No cryptography background required to start. By the end of the glossary, you'll have the same vocabulary our engineering reviewers and buyer-side technical evaluators use.
How money became digital, how it's kept safe today, and why that's about to change.
People have traded goods for thousands of years — first directly, then through gold and silver, then paper notes backed by trust in governments. In 2009, someone using the name Satoshi Nakamoto proposed money that needed no bank or government at all: a shared ledger kept honest by math, open to anyone. That became Bitcoin.
Picture a giant public spreadsheet — the blockchain — visible to everyone, editable by no one. When you send Bitcoin, a new line is added. Ownership comes down to one thing: a private key, a secret number mathematically tied to your address. Hold the key, you control the coins. Ethereum, Solana, and the stablecoins (like USDT) that move on top of them all rest on the same private-key foundation.
Bitcoin's signatures run on elliptic-curve cryptography (ECC) — specifically a curve called secp256k1, paired with the ECDSA signature scheme (Taproot outputs use a related scheme called Schnorr). It's not "unbreakable," it just requires a classical computer roughly billions of years to guess a private key. Good enough for fifty years — until now.
A classical computer stores information as bits — 0 or 1. A quantum computer uses qubits, exploiting quantum physics to represent many states at once. That doesn't make it faster at everything. But for a narrow class of problems — including the ones ECC relies on — a large enough quantum computer solves them exponentially faster than any classical machine.
In 1994, Peter Shor published an algorithm proving a sufficiently powerful quantum computer — a Cryptographically Relevant Quantum Computer (CRQC) — could break the integer-factoring and discrete-logarithm problems behind RSA and ECC. The day that becomes real is called Q-Day. A separate result, Grover's Algorithm, only halves the effective strength of symmetric ciphers like AES — a smaller problem solved with longer keys. Credible estimates currently place Q-Day around 2029–2033; a Google Quantum AI resource estimate published in April 2026 compressed the timeline further, showing Shor's algorithm needs roughly 20× fewer qubits than previously thought.
Q-Day being years away doesn't mean the risk is years away. Adversaries can record encrypted data today — custody records, wallet logs, communications — and hold it until a quantum computer can break it. Anything that must stay confidential past Q-Day is already exposed if it isn't migrated now.
Institutional cryptographic migration — inventorying every key, certificate, and vendor dependency, then rolling out new algorithms without breaking production — takes five to seven years to do correctly. The cost of preparing early is bounded. The cost of being late is not. QHelm exists to make the "prepare early" side of that trade as close to zero-friction as software can make it.
The full technical vocabulary — standards, cryptographic construction, Bitcoin-specific terms, and the compliance layer built on top of them.
Post-Quantum Cryptography — cryptographic algorithms believed secure against both classical and quantum computers.
The U.S. National Institute of Standards and Technology — runs the multi-year public competition that decides which post-quantum algorithms become official government standards.
Federal Information Processing Standards — the NIST publication series that makes an algorithm an official U.S. government standard.
Standardizes ML-KEM, the Module-Lattice-Based Key Encapsulation Mechanism — the algorithm QHelm uses to wrap keys. Finalized August 2024.
Standardizes ML-DSA, the Module-Lattice-Based Digital Signature Algorithm — the post-quantum replacement for ECDSA/RSA signatures.
Standardizes SLH-DSA, a stateless hash-based signature scheme — a conservative, hash-based alternative signature standard finalized alongside ML-KEM and ML-DSA.
The NSA's Commercial National Security Algorithm Suite 2.0 — the mandated post-quantum algorithm set for U.S. national security systems, with deadlines beginning 2027 and full cutover by 2035.
Cryptographically Relevant Quantum Computer — a quantum computer powerful enough to actually break the public-key cryptography in production use today. The technical definition of "Q-Day arrived."
Key Encapsulation Mechanism — a way for two parties to establish a shared secret key using public-key cryptography, the building block ML-KEM is named for.
The algorithm behind FIPS 203, known as CRYSTALS-Kyber during the NIST competition. Security rests on Module Learning With Errors (MLWE) and Module Short Integer Solution (MSIS) — lattice problems, not factoring, which is why Shor's algorithm doesn't break it.
QHelm pairs ML-KEM with classical X25519 (elliptic-curve) key exchange. Defense in depth: if either the lattice math or the elliptic-curve math is ever broken, the other still holds the key. This is the recommended posture during the CNSA 2.0 transition period.
Key Encapsulation Mechanism + Data Encapsulation Mechanism — the standard pattern of using a KEM to establish a key, then a symmetric cipher (QHelm uses AES-256-GCM) to actually encrypt the data.
HMAC-based Key Derivation Function — derives the final AES wrapping key from the raw KEM shared secret. QHelm uses HKDF-SHA3-256 with domain separation so a wrap can't be replayed against the wrong account or tenant.
Indistinguishable under Chosen-Ciphertext Attack — the strong security definition ML-KEM is designed to satisfy. In plain terms: an attacker who can trick the system into decrypting chosen ciphertexts still learns nothing about the real key.
A domain-separation value QHelm binds into every wrap operation, tying it to a specific account, tenant, or surface so a captured wrap can't be replayed elsewhere.
Open Quantum Safe's production cryptographic library. QHelm's pure-Python ML-KEM implementation (used in the public demo) is functionally identical to, and swaps in for, the liboqs implementation used in production — a one-function change, not a rebuild.
The specific elliptic curve Bitcoin (and Ethereum) uses for ECDSA and Schnorr signatures. This is the exact math Shor's algorithm targets.
The two signature schemes used across Bitcoin. ECDSA secures legacy and SegWit outputs; Schnorr (BIP-340) secures newer Taproot outputs. Both rely on the same underlying elliptic-curve hardness assumption, and both fall to Shor's algorithm equally.
Bitcoin's proposed protocol-level quantum upgrade — Pay-to-Quantum-Resistant-Hash, a new output type committing to a post-quantum signature scheme. Important, but insufficient alone: it can't retroactively protect coins already sitting in exposed addresses (an estimated ~4 million BTC have their public key permanently visible on-chain) or protect keys held in custody, at rest, today. That's the gap QHelm closes now.
Hardware Security Module — a dedicated physical device that generates and holds cryptographic keys without ever exposing the raw key material. Institutional custody typically requires FIPS 140-3 Level 3 validated HSMs.
Multi-Party Computation — splits a private key into shares distributed across separate parties, so no single party ever holds the complete key. An alternative custody architecture to HSM-based key storage; QHelm wraps keys regardless of which architecture a custodian already runs.
The standard API most HSMs expose for accessing the cryptographic tokens inside them — the integration surface QHelm connects to rather than replacing.
QHelm's core architectural principle: the classical private key is rewrapped inside a post-quantum envelope. The underlying key itself is never rotated, moved, or exposed — which is why integration takes days, not a re-custody event.
Evaluates controls against the Trust Services Criteria over time, not a point in time. QHelm's Argus monitoring layer is built to produce the structured evidence a SOC 2 examination expects.
New York State's cybersecurity regulation for licensed virtual-currency businesses and other regulated financial entities — one of the more specific state-level frameworks referencing cryptographic controls directly.
The international information-security management standard; Annex A.12 covers operations security, including logging and change management — the categories a QHelm deployment's audit trail is built to satisfy.
The EU's regulation governing electronic identification and trust services, including qualified electronic signatures and seals — relevant to any QHelm deployment touching EU-regulated custody or identity infrastructure.
The Cybersecurity and Infrastructure Security Agency's published roadmap for post-quantum migration across U.S. critical infrastructure — the federal reference point most institutional buyers benchmark against.
The federal controls catalog. The SC (System and Communications Protection) family covers cryptographic protection directly; the AU (Audit and Accountability) family covers the logging QHelm's Argus layer is designed to feed.