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Transaction Format

Soqucoin uses a UTXO transaction model based on Bitcoin's, with one critical difference: every signature is ML-DSA-44 (NIST FIPS 204) instead of ECDSA. This page documents the byte-exact witness format accepted by soqucoind on the live stagenet.

Witness-v1 layout

Every Soqucoin spend carries a witness with exactly two stack items:

witness = [ sig₂₄₂₀ ‖ 0x01,        // Item 1: signature + SIGHASH_ALL
            0x00 ‖ pubkey₁₃₁₂ ]     // Item 2: key type + public key
Field Size (bytes) Description
sig 2,420 ML-DSA-44 signature (FIPS 204)
0x01 1 SIGHASH_ALL flag
0x00 1 Key type byte (ML-DSA-44 / FIPS-204 form)
pubkey 1,312 ML-DSA-44 public key

Total witness size: 3,734 bytes per input.

Sighash computation

Soqucoin uses BIP-143 sighash with empty-context ML-DSA signing:

  1. Compute the BIP-143 sighash digest (same algorithm as Bitcoin SegWit v0)
  2. Sign with ML-DSA-44 using an empty context string (per FIPS 204 §4.2)
  3. Append SIGHASH_ALL (0x01) to the signature

Address scheme

Addresses use Bech32m encoding (BIP-350):

address = bech32m(hrp, witness_version, witness_program)

hrp              = "ssq" (stagenet) / "soq" (mainnet)
witness_version  = 1
witness_program  = SHA-256(pubkey₁₃₁₂)   // 32 bytes

Example: ssq1p7wk3v5f4e2r8n6h9a1c4d7g0j3m6q2t5x8...

Units

Unit Value
1 SOQ 100,000,000 shors
1 shor smallest unit (like satoshis)

MAX_MONEY = 100,000,000,000 SOQ — this is a validation constant, not a supply cap (Soqucoin has perpetual tail emission).

UTXO model

Soqucoin transactions consume unspent outputs (UTXOs) and create new ones, exactly like Bitcoin. Key differences:

  • No legacy address types. All addresses are witness-v1 (Bech32m).
  • Larger witness. ML-DSA-44 signatures are 2,420 bytes (vs 72 bytes for ECDSA). PAT batch verification compresses this at the block level.
  • 60-second blocks. Target block time is 60 seconds (vs Bitcoin's 10 minutes).
  • Coinbase maturity. 100 blocks before coinbase outputs are spendable.

Verification

This witness format is:

  • Byte-exact against soqucoind consensus (node-proven)
  • Accepted live on stagenet (TS E2E PASS, 2026-06-20)
  • Audited by Halborn (30 findings, all remediated)

Next steps