Native private CCS acceptance

Date: 2026-09-27. This receipt covers Zheng's native private proof backend and isolated CLI installation. It is feature-branch evidence, not a release candidate. Joy consumer acceptance is recorded separately in joy/audit/native-private/.

Source inputs

Every input above was clean when checked with git status --porcelain; revisions were read with git rev-parse HEAD. Sibling paths resolve to isolated worktrees. cargo metadata --format-version 1 --all-features --locked --offline at the final source revision reports no Trisha, Triton, TASM, Neptune, twenty-first or bfieldcodec_derive dependency. The new direct utility dependencies are getrandom and zeroize, locked respectively to 0.3.4 and 1.9.0. shasum -a 256 Cargo.lock at both source revisions gives 26168c02c3fe288833db961e832a4b80d3a84c71c73015391f87a25329e79163.

Environment observed with uname -m, sw_vers -productVersion, rustc --version and cargo --version: macOS arm64 26.4.1, rustc 1.95.0 (59807616e, Homebrew), Cargo 1.95.0 (f2d3ce0bd, Homebrew). These are local CPU results; this receipt contains no cross-platform execution or hardware acceleration measurement.

Validation

Commands below run from /Users/master/cyber/.worktrees/selfhost-0.4-native-private/zheng. The full check and acceptance suite were launched from clean source 6b5a8a85535efb8d2852736af738278a9bd92db7:

CARGO_TARGET_DIR=../target-zheng-check cargo check --workspace --all-targets --all-features --locked --offline
CARGO_TARGET_DIR=../target-zheng-release cargo test --workspace --all-features --release --locked --offline

Check passed with zero Rust warnings. The full suite passed 219 tests: 212 library tests, five execution-adversarial integration tests and two CLI tests, with zero failures or ignored tests. Both existing exhaustive legacy proof-wire mutation tests completed successfully. Local logs: /tmp/zheng-native-private-6b5a8a8-check.log and /tmp/zheng-native-private-6b5a8a8-tests.log.

The full suite includes eight new native backend tests. Their coverage is:

• Exact relation, statement and public-coordinate binding; fresh proof randomness.
• Invalid witnesses forged through an internal path that bypasses honest-prover validation, including the all-zero witness and mandatory constant coordinate.
• All three opening orientations and reconstruction of the corresponding views.
• Altered seeds, fields, commitments, dimensions, challenge values, truncated and trailing data, noncanonical fields and spliced repetitions.
• Linear and higher-degree CCS, and bounds checked before proof allocation.
• Bounded serde admission, including oversized and admitted-but-truncated hints.
• Exhaustive small-field comparison of the real two-view distribution against a witness-free simulator for two distinct square-root witnesses.

After the CLI-only correction at 50bbacd9837896e030b0c6649387d651de23c529:

CARGO_TARGET_DIR=../target-zheng cargo check -p zheng-cli --all-targets --locked --offline
CARGO_TARGET_DIR=../target-zheng cargo test -p zheng-cli --locked --offline

The check had zero Rust warnings; both CLI tests passed. Logs: /tmp/zheng-native-private-banner-check.log and /tmp/zheng-native-private-banner-tests.log. The native backend source is unchanged by this correction.

Committed CLI installation

Both committed source revisions were installed with the following command; the final installation uses 50bbacd9837896e030b0c6649387d651de23c529:

CARGO_TARGET_DIR=../target-zheng cargo install --path cli --locked --offline --root ../install-zheng-committed
../install-zheng-committed/bin/zheng --help
shasum -a 256 ../install-zheng-committed/bin/zheng
stat -f '%z' ../install-zheng-committed/bin/zheng

The final help command exited zero, displayed the native soft3 identity and marked the legacy CLI statement commands explicitly. The former blanket post-quantum and sub-millisecond claims are absent. Installed binary size: 781,440 bytes. SHA256: 6a23492e9e62c800892b619ed44ca717938f896aa0f4a08af45e82862d455d5a. Installation produced no Rust warnings; Cargo's isolated-prefix PATH reminder is an installation advisory. Logs and captured help: /tmp/zheng-native-private-50bbacd-install.log, /tmp/zheng-native-private-50bbacd-help.stdout and /tmp/zheng-native-private-50bbacd-help.stderr.

This CLI help smoke verifies installation and presentation. Native private proving is exercised by the library tests and Joy's consumer validation.

Assurance and limits

The implemented protocol is native private CCS, with exactly 219 repetitions. Its interactive error bound is (2/3)^219 < 2^-128. Noninteractive security additionally depends on Fiat–Shamir in the random-oracle model and the stated Hemera assumptions. Internal source review checked the arithmetic decomposition, transcript binding, wire admission and privacy model; this is not an independent production cryptographic audit.

Proof size and verifier work scale linearly with the admitted circuit, multiplied by the fixed repetition count. The 256 MiB native payload cap and circuit work bounds are executable admission limits, not benchmark throughput claims. Public program, input/output, circuit shape and reduction count remain visible. Hidden queries operate over authenticated public BBG tables. The inherited nox relation supports bounded static continuations and fixed branch output shapes. This receipt makes no succinctness, recursion, complete dynamic-VM coverage or 128-bit post-quantum claim. Owned view and seed buffers are cleared; caller-owned witness memory and all possible transient copies are outside that guarantee.

Delivery boundary

git ls-remote --symref origin HEAD refs/heads/release/0.4 initially reported default master at 44bd5bfec5cb6764123ea513a33a26c0877a488c and no release branch. release/0.4 was then created with a non-force push at accepted 80a8ca90208c3b49c4f2a8507d75fd17785fdfe3. A subsequent remote inspection confirmed that base and the unchanged default revision. Feature work belongs to feat/0.4-native-private-proofs. No default-branch merge, tag, release publication or package publication was performed by this delivery.