Bitcoin Post-Quantum Infrastructure

Make Bitcoin
quantum-resistant.

BPQI is an open-source Bitcoin protocol implementation that adds a practical post-quantum authorization and migration path—built on standardized cryptography, engineered around Bitcoin's existing upgrade mechanisms, and powered by Aegis PQC.

Explore the architecture ↓ View source ↗

01Open Bitcoin codeBitcoin-facing implementation is open source.

02Standardized PQCML-DSA baseline; SLH-DSA diversified recovery.

03Bitcoin-first designConsensus, wallet, migration and test infrastructure.

2quantum attack classes addressed

6implementation architecture layers

13defined engineering deliverables

12month implementation program

SCROLL

01 / THE THREAT

Bitcoin's quantum risk is concentrated—and addressable.

Bitcoin does not need to be reinvented. The critical change is transaction authorization: elliptic-curve signatures become vulnerable to Shor-capable quantum computation, while the UTXO model, proof of work, SHA-256 foundations, fee market and monetary policy can remain intact.

Preserve what remains secure.Replace what becomes vulnerable.

LONG-EXPOSURE01

Public key visible before spend

P2PK, P2TR, reused keys, exposed multisig keys and other long-lived public-key material can become direct targets once a cryptographically relevant quantum computer exists.

SHORT-EXPOSURE02

Public key revealed during spend

Hidden-key outputs become exposed in the mempool. A sufficiently capable attacker could attempt to derive the classical key and race the legitimate transaction before confirmation.

BPQI RESPONSE✓

Quantum-resistant authorization

Migrated outputs authorize spends with post-quantum signatures, so exposing the public key no longer creates the elliptic-curve private-key recovery path BPQI is designed to eliminate.

Post-quantum authorization layer

MINIMAL CONSENSUS DISRUPTION

Stronger cryptography. Familiar Bitcoin.

Consensus model

BPQI does not replace proof of work or Bitcoin's UTXO accounting model.

Transaction model

The implementation extends authorization through Bitcoin-native witness and script semantics.

Monetary policy

No changes are required to Bitcoin's supply rules, issuance schedule or economic model.

Hashing foundation

SHA-256 remains foundational; the categorical Shor vulnerability sits in public-key authorization.

02 / ARCHITECTURE

One deterministic boundary between Bitcoin consensus and post-quantum cryptography.

BPQI does not put a general-purpose crypto runtime in charge of consensus. Bitcoin defines the accepted algorithm, encoding, sighash semantics, resource rules and failure behavior. Aegis performs the selected standardized cryptographic operation behind a pinned, deterministic interface.

BITCOIN CONSENSUS

Defines validity.

Accepted algorithms
Key + signature formats
Signature message
Resource accounting
Invalid-spend semantics

AEGIS-BTC

Deterministic Verifier

NO ENTROPYNO NETWORKBOUNDED MEMORYFAIL CLOSED

AEGIS PQC

Executes cryptography.

ML-DSA verification
Secure key lifecycle
Provider abstraction
Conformance evidence
Version-controlled releases

01Quantum-resistant output

Bitcoin-native witness or script commitment to a post-quantum authorization condition.

02Signature rule

Consensus-defined verification semantics for supported post-quantum signatures.

03Aegis-BTC verifier

A deliberately narrow, deterministic interface—not the full Aegis application API.

04Wallet + custody

PQ key creation, signing, descriptors, PSBT, backup, recovery and hardware integration.

05Migration infrastructure

Exposure classification and migration planning for existing Bitcoin holdings.

06Assurance + validation

Audit, fuzzing, differential testing, conformance, remediation and independent retesting.

A BITCOIN-NATIVE SPEND PATH

From post-quantum key to confirmed Bitcoin spend.

BPQI keeps the on-chain format compact and Bitcoin-native. Aegis's general-purpose serialization is not copied into witness data; only the consensus information Bitcoin actually needs is carried forward.

01Create PQ keyAegis key-management interface

02Commit outputBitcoin-native script / witness semantics

03Build spendBitcoin signature message + context

04Sign with AegisSelected standardized PQ algorithm

05Verify in consensusPinned Aegis-BTC verifier

06ConfirmQuantum-resistant authorization

P2MR compatible if BIP 360 is activated. OP_SUCCESSx compatible for narrowly scoped Tapscript extension. Bitcoin-owned semantics so runtime configuration cannot alter consensus.

03 / CRYPTOGRAPHIC PROFILE

Deploy with finalized standards. Keep an upgrade path.

BPQI begins with standardized post-quantum signatures rather than waiting for a new cryptographic primitive. Algorithm agility is explicit and consensus-controlled: an algorithm can exist in Aegis before Bitcoin activates it, but local configuration can never make it valid on-chain.

INITIAL BASELINEFIPS 204

ML-DSA-44

Primary interoperability baseline balancing standardized post-quantum security with implementation maturity and Bitcoin block-space requirements.

Public key: 1,312 B
Signature: 2,420 B
Role: Routine PQ authorization

DIVERSIFIED RECOVERYFIPS 205

SLH-DSA-128s

Hash-based diversification for recovery, deep cold storage, emergency spending and low-frequency high-value paths.

Public key: 32 B
Signature: 7,856 B
Role: Conservative fallback

FUTURE BANDWIDTH PATHFIPS 206

FN-DSA

Reserved as a future compact-signature option after FIPS 206 is finalized and the implementation has completed appropriate independent review.

Status: Future option
Priority: Bandwidth efficiency
Gate: Final standard + assurance

04 / MIGRATION

Give Bitcoin somewhere quantum-resistant to move before an emergency.

The migration problem is operational as much as cryptographic. BPQI includes an open-source migration toolkit that classifies wallet-controlled UTXOs by quantum exposure, constructs migration plans and produces quantum-resistant destination outputs.

Exposure scanningBatch migrationFee estimationDestination verificationInstitutional inventoryMigration evidence

bpqi / exposure-classifier

Already-exposed public keysP2PK, exposed multisig, leaked/reused keys

PRIORITIZE

Taproot + reused-key holdingsLong-exposure public-key surface

MIGRATE EARLY

Hidden-key classical outputsShort-exposure risk after spend publication

SCHEDULE

Operationally constrained holdingsDeep cold storage / complex custody

PLAN

05 / ASSURANCE

Security evidence, not vendor self-attestation.

A major part of the program is independent scrutiny of the Bitcoin-relevant Aegis implementation. Qualified auditors and validation laboratories receive the source access necessary to inspect the cryptographic boundary even though Aegis's core repositories are not public.

Cryptographic implementation

Algorithm correctness, parameter enforcement, key generation, signing, verification and error behavior.

Side-channel resistance

Timing behavior, secret-dependent branching, memory-access patterns and platform-specific signing leakage.

Consensus interface

Canonical encoding, malformed-input behavior, deterministic verification, provider equivalence and fail-closed mapping.

Adversarial testing

Fuzzing, negative vectors, pathological verification inputs, allocation pressure and denial-of-service profiling.

Supply chain

Dependency review, release provenance, artifact hashes, signed metadata, SBOM generation and version pinning.

Conformance + validation

Known-answer tests, algorithm conformance, accredited laboratory work where applicable, remediation and independent retest.

Independent verification paths

The Aegis-BTC provider is checked against an independently sourced/reference implementation. Any discrepancy is a release-blocking defect.

PUBLIC TEST CORPUS

06 / IMPLEMENTATION ROADMAP

From specification freeze to release candidate in 12 months.

Workstreams overlap deliberately so Bitcoin engineering, security assurance, migration tooling and public test infrastructure progress in parallel.

MONTHS 1–2

Specification Freeze

Freeze Aegis-BTC v1, ML-DSA-44 profile, API contract, encoding, sighash semantics, resource model and test-vector format.

EXIT → Every consensus-relevant behavior is machine-testable.

MONTHS 2–4

Regtest Implementation

Bitcoin Core verifier, output/spend path, RPC support, wallet prototype, descriptor support, PSBT prototype and benchmark harness.

EXIT → PQ transactions execute deterministically on regtest.

MONTHS 2–7 · PARALLEL

Audit + Validation

Cryptographic review, implementation audit, side-channel analysis, conformance testing, remediation and independent retest.

EXIT → No unresolved critical/high finding in the Bitcoin boundary.

MONTHS 4–7

Migration + Custody

UTXO classifier, migration planner, wallet migration flow, hardware-signing API and institutional custody guidance.

EXIT → Classical regtest holdings migrate end to end into PQ outputs.

MONTHS 6–9

Signet + Interoperability

Public vectors, fuzzing corpus, independent verifier, long-running compatibility tests, signet deployment and performance evidence.

EXIT → Independent implementations agree across the public suite.

MONTHS 9–12

BIP + Release Candidate

BIP-quality specification, final audit evidence, validation evidence, reference implementation, deployment and migration guidance.

EXIT → Complete technical package for Bitcoin developer review.

07 / DELIVERABLES

Not a whitepaper. A complete engineering package.

BPQI's success criteria are tangible and independently testable. Mainnet activation itself is not a grant milestone because Bitcoin's decentralized consensus process controls that decision.

Aegis-BTC normative specification

Algorithms, encodings, verifier contract, context binding, resource limits and security assumptions.

Bitcoin Core reference implementation

Consensus verification, policy, regtest/signet support, RPC interfaces and transaction decoding.

Quantum-resistant output path

Working post-quantum output and spend semantics compatible with the selected Bitcoin upgrade architecture.

Wallet implementation

PQ key generation, signing, descriptors, watch-only support, backups and migration workflows.

PSBT extension

Usable offline and multisystem signing workflow for Aegis-backed Bitcoin transactions.

Migration toolkit

Open-source exposure scanning, prioritization and migration planning software.

Benchmark suite

Key generation, signing, verification, invalid-input cost, memory, fee and block-weight measurement.

Consensus test suite

Positive, negative, malformed, fuzz-derived and differential public vectors.

Independent security audit

Third-party cryptographic and implementation assessment of the Bitcoin security boundary.

Remediation + retest

Material findings resolved and independently verified before release.

Standards / validation evidence

Applicable conformance and formal validation artifacts for the selected Aegis cryptographic boundary.

BIP-quality specification

Publication-ready protocol proposal documenting consensus integration and rationale.

Public signet demonstration

A reproducible environment where developers can create PQ outputs, fund them, sign, broadcast, validate, migrate test coins and independently verify the result.

08 / OPEN SOURCE + LICENSING

Open Bitcoin infrastructure.
Zero Aegis licensing cost for Bitcoin.

All Bitcoin-specific software funded through BPQI is intended to be open source. Aegis remains an independently maintained, patent-pending product, but Synergy Engineering Labs will authorize defined Bitcoin use without licensing fees or royalties.

BPQI / BITCOIN WORKOPEN SOURCE

Bitcoin Core integration, specifications, tests, migration tooling, wallet support, benchmarks, BIP drafts and supporting libraries.

AEGIS PQCBITCOIN AUTHORIZED USE

Separate no-cost Bitcoin-specific authorization while Synergy Engineering Labs retains ownership and non-Bitcoin licensing rights.

WHY GRANT FUNDING MATTERS

The cryptographic platform exists. Funding converts it into independently assured Bitcoin infrastructure.

01Independent cryptographic + security audit

Source-level review of the Aegis capabilities BPQI relies upon.

02Formal validation + conformance

Known-answer tests, standards conformance and specialized laboratory work where applicable.

03Bitcoin protocol engineering

Consensus profile, Core integration, wallet / PSBT work and signet infrastructure.

04Migration + interoperability tooling

Exposure classification, reproducible tests, differential verification and public tooling.

05Remediation + independent retest

Material findings resolved before the release candidate is considered complete.

BITCOIN POST-QUANTUM INFRASTRUCTURE

Build the protection layer before the threat becomes an emergency.

BPQI is designed to give Bitcoin developers a concrete, open, testable and independently reviewed path to post-quantum authorization—without replacing what already makes Bitcoin Bitcoin.

Explore the repository ↗ Read the technical proposal

Make Bitcoinquantum-resistant.