docs: fix dead DECISIONS paths and freeze credibility gaps

DECISIONS.md

@@ -50,7 +50,7 @@ Entries that only restate a diff will be deleted.
 - Consequence: the port depends on libc math; Zig-only freestanding
   builds are out of scope.
 - Evidence: sampled glibc vs `std.math` on the same inputs (specials,
-  dense grids, powers of two). Counts in `dev/baseline-artifacts/16-libm-vs-stdmath.txt`:
+  dense grids, powers of two). Counts in `docs/evidence/baseline/16-libm-vs-stdmath.txt`:
   - sin 602117 samples, 0 differ
   - cos/tan/exp/log/log10/sqrt/ceil/floor/fabs: 0 differ on their samples
   - asin 26109 samples, 24441 differ (rate 0.936)
@@ -70,7 +70,7 @@ Entries that only restate a diff will be deleted.
   generic over a builder interface (ENCRUST-style encapsulated substitution,
   arXiv:2604.04527).
 - Choice: shared recursive-descent parser parameterized by a builder
-  (`parser.zig`). `NativeBuilder` builds `ast.Expr`. Prompt 3 adds a
+  (`parser.zig`). `NativeBuilder` builds `ast.Expr`. A later pass adds a
   C-layout builder in `c_abi.zig` without forking parse logic.
 - Consequence: builder interface must be rich enough for both layouts;
   some C-specific allocation tricks stay in the C builder.
@@ -92,7 +92,7 @@ Entries that only restate a diff will be deleted.
   `-Dfix-fac-overflow` rejects non-integer inputs with NaN (C truncates
   `fac(4.8)` to 24, which smoke expects). We do not use `*%` for default
   fac, because that would diverge from measured C.
-- Evidence: `dev/baseline-artifacts/14-fac-ncr-probe.txt`. smoke expects
+- Evidence: `docs/evidence/baseline/14-fac-ncr-probe.txt`. smoke expects
   `fac(4.8)==24`.
 
 ## D007  -  ncr/npr DoS surface is small under the overflow guard
@@ -107,12 +107,13 @@ Entries that only restate a diff will be deleted.
   another intentional divergence.
 - Evidence: `ncr(40,20)` 0.000046s; `ncr(1e9,100)` returns INF in 0.000001s;
   `ncr(UINT_MAX, 200000)` returns INF in 0.000001s
-  (`15c-ncr-dos.txt`).
+  (`docs/evidence/baseline/15c-ncr-dos.txt`).
 
 ## D008  -  Nesting bound 2048 (intentional divergence)
 
 - Constraint: C recurses without a depth limit and SIGSEGVs near depth
-  20144 on an 8 MiB stack (issue #136). The port must not inherit that crash.
+  20144 on WSL x86_64 with an 8 MiB stack (issue #136; host-dependent). The
+  port must not inherit that crash.
 - Options: raise stack; keep unbounded recursion; hard error at a bound;
   iterative parser with a heap stack.
 - Choice: hard error `error.NestingTooDeep` at depth 2048 (same number as
@@ -122,7 +123,8 @@ Entries that only restate a diff will be deleted.
 - Consequence: differential harnesses must treat deep nests as an expected
   divergence table entry, not a fuzz failure.
 - Evidence: unit test builds 1e6 nested parens and expects NestingTooDeep;
-  C crashes at 20144 without ASan.
+  C crashes at 20144 without ASan (WSL x86_64, 8 MiB stack; Darwin arm64
+  measured 23764 in `docs/findings.md`).
 
 ## D009  -  Two-layer public surface
 
@@ -136,8 +138,8 @@ Entries that only restate a diff will be deleted.
 
 ## D010  -  Export the accidental globals
 
-- Constraint: Prompt 1 `nm` showed `te_free_parameters` and `next_token` as
-  globally defined alongside the header API.
+- Constraint: early `nm` on the upstream object showed `te_free_parameters`
+  and `next_token` as globally defined alongside the header API.
 - Options: header API only; exact nm set.
 - Choice: exact nm set (all seven symbols).
 - Consequence: `State` is public as an extern struct so `next_token` can be

build.zig

@@ -183,5 +183,8 @@ pub fn build(b: *std.Build) void {
     // Also attach to the default test step so `zig build test --fuzz` sees Smith cases.
     test_step.dependOn(&run_harness_tests.step);
 
-    _ = b.step("demo", "Prompt 9: demo assets");
+    const demo_cmd = b.addSystemCommand(&.{ "bash", "docs/demo/regen-svgs.sh" });
+    demo_cmd.setCwd(b.path("."));
+    const demo_step = b.step("demo", "Regenerate docs/demo/*.svg from segment transcripts");
+    demo_step.dependOn(&demo_cmd.step);
 }

docs/demo-script.md

@@ -9,6 +9,30 @@ terminal captures of each segment are already committed under `docs/demo/`
 **Outstanding human action:** record the MP4 from this script and upload it
 with the submission form **before 2026-08-03 18:00 UTC**.
 
+## How to record (do this)
+
+1. Open a terminal at a large font (18–24 pt). Black or dark theme.
+2. Start screen recording (QuickTime on macOS: File → New Screen Recording,
+   select the terminal window only; or OBS; or `asciinema rec demo.cast`).
+3. `cd` into the repo root and run the commands in the shot list below, in
+   order. Pause 2 seconds on each success line the narration calls out.
+4. Stop recording under five minutes. Export MP4 (QuickTime: File → Export).
+5. Upload where the organizer form asks. Optionally link it from the README
+   after freeze if the form allows an external URL.
+
+If you use `asciinema`:
+
+```bash
+cd /path/to/tinyexpr.zig
+asciinema rec /tmp/tinyexpr-demo.cast
+# ... run the commands ...
+# Ctrl-D to stop
+# Convert if you have agg: agg /tmp/tinyexpr-demo.cast /tmp/tinyexpr-demo.gif
+```
+
+The SVG segments under `docs/demo/` are already committed for the README; the
+organizer still wants a live video of you running the suite.
+
 ## Assets already in the repo
 
 | Segment | SVG | Transcript |

docs/demo/regen-svgs.sh

@@ -0,0 +1,12 @@
+#!/usr/bin/env bash
+# Regenerate docs/demo/*.svg from docs/demo/segments/*.txt
+set -euo pipefail
+ROOT="$(cd "$(dirname "$0")/../.." && pwd)"
+cd "$ROOT"
+count=0
+for f in docs/demo/segments/*.txt; do
+  stem="$(basename "$f" .txt)"
+  python3 docs/demo/render_svg.py "$f" "docs/demo/${stem}.svg"
+  count=$((count + 1))
+done
+echo "demo SVGs regenerated: ${count}"

docs/evidence/baseline/14-fac-ncr-probe.txt

@@ -0,0 +1,52 @@
+=== fac(n) via te_interp ===
+n= 0 te=0x1p+0                   bits=3ff0000000000000 tgamma=0x1p+0                   same=1 inf=0 nan=0
+n= 1 te=0x1p+0                   bits=3ff0000000000000 tgamma=0x1p+0                   same=1 inf=0 nan=0
+n= 2 te=0x1p+1                   bits=4000000000000000 tgamma=0x1p+1                   same=1 inf=0 nan=0
+n= 3 te=0x1.8p+2                 bits=4018000000000000 tgamma=0x1.8p+2                 same=1 inf=0 nan=0
+n= 4 te=0x1.8p+4                 bits=4038000000000000 tgamma=0x1.8p+4                 same=1 inf=0 nan=0
+n= 5 te=0x1.ep+6                 bits=405e000000000000 tgamma=0x1.ep+6                 same=1 inf=0 nan=0
+n= 6 te=0x1.68p+9                bits=4086800000000000 tgamma=0x1.68p+9                same=1 inf=0 nan=0
+n= 7 te=0x1.3bp+12               bits=40b3b00000000000 tgamma=0x1.3bp+12               same=1 inf=0 nan=0
+n= 8 te=0x1.3bp+15               bits=40e3b00000000000 tgamma=0x1.3bp+15               same=1 inf=0 nan=0
+n= 9 te=0x1.626p+18              bits=4116260000000000 tgamma=0x1.626p+18              same=1 inf=0 nan=0
+n=10 te=0x1.baf8p+21             bits=414baf8000000000 tgamma=0x1.baf8p+21             same=1 inf=0 nan=0
+n=11 te=0x1.308a8p+25            bits=418308a800000000 tgamma=0x1.308a8p+25            same=1 inf=0 nan=0
+n=12 te=0x1.c8cfcp+28            bits=41bc8cfc00000000 tgamma=0x1.c8cfbffffffffp+28    same=0 inf=0 nan=0
+n=13 te=0x1.7328ccp+32           bits=41f7328cc0000000 tgamma=0x1.7328cc0000001p+32    same=0 inf=0 nan=0
+n=14 te=0x1.44c3b28p+36          bits=42344c3b28000000 tgamma=0x1.44c3b27ffffffp+36    same=0 inf=0 nan=0
+n=15 te=0x1.30777758p+40         bits=4273077775800000 tgamma=0x1.30777758p+40         same=1 inf=0 nan=0
+n=16 te=0x1.30777758p+44         bits=42b3077775800000 tgamma=0x1.3077775800001p+44    same=0 inf=0 nan=0
+n=17 te=0x1.437eeecd8p+48        bits=42f437eeecd80000 tgamma=0x1.437eeecd80002p+48    same=0 inf=0 nan=0
+n=18 te=0x1.6beecca73p+52        bits=4336beecca730000 tgamma=0x1.6beecca730001p+52    same=0 inf=0 nan=0
+n=19 te=0x1.b02b930689p+56       bits=437b02b930689000 tgamma=0x1.b02b930689001p+56    same=0 inf=0 nan=0
+n=20 te=0x1.0e1b3be415ap+61      bits=43c0e1b3be415a00 tgamma=0x1.0e1b3be415ap+61      same=1 inf=0 nan=0
+n=21 te=inf                      bits=7ff0000000000000 tgamma=0x1.6283be9b5c61fp+65    same=0 inf=1 nan=0
+n=22 te=inf                      bits=7ff0000000000000 tgamma=0x1.e77526159f06bp+69    same=0 inf=1 nan=0
+n=23 te=inf                      bits=7ff0000000000000 tgamma=0x1.5e5c335f8a4cep+74    same=0 inf=1 nan=0
+n=24 te=inf                      bits=7ff0000000000000 tgamma=0x1.06c52687a7b9ap+79    same=0 inf=1 nan=0
+n=25 te=inf                      bits=7ff0000000000000 tgamma=0x1.9a940c33f6123p+83    same=0 inf=1 nan=0
+n=26 te=inf                      bits=7ff0000000000000 tgamma=0x1.4d9849ea37eecp+88    same=0 inf=1 nan=0
+n=27 te=inf                      bits=7ff0000000000000 tgamma=0x1.19787e5d9f316p+93    same=0 inf=1 nan=0
+n=28 te=inf                      bits=7ff0000000000000 tgamma=0x1.ec92dd23d6967p+97    same=0 inf=1 nan=0
+n=29 te=inf                      bits=7ff0000000000000 tgamma=0x1.be6518687a785p+102   same=0 inf=1 nan=0
+n=30 te=inf                      bits=7ff0000000000000 tgamma=0x1.a27ec6e1f2d0dp+107   same=0 inf=1 nan=0
+=== fac fractional ===
+fac(20.9) => 0x1.0e1b3be415ap+61 bits=43c0e1b3be415a00 inf=0 nan=0
+fac(21.1) => inf bits=7ff0000000000000 inf=1 nan=0
+fac(-1) => nan bits=7ff8000000000000 inf=0 nan=1
+fac(1e20) => inf bits=7ff0000000000000 inf=1 nan=0
+=== ncr overflow-ish ===
+ncr(10,3) => 0x1.ep+6 bits=405e000000000000 inf=0 nan=0
+ncr(66,33) => inf bits=7ff0000000000000 inf=1 nan=0
+ncr(67,33) => inf bits=7ff0000000000000 inf=1 nan=0
+ncr(100,50) => inf bits=7ff0000000000000 inf=1 nan=0
+ncr(1000,2) => 0x1.e7cbp+18 bits=411e7cb000000000 inf=0 nan=0
+ncr(1e9,1) => 0x1.dcd65p+29 bits=41cdcd6500000000 inf=0 nan=0
+ncr(1e9,2) => 0x1.bc16d66d7926cp+58 bits=439bc16d66d7926c inf=0 nan=0
+ncr(-1,1) => nan bits=7ff8000000000000 inf=0 nan=1
+ncr(5,6) => nan bits=7ff8000000000000 inf=0 nan=1
+=== npr ===
+npr(10,3) => 0x1.68p+9 bits=4086800000000000 inf=0 nan=0
+npr(20,5) => 0x1.c638p+20 bits=413c638000000000 inf=0 nan=0
+npr(21,21) => inf bits=7ff0000000000000 inf=1 nan=0
+npr(100,2) => 0x1.356p+13 bits=40c3560000000000 inf=0 nan=0

docs/evidence/baseline/15c-ncr-dos.txt

@@ -0,0 +1,6 @@
+ncr(40,20)                   0x1.00c258d9ap+37 0.000046s
+ncr(60,30)                   0x1.a42902a5af0bfp+56 0.000002s
+ncr(1000000000,100)          inf 0.000001s
+ncr(1000000000,10000)        inf 0.000001s
+ncr(4000000000,100000)       inf 0.000001s
+ncr(4294967295,200000)       inf 0.000001s

docs/evidence/baseline/16-libm-vs-stdmath.txt

@@ -0,0 +1,20 @@
+fn total differ rate worst_abs_delta
+sin 602117 0 0.00000000 0.000000e+00
+cos 600022 0 0.00000000 0.000000e+00
+tan 600022 0 0.00000000 0.000000e+00
+asin 26109 24441 0.93611398 inf
+acos 26109 24494 0.93814394 inf
+atan 600022 30803 0.05133645 2.220446e-16
+sinh 26109 24 0.00091922 2.328306e-10
+cosh 26109 60 0.00229806 2.220446e-16
+tanh 26109 682 0.02612126 2.220446e-16
+exp 602117 0 0.00000000 0.000000e+00
+log 302116 0 0.00000000 0.000000e+00
+log10 300021 0 0.00000000 0.000000e+00
+sqrt 302116 0 0.00000000 0.000000e+00
+ceil 26109 0 0.00000000 0.000000e+00
+floor 26109 0 0.00000000 0.000000e+00
+fabs 26109 0 0.00000000 0.000000e+00
+pow 24831 8294 0.33401796 inf
+atan2 24831 3606 0.14522170 4.440892e-16
+fmod 24831 6000 0.24163344 7.500000e+00

docs/evidence/consumability/zig-fetch-save.txt

@@ -0,0 +1,12 @@
+# zig fetch --save of package tarball (measured 2026-08-02)
+# From scratch project /tmp/te-user-consumer after:
+#   tar -czf /tmp/tinyexpr-pkg.tar.gz build.zig build.zig.zon src LICENSE README.md
+#   zig fetch --save file:///tmp/tinyexpr-pkg.tar.gz
+#
+# Resulting build.zig.zon dependency entry:
+.tinyexpr = .{
+    .url = "file:///tmp/tinyexpr-pkg.tar.gz",
+    .hash = "tinyexpr-0.1.0-fv-tH2JQAQC8ICkMA05jq1R8UmuqAqglyWWub-G8lCKK",
+}
+# zig build run printed: external_fetch_ok value=10
+# See also zig-fetch-external-run.txt

docs/evidence/cross-compile.json

@@ -73,7 +73,7 @@
     "unit_tests": "pass",
     "full_suite": "not_run",
     "ran": true,
-    "run_notes": "zig build test -Dtarget=wasm32-wasi -fwasmtime passed; wasm32-wasi is a third independent execution environment for differential work (prompt 5 seam)",
+    "run_notes": "zig build test -Dtarget=wasm32-wasi -fwasmtime passed; wasm32-wasi is a third independent execution environment for differential work",
     "artifact": "libtinyexpr.a"
   }
 }

docs/evidence/scorecard.json

@@ -145,7 +145,7 @@
       "unit_tests": "pass",
       "full_suite": "not_run",
       "ran": true,
-      "run_notes": "zig build test -Dtarget=wasm32-wasi -fwasmtime passed; wasm32-wasi is a third independent execution environment for differential work (prompt 5 seam)",
+      "run_notes": "zig build test -Dtarget=wasm32-wasi -fwasmtime passed; wasm32-wasi is a third independent execution environment for differential work",
       "artifact": "libtinyexpr.a"
     }
   },

docs/evidence/self-audit.md

@@ -2,7 +2,8 @@
 
 Adversarial review before code freeze. Host: Kavyas-MacBook-Air-2.
 UTC start: 2026-08-02. Freeze deadline: 2026-08-03 18:00 UTC.
-Final commit SHA filled at tag time.
+Final commit SHA at tag `submission-v1`: `76dec4d0e7a8a47215416cc12af994a8f94ca98d`
+(re-pointed after credibility cleanup if a newer commit becomes the tag tip).
 
 Disposition legend: **fixed** / **ok** / **qualified** / **human-required**.
 

docs/journal.md

@@ -181,9 +181,10 @@ and is not run against C in-process.
 
 ## 2026-08-02 elmengo allocfault-fuzz-sanitizers
 
-Code freeze is 2026-08-03 18:00 UTC. Long differential fuzz started first
-(`bash scripts/run-fuzz.sh 14400 fuzz/log-long.txt long`) and continues in
-the background while the other campaigns run.
+Code freeze is 2026-08-03 18:00 UTC. A long differential fuzz was started
+(`bash scripts/run-fuzz.sh 14400 fuzz/log-long.txt long`) alongside the other
+campaigns; that host later crashed and `fuzz/log-long.txt` was never written.
+The certified 60s log remains the published duration evidence.
 
 Pillar 4 allocfault (`tools/allocfault`): one LD_PRELOAD interposer for C and
 Zig ABI. Corpus 107 inputs, **271** allocation ordinals tested, **0** crashes
@@ -225,9 +226,10 @@ Regenerated `docs/evidence/scorecard.json` after fixing fragment routing so
 `buglead-*` and `sanitizers` land under real keys instead of polluting the
 root. Coverage / enumeration / fuzz / alloc_fault / bugleads / sanitizers are
 `measured`. `docs/evidence/hash-verify.txt` rewritten; `upstream_hash_ok` is
-true. Long differential fuzz (`scripts/run-fuzz.sh 14400`) is still running
-with progress dumps under `.local/fuzz/progress-long.json`; `fuzz/log-long.txt`
-will be committed when that campaign ends. Do not invent a total.
+true. Long differential fuzz (`scripts/run-fuzz.sh 14400`) was started toward
+`fuzz/log-long.txt` and died with a WSL host crash; that artifact was never
+committed. The certified 60s run in `fuzz/log.txt` stands. Do not invent a
+long-run total.
 
 ## 2026-08-02 Kavyas-MacBook-Air-2 independent-reproduction
 

fuzz/README.md

@@ -30,16 +30,20 @@ Artifacts:
 - `corpus-seed/`: small tracked seed inputs.
 - `logs/`: gitignored runtime logs from `scripts/run-logged.sh`.
 
-## Differential fuzz (Prompt 5)
+## Differential fuzz
 
 ```bash
 bash scripts/run-fuzz.sh 60 fuzz/log.txt certified   # required 60s log
-bash scripts/run-fuzz.sh 14400 fuzz/log-long.txt long
+bash scripts/run-fuzz.sh 14400 fuzz/log-long.txt long  # optional long campaign
 bash scripts/run-metamorphic.sh
 bash scripts/run-libfuzzer.sh 30 fuzz/log-libfuzzer.txt
 zig build test -Doptimize=ReleaseSafe --fuzz   # Zig 0.16 built-in; not Debug
 ```
 
+The 60s certified log is `fuzz/log.txt` (0 divergences). A multi-hour
+`fuzz/log-long.txt` campaign was started on WSL and lost to a host crash;
+that artifact was never committed. The certified 60s run stands.
+
 `fuzz/harness.c` compares C (objcopy-renamed) vs Zig on result bits, error
 position, success/NULL, and structured near-valid inputs. `fuzz/log.txt` is
 the certified sixty-second run. Wall-clock is secondary; executions and

scripts/cross-compile.sh

@@ -107,7 +107,7 @@ for t in targets:
                 if test_triple != t:
                     note += f" (artifact target remains {t}; musl used for qemu without glibc runtimes)"
                 if t == "wasm32-wasi":
-                    note += "; wasm32-wasi is a third independent execution environment for differential work (prompt 5 seam)"
+                    note += "; wasm32-wasi is a third independent execution environment for differential work"
                 entry["run_notes"] = note
             else:
                 entry["unit_tests"] = "fail"

scripts/run-sanitizer-matrix.sh

@@ -1,5 +1,5 @@
 #!/usr/bin/env bash
-# Sanitizer / safety matrix (Prompt 5 Task 3). Writes docs/evidence/sanitizers.md
+# Sanitizer / safety matrix. Writes docs/evidence/sanitizers.md
 set -euo pipefail
 ROOT="$(cd "$(dirname "$0")/.." && pwd)"
 WORK="$ROOT/.local/sanitizers"

src/c_abi.zig

@@ -76,7 +76,7 @@ pub const State = extern struct {
 };
 
 comptime {
-    // Layout numbers were measured on x86_64 Linux (prompt 1). Other ABIs differ
+    // Layout numbers were measured on x86_64 Linux. Other ABIs differ
     // in pointer width; keep the struct definitions and skip the size lock there.
     if (@import("builtin").cpu.arch == .x86_64 and @import("builtin").os.tag == .linux) {
         if (@sizeOf(TeExpr) != 24 or @alignOf(TeExpr) != 8 or

src/parser.zig

@@ -1,6 +1,6 @@
 //! AST builder interface for the shared recursive-descent parser.
 //! NativeBuilder constructs tagged-union Expr nodes.
-//! CAbiBuilder (prompt 3.5) constructs te_expr-shaped trees.
+//! CAbiBuilder constructs te_expr-shaped trees.
 
 const std = @import("std");
 const ast = @import("ast.zig");