If tests **FAIL**: dispatch a worker (Step 4 below) with context
@@ -75,7 +76,7 @@ line to enable the test.
 
 Run:
 ```sh
-zig build test-zig0 -Dzig0-cc=tcc 2>&1 | head -10
+./zig3 build test-zig0 -Dzig0-cc=tcc 2>&1 | head -10
 ```
 Capture only the first ~10 lines. This tells you pass/fail at a glance
 without bloating your context. The worker will run the full test itself.
@@ -107,7 +108,7 @@ The worker returns a structured result. Extract:
 **You MUST verify before committing.** Run:
 
 ```sh
-zig build all-zig0 -Dvalgrind |& grep -v Warning | head -10 ; echo "EXIT: $?"
+./zig3 build all-zig0 -Dvalgrind |& grep -v Warning | head -10 ; echo "EXIT: $?"
 ```
 
 Check two things only: (1) EXIT is 0, (2) the ~10 lines of output
@@ -150,6 +151,6 @@ Go back to Step 1. **Never stop early** — continue until all
 
 When no disabled tests remain, run:
 
-    zig build all-zig0 -Dvalgrind
+    ./zig3 build all-zig0 -Dvalgrind
 
 If that fails, go back to Phase 0 (treat it as a leftover).
diff --git a/stage0/.claude/skills/port-astgen/worker-prompt.md b/stage0/.claude/skills/port-astgen/worker-prompt.md
index 3c0be81f22..479d63d791 100644
--- a/stage0/.claude/skills/port-astgen/worker-prompt.md
+++ b/stage0/.claude/skills/port-astgen/worker-prompt.md
@@ -26,7 +26,8 @@ return a result.
 ### Step 1: Run the full test
 
 ```sh
-zig build test-zig0 -Dzig0-cc=tcc 2>&1
+cd ~/code/zig
+./zig3 build test-zig0 -Dzig0-cc=tcc 2>&1
 ```
 
 Record the full output. If tests pass, skip to Step 5.
@@ -64,7 +65,7 @@ Apply the minimal mechanical change to `astgen.c` to match the upstream.
 Make ONE change at a time. After each change, run:
 
 ```sh
-zig build test-zig0 -Dzig0-cc=tcc 2>&1 | head -20
+./zig3 build test-zig0 -Dzig0-cc=tcc 2>&1 | head -20
 ```
 
 Check that no previously-passing tests broke. If your change causes
@@ -92,7 +93,7 @@ above the commented corpus entry).
      prefix back) and add a TODO comment above it describing the remaining diff.
 4. Final verification — this must exit 0 with no output:
 
-    zig build all-zig0 -Dvalgrind |& grep -v Warning | head -100
+    ./zig3 build all-zig0 -Dvalgrind |& grep -v Warning | head -100
 
 ### Step 6: Return result
 
@@ -126,6 +127,6 @@ COMMIT_MSG: <one-line descriptive message about what was ported/fixed>
   Zig one, which is the source of the bug. So standard "bug hunting" methods no
   longer apply — making implementations consistent is a much better approach
   in all ways.
-- From `zig build` commands, use *only* `zig build *-zig0`. Other `zig build`
+- From `./zig3 build` commands, use *only* `./zig3 build *-zig0`. Other `./zig3 build`
   commands may start building/testing zig itself, which takes ages and is
   wholly unnecessary.
diff --git a/zig3 b/zig3
new file mode 100755
index 0000000000..8b5b3dece0
--- /dev/null
+++ b/zig3
@@ -0,0 +1,5 @@
+#!/bin/sh
+
+export LD_LIBRARY_PATH=$(dirname $(ldd `which cppcheck` | awk '/libstdc\+\+\.so\.6/ {print $3}'))
+
+exec zig-out/bin/zig "$@"