FAQ
Frequently asked questions about QNSQY post-quantum data encryption, database migration, cold storage PQC, migration-as-a-service, and PQC readiness assessments.
General
Security
Practical Use
encrypt at the folder: qnsqy encrypt -i myfolder -o myfolder.qs. QNSQY packs the folder into an archive, encrypts it into one file and wipes the temporary archive; while it works, that plaintext archive sits briefly in the temporary folder. Decrypting restores the folder. A file is unpacked as a folder only when it was encrypted as one, and links or paths that would escape the target folder are refused.
qnsqy login. Your existing encrypted files will continue to work; the file format is identical across all tiers. Pro gives you ML-KEM-512/768/1024 + ML-DSA-44/65/87 and SLH-DSA, all unlimited with no metering. Business makes everything unlimited. Enterprise adds a signed SLA, dedicated engineering channel, quarterly 4-hour readiness consult, white-glove onboarding, and a named customer-success contact (an offline licence exists in the CNSA 2.0 edition, which is not released; HSM integration is planned; no dates).
Pricing & Licensing
Algorithms & Tiers
All tiers: AES-256-GCM, XChaCha20-Poly1305, Argon2id, BLAKE3, X25519 + Ed25519
Free: ML-KEM-512 + X25519 hybrid, ML-DSA-44
Pro: ML-KEM-512/768/1024, ML-DSA-44/65/87, SLH-DSA, ML-DSA+Ed25519 hybrid
Business: Everything in Pro plus FN-DSA-512/1024 (FIPS 206, not yet published; pre-standard Falcon implementation), FN-DSA+Ed25519 hybrid, HQC-128/192/256 + X25519, LMS (SP 800-208), compliance features, and organizational deployment
qnsqy timelock encrypt -i file --duration 30d
migrate command (Business), you can then re-encrypt these files with post-quantum encryption. Usage: qnsqy scan /path/to/data/ then qnsqy migrate /path/to/data/. This helps organizations systematically transition their encrypted data to quantum-safe protection.
qnsqy vault init, qnsqy vault add, qnsqy vault get, qnsqy vault list, qnsqy vault remove, qnsqy vault edit, qnsqy vault export, qnsqy vault import, qnsqy vault rekey. Clipboard auto-clears after 10 seconds.
qnsqy deniable create -o container then qnsqy deniable open -i container.
qnsqy threshold-encrypt -i file -m 3 -r key1.pub -r key2.pub -r key3.pub -r key4.pub -r key5.pub and qnsqy threshold-decrypt -i file.qs --key key1 --key key2 --key key3.
qnsqy keyfile generate -o mykey.qskf, qnsqy keyfile encrypt -i file --keyfile mykey.qskf, qnsqy keyfile decrypt -i file.qs --keyfile mykey.qskf. Note: keyfile encryption uses AES-256-GCM directly without KEM.
qnsqy hash -i file to compute a BLAKE3 hash, or qnsqy hash -i file -a sha3-256 for SHA3-256. Verify with qnsqy hash-verify -i file --hash <expected-hash>. Recursive directory hashing is supported with -r.
symmetric command (Pro+) provides a simplified encryption mode using AES-256-GCM or XChaCha20-Poly1305 directly with a password. Unlike the standard encrypt command, it doesn't use hybrid KEM or generate recipient keypairs. Just straightforward password-to-AES encryption. Usage: qnsqy symmetric -i file to encrypt, qnsqy symmetric -i file.qs -d to decrypt.
Organizations & Teams
For Developers
Troubleshooting
sudo or as the root user. Your license is tied to your normal user account and machine; running as root looks like a different user, so the saved subscription no longer matches and QNSQY falls back to Free. Run qnsqy as your normal user, never with sudo. If the tier is still wrong, run qnsqy login, make sure the machine can reach billing.quantumsequrity.com once, and let it revalidate online. After one successful online check the correct tier is cached for offline use.
npm install -g qnsqy --include=optional. This is by design: the wrapper stops with a clear message rather than leaving you a broken command.
gpgcheck=0, as our instructions did before 18 October 2026. Your installs were still protected: dnf verifies the repository metadata with our GPG key (repo_gpgcheck=1), and that signed metadata pins the exact SHA-256 of every package. Every QNSQY package is also signed with the same key, so turn on the per-package check once with sudo sed -i 's/^gpgcheck=0/gpgcheck=1/' /etc/yum.repos.d/qnsqy.repo. dnf then checks each package's own signature and no longer prints the message.
checksums.txt (sha256sum on Linux, certutil -hashfile <file> SHA256 or Get-FileHash on Windows). This shows the file matches the published list. (2) Post-quantum ML-DSA-87: qnsqy verify-release checksums.txt checksums.txt.sig proves the list itself was signed with our release key, which is embedded in every QNSQY binary. The current release also has (3) a Sigstore (cosign) signature on the website's list (quantumsequrity.com/downloads/checksums.txt), made with a short-lived certificate tied to our public GitHub build workflow and recorded in the public Rekor transparency log; cosign verify-blob checks it. Installing through the apt or dnf repo verifies signed metadata automatically. The exact commands are on the download page.
Pick one channel and stay on it. Check what you have at any time with qnsqy version.
npm: install npm install -g qnsqy, upgrade npm install -g qnsqy@latest, uninstall npm uninstall -g qnsqy.
apt (Debian / Ubuntu): after adding the QNSQY apt repo, sudo apt update && sudo apt install qnsqy; the same command upgrades; remove with sudo apt remove qnsqy.
dnf (Fedora / RHEL / AlmaLinux): after adding the repo, sudo dnf install qnsqy; upgrade sudo dnf upgrade qnsqy; remove sudo dnf remove qnsqy.
Windows: run the installer to set up or update, or replace the portable .exe with the newer one; uninstall via Settings > Apps (installer), or just delete the portable .exe.
qnsqy-setup-<version>.exe) sets QNSQY up system-wide, adds it to your PATH, and creates Start-menu entries; use it for a normal desktop install. The portable build (qnsqy-<version>-x86_64.exe) needs no installation: run it from any folder or a USB stick, which suits locked-down or air-gapped machines. On a fresh download Windows SmartScreen may say "Unknown Publisher"; the next answer explains why that is expected.
qnsqy --mcp to expose QNSQY's operations to any MCP-compatible agent over stdio (JSON-RPC). Point your agent's MCP client at that command and it can call tools such as encrypt, decrypt, sign, verify, and hash under the same tier rules as the CLI. From your own code: call the qnsqy command line; it can take the API key from the environment. A Developer API over HTTP is planned and not available yet. Both the MCP server and the command line run locally under your control; your keys and data are never sent to us.
This is expected: the Windows installer is not yet signed with a Windows code-signing (Authenticode) certificate, so Windows does not know the publisher. Check the download before you run it. QNSQY releases are signed with NIST FIPS 204 ML-DSA-87 post-quantum signatures: every release ships a SHA-256 checksums.txt manifest plus an ML-DSA-87 signature (checksums.txt.sig) over it, which, unlike Authenticode's RSA or ECDSA, is designed to resist quantum attacks. Windows does not yet natively verify post-quantum signatures, so SmartScreen labels the publisher as "Unknown".
A Microsoft Authenticode certificate costs money and takes weeks of vetting. We will add it as a convenience layer in a later release. The ML-DSA-87 check of the download is unaffected, and we chose to ship real post-quantum signatures today rather than wait on the legacy certificate path.
You can independently verify the binary two ways: (1) certutil -hashfile qnsqy.exe SHA256 or Get-FileHash qnsqy.exe matched against the SHA-256 on the download page, or (2) qnsqy verify-release checksums.txt checksums.txt.sig from any existing QNSQY install, which verifies the signed checksums manifest with the ML-DSA-87 key embedded in the binary (BLAKE3 fingerprint 50af23b47dca8d74; the same public key is published at quantumsequrity.com/keys/release-mldsa87.pub), then match your download's hash against the verified manifest. Once verified, click "More info" in the SmartScreen dialog, then "Run anyway". See If Windows warns you on the download page for the full step-by-step.
Post-quantum cryptography essentials
quantumsequrity; the full source is provided under NDA to evaluators and customers.
qnsqy shred does a 3-pass overwrite, which works well on traditional spinning disks. On SSDs with wear leveling, on copy-on-write filesystems (btrfs, ZFS), or on shingled-magnetic-recording disks, overwrite cannot reach every prior copy of the data. The honest recommendation for SSDs is full-disk encryption with secure-erase at decommission time. Use qnsqy shred as defense in depth, not as a sole data-destruction guarantee.
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