_{Part of Santh  ·  blog  ·  @SanthProject}

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keyhog scans source trees, git history, Docker images, GitHub/GitLab/Bitbucket repository collections, S3/GCS/Azure Blob buckets, and running systems for leaked credentials. 923 embedded detectors, decode-through (base64/hex/url/protobuf), confidence scoring, and SARIF output without hand-written runtime configuration. After verified-install calibration, keyhog scan . works with the canonical defaults; a source-built multi-backend binary first runs keyhog calibrate-autoroute.

Add it to your CI (one workflow file)

# .github/workflows/keyhog.yml
name: keyhog
on: [push, pull_request]
permissions: { contents: read, security-events: write }
jobs:
  scan:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: santhreal/keyhog/.github/actions/keyhog@v0.5.41
        with: { path: ., severity: high, format: sarif }

Release refs authenticate the complete binary and GPU literal bundle with minisign and SHA-256. Branch/SHA refs skip release lookup and build the checked-out source. With no explicit diagnostic backend, the Action visibly calibrates the runner before its default auto scan. The job summary reports measured duration; cost varies with the runner, cache, configuration, and repository. Findings auto-upload to GitHub code-scanning as SARIF. Adopt without breaking an existing tree by committing a baseline (keyhog scan --create-baseline .keyhog-baseline.json) so the action fails only on NEW secrets.

Release-tag behavior is fail-closed: exact release tags and the floating @v0 tag require complete, verifiable release assets. A missing or unverifiable asset never silently falls back to building different source; only branch/SHA refs build from source.

For lean CI source builds, disable default features and select the CI profile:

cargo install keyhog --no-default-features --features ci

This profile has no Hyperscan dependency, wgpu/Vulkan probe, or libstdc++ link. Native TLS still needs the platform's TLS build prerequisites. On Debian/Ubuntu, install libssl-dev and pkg-config. The profile retains the same embedded detector and ML/entropy/decode/multiline data paths. Use it in self-built CI images where binary size or container cold-start matters; the prebuilt installer above stays the default for a turnkey single-binary download.

GitLab CI, CircleCI, Drone, BuildKite, Jenkins, pre-commit, Husky, and lefthook recipes: integration recipes.

Protect local commits with keyhog hook install. The pre-commit guide owns staged-content, hook-replacement, bypass, and removal semantics. The CI guide owns the maintained workflows, baseline adoption, report retention, and exit handling.

How it works

KeyHog compiles its 923 detectors into a shared trigger/extraction plan, uses Hyperscan when that feature is present, decodes nested encodings before matching, and can apply explicit per-detector Bayesian Beta(α,β) confidence calibration. Hardware acceleration is an explicit backend selection layer; every selected backend must preserve the same detector ids and findings contract:

Layer / Backend	When	How
simdsieve prefilter	AVX-512 / AVX2 / NEON	Layer 1: skims every file for 12 high-value literal prefixes in one SIMD pass: AWS AKIA/ASIA, GitHub ghp_, OpenAI sk-proj-, Slack xoxb-/xoxp-, SendGrid SG., Square sq0csp-, and Stripe sk_live_/sk_test_/rk_live_/rk_test_
gpu-cuda-region-presence	executable CUDA peer + persisted calibration proof	VYRE literal-set region-presence through CUDA, followed by the shared CPU validation tail
gpu-wgpu-region-presence	executable WGPU peer + persisted calibration proof	VYRE literal-set region-presence through WGPU, followed by the shared CPU validation tail
simd-regex	Hyperscan compiled and live	parallel Hyperscan trigger scan plus full-regex extraction; portable builds do not expose this backend and report cpu-fallback instead
cpu-fallback	portable build or explicit CPU selection	Aho-Corasick prefix + Rust regex extraction

Autoroute

KeyHog autoroute measures every eligible backend and persists the fastest parity-checked choice for the exact binary, host, resolved policy, and workload class. It is not a hardware heuristic or fallback hierarchy: a missing or stale decision fails closed instead of silently choosing CPU, SIMD, or GPU.

Install performs the visible calibration. To recalibrate an installed binary, run keyhog calibrate-autoroute; inspect evidence with keyhog backend --autoroute. Explicit --backend values are diagnostic and benchmark overrides, not autoroute proof. Single-backend portable builds do not need a routing cache.

The complete parity contract, workload identity, GPU/Hyperscan behavior, daemon semantics, cache lifecycle, and troubleshooting matrix live in the autoroute reference.

Full documentation: santhreal.github.io/keyhog - install, first scan, output formats, detection internals, suppressions, verification, pre-commit + CI integration, CLI reference, autoroute, exit codes, env vars, and contributing. Source under docs/.

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Install

The signed Linux release binary needs the Hyperscan runtime and the installer needs minisign before it can verify anything. On Debian/Ubuntu, install both with sudo apt-get update && sudo apt-get install -y --no-install-recommends curl libhyperscan5 minisign; on macOS, run brew install minisign (the macOS release asset is portable and does not need Hyperscan).

# Linux / macOS, pinned and authenticated before execution
TAG=v0.5.41
BASE="https://github.com/santhreal/keyhog/releases/download/$TAG"
PUB='RWTPnJ/p6xVJ3TJIxr+ZVHMD/MTHWZhsdE38Go/oD3DYBoi4bePR55go'
curl -fSLO "$BASE/install.sh"
curl -fSLO "$BASE/install.sh.minisig"
minisign -Vm install.sh -P "$PUB"
KEYHOG_VERSION="$TAG" sh install.sh

# Windows uses the same signed, versioned flow. See the install guide.

# From source - Linux (install libhyperscan-dev + libssl-dev + pkg-config first)
git clone https://github.com/santhreal/keyhog.git
cd keyhog && cargo build --release -p keyhog

# From source - macOS Hyperscan path (Homebrew)
brew install vectorscan pkg-config
cargo install keyhog

# Portable scanner build - Windows or a host without Hyperscan/Vectorscan
# (no Hyperscan or GPU stack; native TLS build prerequisites still apply)
cargo install keyhog --no-default-features --features portable

The signed versioned installer is the recommended path. It authenticates the installer before execution, then selects and verifies the platform asset. See the install guide for PowerShell and checksum commands. Download and build time depend on the network, host, and cache. For a source build, note that the default features link Hyperscan/Vectorscan. Linux source builds also require libssl-dev and pkg-config for native TLS. Linux uses libhyperscan-dev; macOS source builds use Homebrew vectorscan. On Windows or a host without either library, build with --no-default-features --features portable for the pure Rust CPU scanner path with all portable scanner data features. Network source and verification features still use the platform native TLS dependency.

Works on Linux, macOS (Intel + Apple Silicon), and Windows. The verified installers calibrate multi-backend builds before enabling default automatic scans; a source build must run keyhog calibrate-autoroute first or use an explicit diagnostic backend.

The installer selects one asset per OS/architecture. The Linux x86_64 binary contains Hyperscan plus both VYRE CUDA and WGPU drivers; CUDA/NVRTC are loaded dynamically, so the same binary works on NVIDIA, other compatible GPUs, and CPU-only hosts without a build-time CUDA toolkit. Runtime probing reports which engines are usable, while persisted autoroute evidence selects the fastest measured-correct engine for each workload. macOS and Windows release assets are portable scanner builds without Hyperscan or GPU drivers. Each download is verified before it can replace your binary: the installer checks the release's minisign signature against keyhog's pinned public key and fails closed (refuses to install, touching nothing) if the signature is missing, wrong, or minisign itself is not installed - in which case it prints the one-line install command for your OS (sudo apt-get install minisign, brew install minisign, winget install -e --id jedisct1.minisign). It then SHA256-verifies the binary against the release-side checksum file. For an offline/air-gapped install without release verification, pass --insecure; the installer labels that trust downgrade visibly.

Pin a version with KEYHOG_VERSION=v0.5.41. Change the install dir with --install-dir=/usr/local/bin. Runtime backend policy belongs to keyhog scan --backend ..., [system].gpu, and autoroute calibration, not the installer asset name.

Three diagnostic modes ship with the same script:

sh install.sh --diagnose    # print host + binary state, change nothing
sh install.sh --repair      # re-download the platform asset for this host
sh install.sh --uninstall   # remove the binary + installer-owned shell wiring

For an interactive install (post-install wizard for PATH, shell completions, and a git pre-commit hook), reuse the authenticated versioned installer:

KEYHOG_VERSION="$TAG" sh install.sh

Daemon mode is Unix only. Everything else works identically on Windows.

Keep keyhog healthy and up to date

Once installed, keyhog maintains itself - the install script is only needed for the first install:

keyhog doctor                # health check: host probe + end-to-end scan self-test
keyhog backend --self-test --json # CI-readable GPU path health proof
keyhog update                # self-update to the latest release (verified download + atomic swap)
keyhog update --check        # is a newer release available? (exits 10 if yes, 0 if current)
keyhog repair                # reinstall a known-good binary if the self-test fails (--force to force)
keyhog uninstall             # remove the binary (dry run; pass --yes to actually delete)

keyhog doctor: host probe, install/PATH resolution, and an end-to-end scan self-test. On a usable physical-GPU host it additionally checks the production GPU scan path, GPU literal set, and GPU MoE shader against the CPU reference; those GPU checks are skipped on hosts without an eligible accelerator:

keyhog doctor reuses the scanner's own hardware probe and runs a real end-to-end self-test - it plants a synthetic secret and confirms the binary detects it - so it is the authoritative "will keyhog work here?" check (the installer runs it automatically after install). update and repair download the release binary and GPU-literal sidecar over HTTPS, verify both minisign signatures against keyhog's embedded public key, require both release-manifest SHA-256 checksums to match, and install them as one rollback-protected maintenance operation. A tampered, mismatched, or unsafe archive is refused. On a healthy host keyhog update is the one-command upgrade path. Implicit update/repair resolution ignores drafts and prereleases and requires the complete signed host bundle; pass --version <TAG> to select an exact published tag, including a prerelease. Network responses are bounded and timed out before any installed file is changed.

keyhog backend --self-test --json is the machine-readable GPU health gate for self-hosted runners. It exits 4 when the production GPU region-presence path fails and emits stable ok, status, exit_code, recommended_backend, and per-probe fields for CI routing. On a host without an eligible physical GPU it returns one gpu_adapter probe with status skip and exits 0; add --require-gpu to make absence a failed health gate (exit 4).

Quickstart

keyhog scan .                                          # scan a directory
keyhog scan --git-staged                               # pre-commit: only staged blobs
keyhog scan --git-diff main                            # files changed since base ref
keyhog scan --git-history .                            # added lines in commits reachable from HEAD
keyhog scan --docker-image registry/app:v1             # Docker image layers
keyhog scan --s3-bucket logs-prod --s3-prefix /        # S3 objects (--s3-endpoint for non-AWS)
keyhog scan --gcs-bucket logs-prod --gcs-prefix config/ # GCS objects (--gcs-endpoint for compatible APIs)
keyhog scan --azure-container-url "$AZURE_CONTAINER_URL" --azure-prefix config/
KEYHOG_GITHUB_TOKEN="$GH_PAT" keyhog scan --github-org acme # every repo in a GitHub org
KEYHOG_GITLAB_TOKEN="$GL_PAT" keyhog scan --gitlab-group acme # every project in a GitLab group
KEYHOG_BITBUCKET_USERNAME="$BB_USER" KEYHOG_BITBUCKET_TOKEN="$BB_APP_PASSWORD" \
  keyhog scan --bitbucket-workspace acme
keyhog scan-system --space 50G                         # walk every drive, every git history

Filter, format, gate:

keyhog scan . --severity high                  # info | client-safe | low | medium | high | critical
keyhog scan . --min-confidence 0.5             # raise the reporting confidence floor
keyhog scan . --format sarif -o keyhog.sarif   # GitHub code scanning
keyhog scan . --verify                         # live-verify against vendor APIs
keyhog scan . --create-baseline .keyhog-baseline.json
keyhog scan . --baseline .keyhog-baseline.json # only NEW findings vs snapshot
keyhog scan . --fast                           # pre-commit speed (no entropy/ML/decode recursion)
keyhog scan . --deep                           # highest-recall built-in preset
keyhog scan . --incremental                    # BLAKE3 Merkle skip → 10-100× CI loop

One scan, every CI/SIEM dialect: text · json · json-envelope · jsonl · jsonl-envelope · sarif · csv · html · junit · github-annotations · gitlab-sast, all from the same engine:

Exit codes: 0 clean, 1 findings above the severity floor, 2 user error (bad path, bad config, unsupported flag), 3 system error or detector-corpus audit failure, 4 backend --self-test failed, 10 live credentials found (requires --verify), 11 scanner panic (thread panicked mid-scan), 12 required GPU unavailable, 13 requested source failed or input coverage was incomplete. Matches keyhog --help.

What it catches

923 embedded detectors with checksum / companion validation:

• Cloud providers: AWS (access key + secret + STS verification), Azure (subscription key, storage account key, SAS), GCP (service account, API key), Cloudflare, Heroku, Vercel, Supabase.
• Payment processors: Stripe, Braintree, Razorpay, Paddle, Plaid, Square, and PayPal, with detector-owned checks and optional or required companions. A Razorpay key secret requires its nearby key ID.
• Source forges: GitHub PATs (with CRC32 checksum), GitLab tokens, Bitbucket app passwords, npm tokens (with checksum), Gitea / Forgejo / Codeberg.
• Auth / SSO: Okta, Auth0, Clerk, JumpCloud, Kinde.
• Comms: Slack, Discord, Twilio, SendGrid, Postmark, Mailgun, Resend, Loops.
• AI / ML: OpenAI (sk-/sk-proj-), Anthropic, Google AI Studio, Cohere, Mistral, HuggingFace, Replicate. HuggingFace organization credentials include both the current hf_ form and legacy api_org_ tokens.
• Password managers: 1Password account secret keys (A3- followed by five or six segmented uppercase alpha-numeric components).
• Databases: Postgres connection strings, MongoDB Atlas, Supabase service-role, PlanetScale, Neon, Turso, MySQL, Redis URLs.
• Generic + entropy discovery: API_KEY=<high-entropy-blob> catches credentials with no named detector, gated by per-context entropy thresholds + ML scoring.
• Cryptographic material: RSA / EC / SSH private keys, PGP private blocks, JWT signing secrets.

Each detector ships as a TOML file (data, not code): service metadata, regex patterns, keywords, companion fields, verification handler. Adding a new detector is 5-10 lines of TOML; the contributor guide walks through it.

keyhog explain <id> dumps any detector's full spec: patterns, keywords, verification endpoint, plus a service-keyed rotation and step-by-step remediation guide, so a finding is never a black box:

Browse detector authoring and inspection in the detector reference, or query the installed corpus with keyhog detectors --search <term> --verbose.

Why higher recall, fewer false positives

• Decode-through scanning. Kubernetes Secret manifests, JWT payloads, base64-wrapped envs, helm values, and docker-config auth: blobs. The structured preprocessor decodes them in place and feeds every downstream detector the plaintext, so detectors don't each need to re-implement decoding. Decode-enabled scans also recover recognized, side-effect-free JavaScript byte-array XOR and AES-256-CBC expressions when all recovery material is embedded, including strict CryptoJS/OpenSSL salted passphrase wrappers. KeyHog never executes the source.
• Multiline reassembly. "sk-proj-" + \ continuation in JavaScript, YAML multi-line strings, Makefile backslash-continuation, Helm / Jinja templated outputs, all reassembled before regex matching.
• Companion validation. Required companions gate high-noise detectors. A Twilio API key without its API secret is skipped. Optional companions enrich confidence or verification. AWS access-key detection does not require its secret, but the secret is needed for live verification.
• Confidence scoring. Every finding carries a [0.0, 1.0] score derived from Shannon entropy, surrounding context, companion match, checksum (GitHub CRC32, npm, Slack), and a small ML classifier (~30k params). Default threshold 0.40 (the canonical ScanConfig::default() floor; same as the --min-confidence default and the [scan].min_confidence example below) filters low-quality matches without hiding real secrets.
• Bayesian per-detector calibration. keyhog calibrate --fp generic-api-key writes a Beta(α,β) posterior. Scans use it only when --calibration-cache or [system].calibration_cache points at that file, so confidence tuning is explicit and reproducible instead of depending on stray host cache state.

Performance

Measured head-to-head against Betterleaks, Kingfisher, TruffleHog, and Titus, scored identically by the reproducible harness in benchmarks/: the SecretBench containment rule, with the ground-truth manifest excluded from every scanner's scan tree so no tool is ever shown the answer key. The tables below are generated by make -C benchmarks report: do not edit them by hand.

Detection leaderboard

Corpus: mirror - 15000 fixtures, 3000 labeled positives. Every scanner scored identically (SecretBench overlap rule); the answer-key manifest is excluded from the scan tree.

Rank	Scanner	F1	Precision	Recall	Findings	Wall	Peak RSS
1	KeyHog	0.9258	0.9954	0.8653	2612	1.58s	1543 MB
2	TruffleHog	0.5265	1.0000	0.3573	1072	1.45s	322 MB
3	Kingfisher	0.4720	0.3912	0.5947	5241	3.81s	502 MB
4	Titus	0.4127	0.3318	0.5457	5159	4.13s	114 MB
5	Nosey Parker	0.4078	0.3414	0.5063	4532	0.82s	534 MB
6	Betterleaks	0.3585	0.2313	0.7967	10828	1.04s	210 MB

Speed & memory

Scanner	Config	Corpus	Wall	Throughput	Peak RSS
Nosey Parker	default-nocache-nodaemon-no-git-history	mirror	0.75s	3.1 MB/s	285 MB
Betterleaks	default-nocache-nodaemon-no-validate	mirror	0.77s	3.0 MB/s	192 MB
Nosey Parker	default-nocache-nodaemon-no-git-history	mirror	0.82s	2.8 MB/s	534 MB
Nosey Parker	default-nocache-nodaemon-no-git-history	creddata	0.92s	1056.3 MB/s	1743 MB
Betterleaks	default-nocache-nodaemon-no-validate	mirror	1.04s	2.2 MB/s	210 MB
KeyHog	simd-nocache-nodaemon-full	mirror	1.27s	1.8 MB/s	1137 MB
KeyHog	simd-nocache-nodaemon-full	mirror	1.32s	1.8 MB/s	1153 MB
KeyHog	simd-nocache-nodaemon-full	mirror	1.40s	1.7 MB/s	1745 MB
TruffleHog	default-nocache-nodaemon-no-verify	mirror	1.45s	1.6 MB/s	322 MB
KeyHog	simd-nocache-nodaemon-full	mirror	1.58s	1.5 MB/s	1543 MB
TruffleHog	default-nocache-nodaemon-no-verify	mirror	1.73s	1.3 MB/s	308 MB
Titus	default-nocache-nodaemon-no-validate	mirror	2.53s	0.9 MB/s	117 MB
Betterleaks	default-nocache-nodaemon-no-validate	creddata	2.83s	342.8 MB/s	252 MB
Betterleaks	default-nocache-nodaemon-no-validate	creddata	3.07s	316.5 MB/s	261 MB
Titus	default-nocache-nodaemon-no-validate	creddata	3.16s	307.6 MB/s	2024 MB
KeyHog	simd-nocache-nodaemon-full	creddata	3.31s	293.8 MB/s	1887 MB
KeyHog	cpu-nocache-nodaemon-full	creddata	3.45s	281.7 MB/s	1821 MB
KeyHog	auto-nocache-nodaemon-full	creddata	3.52s	275.9 MB/s	1850 MB
Kingfisher	default-nocache-nodaemon-low-no-validate	mirror	3.81s	0.6 MB/s	502 MB
KeyHog	simd-nocache-nodaemon-full	creddata	3.91s	248.5 MB/s	1741 MB
KeyHog	simd-nocache-nodaemon-full	creddata	3.99s	243.7 MB/s	1720 MB
KeyHog	simd-nocache-nodaemon-full	creddata	4.02s	241.7 MB/s	1962 MB
KeyHog	simd-nocache-nodaemon-full	creddata	4.05s	240.0 MB/s	1677 MB
Titus	default-nocache-nodaemon-no-validate	mirror	4.13s	0.6 MB/s	114 MB
Kingfisher	default-nocache-nodaemon-low-no-validate	mirror	4.88s	0.5 MB/s	421 MB
KeyHog	gpu-nocache-nodaemon-full	creddata	5.12s	189.7 MB/s	3562 MB
KeyHog	simd-nocache-nodaemon-full	creddata	5.44s	178.6 MB/s	1641 MB
Kingfisher	default-nocache-nodaemon-low-no-validate	creddata	7.36s	131.9 MB/s	728 MB
Kingfisher	default-nocache-nodaemon-low-no-validate	creddata	8.13s	119.4 MB/s	657 MB
TruffleHog	default-nocache-nodaemon-no-verify	creddata	19.98s	48.6 MB/s	644 MB

Per-category recall gaps (where a competitor still wins recall)

Category	KeyHog P/R/F1	KeyHog TP/FN	Best competitor P/R/F1	Recall gap
authentication-key	1.000 / 0.973 / 0.986	498/14	Betterleaks 0.893 / 0.977 / 0.933	+0.004
generic-high-entropy-string	1.000 / 0.348 / 0.516	63/118	Betterleaks 1.000 / 0.807 / 0.893	+0.459

Reproduce: make -C benchmarks bench runs every scanner on the 15k SecretBench-mirror corpus and writes benchmarks/results/<host>/; make -C benchmarks report regenerates the tables above and benchmarks/reports/. See benchmarks/README.md for the corpora (mirror, competitor home-turf, Samsung/CredData) and the backend/cache/daemon/OS/GPU matrix.

Daemon mode

The optional Unix daemon keeps a compiled scanner warm for repeated eligible stdin and single-file scans. It runs in the foreground and is never started implicitly.

keyhog daemon start
keyhog scan --stdin --daemon < .env
keyhog daemon status
keyhog daemon stop

Omitting --daemon means auto on Unix. Bare --daemon means on, which fails if the service cannot honor the request exactly. Directory, Git, remote, verification, baseline, and policy-changing scans stay in process. See the daemon workflow for eligibility, retry, identity, socket trust, shutdown, coverage, and exit semantics.

Watch mode is a separate foreground filesystem-event loop; it does not connect to the daemon socket or appear in keyhog daemon status. For IDEs:

keyhog watch ./src                     # inotify/FSEvents/RDCW

System-wide credential triage

sudo keyhog scan-system --space 50G                  # default 50 GiB ceiling
sudo keyhog scan-system --space 1T --include-network # also scan NFS / SMB
sudo keyhog scan-system --space 10G --no-git-history # skip historical blobs

Enumerates every mounted drive (skipping pseudo-FS like /proc, /sys, tmpfs, nsfs, fuse.snapfuse), auto-discovers every .git (worktrees + bare repos + submodules), and runs the full scan + git-history pipeline. Honors a hard --space <bytes> ceiling and exits 1 on findings. Built for incident-response triage, M&A inheritance audits, and quarterly developer-laptop sweeps.

Lockdown mode (security-critical embeddings)

For deployments where keyhog runs on the same machine that holds the secrets (e.g. paired with EnvSeal) and there is no trusted boundary between the scanner and the credentials it inspects:

keyhog scan . --lockdown

Enforces:

• mlockall(MCL_CURRENT|MCL_FUTURE) on Linux: credentials never page to swap.
• PR_SET_DUMPABLE = 0 (always on, even outside lockdown): disables core dumps, ptrace, /proc/<pid>/mem reads. macOS gets PT_DENY_ATTACH.
• setrlimit(RLIMIT_CORE, 0) on Linux: the kernel refuses to write any core file regardless of the system coredump_filter, so anonymous pages can never reach disk via the dump path.
• Refuses to run if ~/.cache/keyhog/* exists, refuses --incremental writes, refuses --verify, refuses --show-secrets, refuses --fast / --no-decode / --no-entropy / --no-ml / --no-unicode-norm / --no-default-excludes (each trades off detection completeness for speed; lockdown is for the highest-stakes runs where you want every gate engaged).

The always-on hardening (everything except mlock + cache refusal) is applied to every KeyHog invocation. Even without --lockdown, the KeyHog process cannot be core-dumped or traced through ptrace.

Library API

use keyhog_core::{Chunk, ChunkMetadata};
use keyhog_scanner::CompiledScanner;

// Built-in embedded detectors, parsed through the fail-closed loader.
let detectors = keyhog_core::load_embedded_detectors_or_fail()?;
let scanner = CompiledScanner::compile(detectors)?;

let findings = scanner.scan(&Chunk {
    data: "TOKEN=sk_live_EXAMPLE…".into(),
    metadata: ChunkMetadata::default(),
});

The no-backend library methods are deterministic portable CPU references; they do not consult host heuristics or the CLI's calibration cache. Use scan_with_backend or scan_coalesced_with_backend for an explicit Hyperscan/GPU engine. The keyhog CLI owns persisted fastest-correct autoroute. The explicit-backend library methods return infallible finding vectors, so the selected backend is a hard process contract: unavailable SIMD terminates with exit 3, and unavailable or failed GPU execution terminates with exit 12 instead of returning findings from another engine. Call warm_backend to probe startup eligibility; use the CLI as a subprocess when an embedder must contain runtime accelerator failure.

Mix shipped + custom detectors by concatenating before compile. The scanner is Send + Sync; share one across rayon workers. Streaming source helpers in keyhog-sources (file-system, git, stdin, Docker, S3, GCS, Azure Blob, GitHub org, GitLab group, Bitbucket workspace). Live verification in keyhog-verifier.

The library boundary is documented in the architecture guide and crate-level Rust docs.

Configuration

Per-repo defaults via .keyhog.toml:

[scan]
severity = "high"
min_confidence = 0.40          # canonical default; raise toward 0.85 for fewer FPs
exclude = ["**/test/fixtures/**", "vendor/"]
gpu_batch_input_limit = "512MB" # optional; otherwise VRAM-adaptive

[limits]
stdin_bytes = "10MB"
web_response_bytes = "10MB"
cloud_max_objects = 100000
git_total_bytes = "256MB"
hosted_git_pages = 1000
docker_tar_total_bytes = "8GB"

[detector.generic-api-key]
enabled = false                # accelerated slots use this same canonical id

[detector.twilio-api-key]
min_confidence = 0.6           # per-detector floor; overrides the global one

[lockdown]
require = true                 # refuse to run unless --lockdown is passed

[system]
autoroute_cache = "/home/alice/.cache/keyhog/autoroute.json"  # or "off"
calibration_cache = "/home/alice/.cache/keyhog/calibration.json"
batch_pipeline = false                                       # true only for diagnostics/calibration
gpu = "auto"                                                 # auto | off | required

[aws]
canary_accounts = []           # extra 12-digit canary issuer accounts
knockoff_accounts = []         # treated the same way: do not live-verify

[tuning]
fallback_hs = true             # scanner recall-route defaults; printed by config --effective
hs_prefilter_max_len = 4096
hs_shard_target = 320
decode_focus = true
confirmed_suffix_gate = true
no_candidate_gate = true
gpu_recall_floor = false
gpu_moe_timeout_ms = 30000

Precedence (rightmost wins): compiled defaults → .keyhog.toml (walked up from the scan path) → CLI flags. The canonical defaults live in ScanConfig::default() (crates/core/src/config.rs). Full reference: docs/src/reference/configuration.md.

keyhog config --effective <path> prints the exact resolved scan and report policy (without scanning), so the precedence chain is provable (here a CLI --min-confidence 0.6 overrides the compiled 0.40 default):

Suppress a known finding by credential hash, path glob, or detector id in .keyhogignore, with optional reason, expires, and approved_by governance metadata. See Suppressions for rule ordering, inline directives, and composable .keyhogignore.toml predicates.

# .keyhogignore - gitignore-style shorthand
*.log
node_modules/
9d6060e21ef8d5daec9cfe4a44b1b1bc9792246bfad28210edaaa1782a8a676a

# Explicit form with governance
hash:9f86d081…    ; reason="rotated 2026-04-25" ; expires=2026-07-01 ; approved_by="security@acme"
detector:demo-token
path:**/fixtures/*.env

Entries past expires fail allowlist load with an actionable error, forcing the approval to be renewed or removed before the scan can proceed.

Architecture

Contributor map: Architecture is the one-page guide to the whole repo: every top-level directory, the crate layering, and the bytes→finding pipeline with each stage pointing at the module that owns it. Start there to navigate the code.

crates/
  core/       Detector loading, finding types, reporting (text/JSON/SARIF), allowlists
  scanner/    Hardware routing, Hyperscan, GPU, decode-through, entropy, ML, multiline
  sources/    File system, git (staged/diff/history), stdin, Docker, S3, GCS, Azure Blob, GitHub/GitLab/Bitbucket, web
  verifier/   Live credential verification for detectors with an active `[detector.verify]` endpoint
  cli/        CLI binary, daemon, watch, baselines, calibrate, hook installer
detectors/    923 TOML files (data, not code)
docs/src/     Canonical mdBook documentation deployed to GitHub Pages
benchmarks/   Reproducible eval harness: corpus generators, scanner adapters, scorer, gate, README report generator
tools/        Contract generators (gen_contracts.py, gen_companion_contracts.py)

Two-phase coalesced scan:

1. Phase 1: shared trigger scan on raw bytes, parallel across all files via rayon. Hyperscan accelerates this phase when compiled; portable builds use the pure-Rust trigger path. Files with no trigger hit stop before extraction.
2. Phase 2: full extraction on hits only: regex capture groups, companion matching, checksum validation, entropy gating, ML confidence + explicit Bayesian damping when configured.

Result: extraction work is concentrated on trigger-positive data. Determinism is part of the contract: same input → same output, byte-exact, every time.

The full pipeline, routing ownership, and profiling entrypoints live in the architecture guide and backend reference.

Other useful subcommands

keyhog detectors --search aws --verbose      # list / inspect detectors
keyhog explain aws-access-key                # spec, regex, severity, rotation guide
keyhog diff before.json after.json           # NEW / REMOVED / UNCHANGED, removals unknown by default
keyhog calibrate --tp aws-access-key         # record a true positive
keyhog calibrate --fp generic-api-key        # record a false positive
keyhog calibrate --show                      # posterior-mean bar chart per detector
keyhog scan . --calibration-cache ~/.cache/keyhog/calibration.json
keyhog backend                               # detected hardware + routing matrix
keyhog completion zsh                        # shell completions (bash/zsh/fish/powershell/elvish)

Contributing

• New detector? Drop a TOML in detectors/, open a PR. The contributor guide (CONTRIBUTING.md) has the schema and a worked example.
• Bug / missed secret / false positive? File an issue with the redacted credential shape and detector id; each report becomes a permanent test fixture under tests/contracts/.
• Security issue in KeyHog itself? Don't open a public issue; use GitHub private vulnerability reporting. If that form is unavailable, email security@santh.dev; PGP is not required.

Changelog. Open issues.

Credits

KeyHog stands on prior secret-scanning work. Ideas borrowed from:

• TruffleHog: detector breadth and verification semantics
• Betterleaks: token-efficiency and false-positive suppression
• Titus: scanning ergonomics and severity calibration

Thanks to these projects and their contributors.

License

License: MIT OR Apache-2.0.

Terms: MIT and Apache-2.0. This dual license covers the code and detector TOMLs. Commercial use, embedding, forks, and hosted services are permitted under either license.

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Star history

If keyhog has saved you from leaking a credential, a star is the cheapest way to tell the next person it exists.