diff --git a/Makefile b/Makefile
index 772b6f47..39ade31e 100644
--- a/Makefile
+++ b/Makefile
@@ -420,7 +420,8 @@ MISC_WW_TARGETS = $(MISC_WW_TESTS:%=wwtest/%)
 # wide-rune round-trips, the c6 sep soak). Compiler/driver gates like
 # test/sep: they run under test-compiler.
 TOOL_WW_TESTS = test/tool/rejects_test.ww test/tool/driver_test.ww \
-	  test/tool/wwdump_test.ww test/tool/ffi_test.ww
+	  test/tool/wwdump_test.ww test/tool/ffi_test.ww \
+	  test/tool/attest_test.ww
 TOOL_WW_TARGETS = $(TOOL_WW_TESTS:%=wwtest/%)
 BOOTSTRAP_WRAPPER_SOURCES = test/wcc/950_selfcheck.c \
 	  test/wcc/991_w6a_ww.c \
diff --git a/test/tool/attest_test.ww b/test/tool/attest_test.ww
new file mode 100644
index 00000000..8b961cd8
--- /dev/null
+++ b/test/tool/attest_test.ww
@@ -0,0 +1,177 @@
+package attest_test;
+
+// The #6 @test DROP/KEEP/LINK emission property, driven by w6c /
+// w6c_ww DIRECTLY on the import-free test/wcc/data/attest_* fixtures.
+// Port of the retired native carrier test/wcc/911_attest_drop.c;
+// every assertion preserved.
+//
+// Direct-frontend is the only host that can compare -T and non-T on
+// the SAME input: `ww test` is always -T, `ww build` always non-T.
+// A @test fn is spliced out of a non-test build (harec-faithful,
+// ref/harec/src/check.c:3941 — checked but never emitted) and kept
+// under -T (the synth entry references it); the -T synth's `test.run`
+// callee stays an external CALL, so no driver resolution is needed.
+//
+// nondrop — attest_nondrop.ww compiled four ways (cs/ww x non-T/-T):
+// the plain fn's TEXT def is present in both modes; the three @test
+// TEXT defs are absent non-T and present under -T. The fixture layout
+// exercises the splice loop's unlink edges (head @test, surviving
+// plain fn, two consecutive @test). The presence rows run against the
+// cstage .s; the cs==ww byte-id in BOTH modes (rule 10) carries them
+// onto the wwstage .s by construction.
+//
+// undefbody — a @test body referencing an undefined symbol rejects in
+// non-T on both frontends: the body is type-checked BEFORE the splice
+// drops it (harec checks at :3913, drops at :3941).
+//
+// linkfail — non-test code CALLs a @test fn: non-T compile+assemble
+// succeed per stage triple, but the link MUST fail, and the link
+// stderr must name calldropped_test (non-vacuity: the failure is ON
+// the dropped @test symbol — a libwwrt path drift failing every link
+// would otherwise mask the property).
+
+import os;
+import os.exec;
+import strings;
+import testenv;
+import time;
+
+fn fail(label: str, why: str) void = {
+	let m: str = strings.concat("attest FAIL: ", label, " -- ", why,
+		"\n");
+	os.write(2, m.ptr, m.len: u64);
+	assert(false);
+};
+
+fn tmo() time.duration = {
+	return (60i64 * (time.second: i64)): time.duration;
+};
+
+fn runcode(dir: str, name: str, argv: []str) i32 = {
+	let co: testenv.commandout;
+	testenv.runcommand(dir, dir, name, argv, tmo(), &co);
+	if (co.termination != exec.termination.EXIT) { return -1; };
+	return co.code;
+};
+
+// column-0 anchored TEXT label; the '\n' prepend counts a
+// file-leading label too.
+fn hastext(s: str, sym: str) bool = {
+	return testenv.occurrences(strings.concat("\n", s),
+		strings.concat("\nTEXT ", sym, ",")) > 0;
+};
+
+@test fn nondrop() void = {
+	let td: str = testenv.fresh();
+	let fixture: str = strings.concat(testenv.repo(),
+		"/test/wcc/data/attest_nondrop.ww");
+	let comps: []str = ["w6c", "w6c", "w6c_ww", "w6c_ww"];
+	let testmode: []bool = [false, true, false, true];
+	let names: []str = ["cp", "ct", "wp", "wt"];
+	let asms: []str = ["", "", "", ""];
+	let j: i32 = 0;
+	for (j < 4) {
+		let outf: str = strings.concat(td, "/", names[j], ".s");
+		let av: []str = alloc([], 5u64)!;
+		append(av, testenv.driver(comps[j]));
+		if (testmode[j]) { append(av, "-T"); };
+		append(av, fixture);
+		append(av, "-o");
+		append(av, outf);
+		if (runcode(td, names[j], av) != 0) {
+			fail("nondrop", strings.concat(comps[j],
+				" nondrop compile failed"));
+		};
+		asms[j] = testenv.readfile(outf);
+		j += 1;
+	};
+
+	let syms: []str = ["data.nondrop_keep", "data.nondrop_test_a",
+		"data.nondrop_test_b", "data.nondrop_test_c",
+		"data.nondrop_keep", "data.nondrop_test_a",
+		"data.nondrop_test_b", "data.nondrop_test_c"];
+	let rowmode: []bool = [false, false, false, false,
+		true, true, true, true];
+	let present: []bool = [true, false, false, false,
+		true, true, true, true];
+	let whats: []str = ["plain fn kept non-T", "head @test dropped non-T",
+		"mid @test dropped non-T", "consecutive @test dropped non-T",
+		"plain fn kept under -T", "head @test kept under -T",
+		"mid @test kept under -T", "consecutive @test kept under -T"];
+	let i: i32 = 0;
+	for (i < syms.len) {
+		let s: str = asms[0];
+		if (rowmode[i]) { s = asms[1]; };
+		if (hastext(s, syms[i]) != present[i]) {
+			fail("nondrop", whats[i]);
+		};
+		i += 1;
+	};
+	if (!testenv.same(asms[0], asms[2])) {
+		fail("nondrop", "non-T @test-drop asm cs!=ww (rule 10)");
+	};
+	if (!testenv.same(asms[1], asms[3])) {
+		fail("nondrop", "-T @test-keep asm cs!=ww (rule 10)");
+	};
+	testenv.clean(td);
+};
+
+@test fn undefbody() void = {
+	let td: str = testenv.fresh();
+	let fixture: str = strings.concat(testenv.repo(),
+		"/test/wcc/data/attest_undefbody.ww");
+	let comps: []str = ["w6c", "w6c_ww"];
+	let c: i32 = 0;
+	for (c < 2) {
+		let av: []str = [testenv.driver(comps[c]), fixture, "-o",
+			"/dev/null"];
+		if (runcode(td, strings.concat("reject_", comps[c]), av) == 0) {
+			fail("undefbody", strings.concat(comps[c],
+				" (non-T) accepted an undefined symbol in a @test body"));
+		};
+		c += 1;
+	};
+	testenv.clean(td);
+};
+
+@test fn linkfail() void = {
+	let td: str = testenv.fresh();
+	let fixture: str = strings.concat(testenv.repo(),
+		"/test/wcc/data/attest_calldropped.ww");
+	let rt: str = strings.concat(testenv.repo(), "/out/lib/libwwrt.a");
+	let comps: []str = ["w6c", "w6c_ww"];
+	let asmts: []str = ["w6a", "w6a_ww"];
+	let linkts: []str = ["w6l", "w6l_ww"];
+	let s: i32 = 0;
+	for (s < 2) {
+		let asmf: str = strings.concat(td, "/lf.", comps[s], ".s");
+		let obj: str = strings.concat(td, "/lf.", comps[s], ".o");
+		let exe: str = strings.concat(td, "/lf.", comps[s], ".exe");
+		let cav: []str = [testenv.driver(comps[s]), fixture, "-o", asmf];
+		if (runcode(td, strings.concat("cc_", comps[s]), cav) != 0) {
+			fail("linkfail", strings.concat(comps[s],
+				" non-T calldropped compile failed"));
+		};
+		let aav: []str = [testenv.driver(asmts[s]), "-o", obj, asmf];
+		if (runcode(td, strings.concat("as_", asmts[s]), aav) != 0) {
+			fail("linkfail", strings.concat(asmts[s],
+				" calldropped assemble failed"));
+		};
+		let lo: testenv.commandout;
+		let lav: []str = [testenv.driver(linkts[s]), "-o", exe, obj, rt];
+		testenv.runcommand(td, td, strings.concat("ld_", linkts[s]), lav,
+			tmo(), &lo);
+		assert(lo.termination == exec.termination.EXIT);
+		if (lo.code == 0) {
+			fail("linkfail", strings.concat(linkts[s],
+				" linked calldropped (expected undefined-reference to ",
+				"the dropped @test sym)"));
+		};
+		if (!testenv.has(lo.stderr, "calldropped_test")) {
+			fail("linkfail", strings.concat(linkts[s],
+				" link failed but not on the dropped @test sym (masked)"));
+		};
+		s += 1;
+	};
+	testenv.clean(td);
+};
diff --git a/test/wcc/911_attest_drop.c b/test/wcc/911_attest_drop.c
deleted file mode 100644
index 64e1d021..00000000
--- a/test/wcc/911_attest_drop.c
+++ /dev/null
@@ -1,275 +0,0 @@
-/*
- * 911_attest_drop — the #6 @test DROP/KEEP/LINK emission property, driven
- * by `w6c` / `w6c_ww` DIRECTLY on import-free fixtures (task #83, M4 E2-C2b).
- *
- * The drop/keep behavior is a property of w6c's `-T` flag, NOT the build
- * model: a @test fn is spliced out of a non-test build (harec-faithful,
- * ref/harec/src/check.c:3941 — checked but never emitted) and kept under
- * -T (the synth entry references it). Direct-w6c is the only host that can
- * compare BOTH flags on the same input — `ww test` is always -T, `ww build`
- * always non-T. The fixtures are import-free so they feed w6c with no driver
- * resolution; the -T synth's `test.run` callee is left as an external CALL
- * (resolved at link, never needed for the emission grep), so no combined
- * unit is required. Re-hosts the 910/997 nondrop+undefbody+linkfail legs,
- * which die when those gates are deleted at the M4 flip.
- *
- * Legs:
- *   nondrop   — @test defs ABSENT non-T, PRESENT under -T (8 rows); the .s
- *               is cs==ww in BOTH modes (rule 10 — the drop is symmetric).
- *   undefbody — a @test body referencing an undef sym rejects in non-T:
- *               the body is type-checked BEFORE the splice drops it
- *               (harec checks at :3913, drops at :3941). Both stages.
- *   linkfail  — non-test code CALLs a @test fn: non-T drops the def but the
- *               CALL survives, so the link fails on the dangling symbol —
- *               harec-faithful loud failure, never a silent mis-link. Both
- *               stages.
- */
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-#include <sys/wait.h>
-
-static int
-runwait(const char *cmd)
-{
-	int rc = system(cmd);
-	if (rc == -1) return -1;
-	if (WIFEXITED(rc)) return WEXITSTATUS(rc);
-	return 1;
-}
-
-static const char *
-absbin(void)
-{
-	const char *b = getenv("BIN");
-	if (!b) b = "out/bin";
-	if (b[0] == '/') return b;
-	static char buf[2048];
-	char cwd[1024];
-	if (getcwd(cwd, sizeof cwd) == NULL) return NULL;
-	snprintf(buf, sizeof buf, "%s/%s", cwd, b);
-	return buf;
-}
-
-static int
-slurp(const char *path, char **outbuf, size_t *outlen)
-{
-	FILE *f = fopen(path, "rb");
-	if (!f) return -1;
-	fseek(f, 0, SEEK_END);
-	long n = ftell(f);
-	fseek(f, 0, SEEK_SET);
-	if (n < 0) { fclose(f); return -1; }
-	char *b = malloc((size_t)n + 1);
-	if (!b) { fclose(f); return -1; }
-	if (fread(b, 1, (size_t)n, f) != (size_t)n) { free(b); fclose(f); return -1; }
-	b[n] = '\0';
-	fclose(f);
-	*outbuf = b;
-	*outlen = (size_t)n;
-	return 0;
-}
-
-/* cmp_asm — w6c and w6c_ww asm for the same input must be byte-identical
- * (rule 10). Returns 0 on match. */
-static int
-cmp_asm(const char *csa, const char *wsa, const char *what)
-{
-	char *bc = NULL, *bw = NULL;
-	size_t nc = 0, nw = 0;
-	int rc = 0;
-	if (slurp(csa, &bc, &nc) < 0 || slurp(wsa, &bw, &nw) < 0) {
-		fprintf(stderr, "911 FAIL: slurp %s asm\n", what);
-		rc = 1;
-	} else if (nc != nw || memcmp(bc, bw, nc) != 0) {
-		fprintf(stderr, "911 FAIL: %s asm cs!=ww (cs %zu, ww %zu)\n",
-		    what, nc, nw);
-		rc = 1;
-	}
-	free(bc); free(bw);
-	return rc;
-}
-
-/*
- * #6: each row asserts whether a symbol's TEXT def appears in the asm emitted
- * for attest_nondrop.ww in a given mode. A @test fn is spliced out of a
- * non-test build (ref/harec/src/check.c:3941) and kept under -T (the synth
- * entry references it); a plain fn is always emitted. The fixture layout
- * exercises the splice loop's unlink edges: @test head (prev==nil), a
- * surviving plain fn, then two consecutive @test fns (unlink-after-unlink).
- */
-static const struct {
-	const char *sym;	/* TEXT label to grep for */
-	int testmode;		/* 1 => -T, 0 => plain build */
-	int present;		/* expected: 1 present, 0 absent */
-	const char *what;
-} nondrop_rows[] = {
-	{ "data.nondrop_keep",   0, 1, "plain fn kept non-T" },
-	{ "data.nondrop_test_a", 0, 0, "head @test dropped non-T" },
-	{ "data.nondrop_test_b", 0, 0, "mid @test dropped non-T" },
-	{ "data.nondrop_test_c", 0, 0, "consecutive @test dropped non-T" },
-	{ "data.nondrop_keep",   1, 1, "plain fn kept under -T" },
-	{ "data.nondrop_test_a", 1, 1, "head @test kept under -T" },
-	{ "data.nondrop_test_b", 1, 1, "mid @test kept under -T" },
-	{ "data.nondrop_test_c", 1, 1, "consecutive @test kept under -T" },
-};
-
-/* nondrop — compile attest_nondrop.ww four ways (cs/ww × non-T/-T) straight
- * to asm (no driver resolution), assert each row's TEXT def is present/absent
- * on the cstage output, then byte-compare cs vs ww in BOTH modes. The
- * present/absent rows run against the cstage .s alone; the cs==ww byte-id
- * carries the assertion onto the wwstage .s by construction. */
-static int
-nondrop(const char *bin)
-{
-	int pid = getpid();
-	char cp[256], ct[256], wp[256], wt[256], cmd[4096];
-	snprintf(cp, sizeof cp, "/tmp/at911nd_cp_%d.s", pid);
-	snprintf(ct, sizeof ct, "/tmp/at911nd_ct_%d.s", pid);
-	snprintf(wp, sizeof wp, "/tmp/at911nd_wp_%d.s", pid);
-	snprintf(wt, sizeof wt, "/tmp/at911nd_wt_%d.s", pid);
-
-	int rc = 0;
-	struct { const char *comp; const char *flag; const char *out; } jobs[] = {
-		{ "w6c",    "",    cp },
-		{ "w6c",    "-T ", ct },
-		{ "w6c_ww", "",    wp },
-		{ "w6c_ww", "-T ", wt },
-	};
-	for (size_t i = 0; i < sizeof jobs / sizeof jobs[0]; i++) {
-		snprintf(cmd, sizeof cmd,
-		    "%s/%s %stest/wcc/data/attest_nondrop.ww -o %s 2>/dev/null",
-		    bin, jobs[i].comp, jobs[i].flag, jobs[i].out);
-		if (runwait(cmd) != 0) {
-			fprintf(stderr, "911 FAIL: %s %snondrop compile\n",
-			    jobs[i].comp, jobs[i].flag);
-			rc = 1;
-		}
-	}
-
-	for (size_t i = 0; rc == 0 && i < sizeof nondrop_rows / sizeof nondrop_rows[0]; i++) {
-		const char *f = nondrop_rows[i].testmode ? ct : cp;
-		snprintf(cmd, sizeof cmd, "grep -q '^TEXT %s,' %s",
-		    nondrop_rows[i].sym, f);
-		int found = runwait(cmd) == 0;
-		if (found != nondrop_rows[i].present) {
-			fprintf(stderr, "911 FAIL: %s: %s %s (expected %s)\n",
-			    nondrop_rows[i].what, nondrop_rows[i].sym,
-			    found ? "present" : "absent",
-			    nondrop_rows[i].present ? "present" : "absent");
-			rc = 1;
-		}
-	}
-	if (rc == 0 && cmp_asm(cp, wp, "non-T @test-drop") != 0) rc = 1;
-	if (rc == 0 && cmp_asm(ct, wt, "-T @test-keep") != 0) rc = 1;
-
-	unlink(cp); unlink(ct); unlink(wp); unlink(wt);
-	return rc;
-}
-
-/* reject_plain — `<comp> <fixture>` (NON-T) must exit nonzero. Pins that a
- * @test body is type-checked before the #6 splice drops it: an undefined
- * symbol in the body is caught loud even though the fn never reaches codegen
- * (harec checks at :3913, drops at :3941). */
-static int
-reject_plain(const char *bin, const char *comp, const char *fixture,
-    const char *what)
-{
-	char cmd[4096];
-	snprintf(cmd, sizeof cmd, "%s/%s %s -o /dev/null 2>/dev/null",
-	    bin, comp, fixture);
-	if (runwait(cmd) == 0) {
-		fprintf(stderr, "911 FAIL: %s (non-T) accepted %s "
-		    "(expected reject)\n", comp, what);
-		return 1;
-	}
-	return 0;
-}
-
-/* linkfail — a plain fn calling a @test fn, built non-T: compile + assemble
- * succeed, but the link MUST fail (the dropped @test def leaves the call's
- * symbol dangling — harec-faithful loud failure, never a silent mis-link). */
-static int
-linkfail(const char *bin, const char *comp, const char *asmt, const char *linkt)
-{
-	int pid = getpid();
-	char asmf[256], obj[256], exe[256], lerr[256], rt[1024], cmd[4096];
-	snprintf(asmf, sizeof asmf, "/tmp/at911lf_%s_%d.s", comp, pid);
-	snprintf(obj,  sizeof obj,  "/tmp/at911lf_%s_%d.o", comp, pid);
-	snprintf(exe,  sizeof exe,  "/tmp/at911lf_%s_%d.exe", comp, pid);
-	snprintf(lerr, sizeof lerr, "/tmp/at911lf_%s_%d.err", comp, pid);
-	snprintf(rt,   sizeof rt,   "%s/../lib/libwwrt.a", bin);
-
-	int rc = 0;
-	snprintf(cmd, sizeof cmd,
-	    "%s/%s test/wcc/data/attest_calldropped.ww -o %s 2>/dev/null",
-	    bin, comp, asmf);
-	if (runwait(cmd) != 0) {
-		fprintf(stderr, "911 FAIL: %s non-T calldropped compile\n", comp);
-		rc = 1;
-	}
-	if (rc == 0) {
-		snprintf(cmd, sizeof cmd, "%s/%s -o %s %s 2>/dev/null",
-		    bin, asmt, obj, asmf);
-		if (runwait(cmd) != 0) {
-			fprintf(stderr, "911 FAIL: %s calldropped\n", asmt);
-			rc = 1;
-		}
-	}
-	if (rc == 0) {
-		snprintf(cmd, sizeof cmd, "%s/%s -o %s %s %s 2>%s",
-		    bin, linkt, exe, obj, rt, lerr);
-		if (runwait(cmd) == 0) {
-			fprintf(stderr, "911 FAIL: %s linked calldropped (expected "
-			    "undefined-reference to the dropped @test sym)\n", linkt);
-			rc = 1;
-		} else {
-			/* Non-vacuity: the link must fail ON the dropped @test
-			 * symbol, not for an unrelated reason — a libwwrt path drift
-			 * would otherwise mask the property by failing every link. */
-			snprintf(cmd, sizeof cmd, "grep -q calldropped_test %s", lerr);
-			if (runwait(cmd) != 0) {
-				fprintf(stderr, "911 FAIL: %s link failed but not on the "
-				    "dropped @test sym (masked)\n", linkt);
-				rc = 1;
-			}
-		}
-	}
-	unlink(asmf); unlink(obj); unlink(exe); unlink(lerr);
-	return rc;
-}
-
-/* Both stages: each tool triple compiles + assembles + links the same
- * import-free fixtures, so the drop/keep/link property is pinned on cstage
- * AND wwstage (the nondrop leg's cs==ww byte-id proves the .s identical;
- * the reject + link legs re-run the whole pipeline per stage). */
-static const struct {
-	const char *comp;
-	const char *asmt;
-	const char *linkt;
-} stages[] = {
-	{ "w6c",    "w6a",    "w6l"    },
-	{ "w6c_ww", "w6a_ww", "w6l_ww" },
-};
-
-int
-main(void)
-{
-	const char *bin = absbin();
-	if (!bin) { fprintf(stderr, "911 FAIL: getcwd\n"); return 1; }
-
-	if (nondrop(bin) != 0) return 1;
-	for (size_t i = 0; i < sizeof stages / sizeof stages[0]; i++) {
-		if (reject_plain(bin, stages[i].comp,
-		    "test/wcc/data/attest_undefbody.ww",
-		    "undefined symbol in @test body") != 0) return 1;
-		if (linkfail(bin, stages[i].comp, stages[i].asmt,
-		    stages[i].linkt) != 0) return 1;
-	}
-
-	printf("@test -T direct-w6c: non-T drop + -T keep (8 rows, cs==ww both "
-	    "modes) + checked-body reject + dangling-call link-fail, both "
-	    "stages (#6)\n");
-	return 0;
-}