Glossary
Terms used throughout the CoinCync documentation. Defined to be approximately consistent with how Monero, Zcash, and Pirate Chain use them, with footnotes where CoinCync diverges.
Anchor. A deterministic chain-history value mixed into the proof-of-work preimage so PoW solutions can’t be precomputed against a hypothetical future chain. Computed by compute_full_anchor(prev_hash, height, timestamp).
Anonymity set. The total population of unspent outputs that could plausibly be the real input of a given ring signature. CoinCync’s anonymity set is the entire UTXO pool minus already-spent outputs. Larger = better privacy.
Atomic units. The smallest indivisible unit of CYNC. 1 CYNC = 10^12 atomic units. All on-chain amounts are stored as atomic units; user-facing displays convert to CYNC.
BIP9 signaling. A miner-driven soft-fork activation mechanism originally from Bitcoin. Miners signal readiness for a CoinCync Improvement Proposal (CIP) by setting a bit in their coinbase. Once SIGNAL_THRESHOLD (1814 of 2016 blocks ≈ 90%) signal in a SIGNAL_WINDOW (2016 blocks), the fork locks in and activates at the start of the next window.
Blinding factor. The random scalar b in a Pedersen commitment C = a·G + b·H. Without b, the commitment to amount a would be deterministic and an attacker could brute-force it. The blinding makes commitments hiding.
Block reward. The amount of CYNC paid out as the coinbase output of a new block. Computed from the emission curve — a mountain curve starting at 143 CYNC/block in year 0–1, decaying through anchor points at years 5 (86), 10 (28), and 13 (7), and flooring at the 1 CYNC/block tail from year 20 onward. Total supply is capped at 250,000,000 CYNC by Constitution Article I.
Bulletproofs+. A range-proof scheme that proves a committed amount falls in [0, 2^64) without revealing it. CoinCync uses Bulletproofs+ (the 2022 improvement on the original Bulletproofs), which is ~96 bytes shorter and ~10% faster to verify.
Caddy. The reverse-proxy / TLS-terminator used in front of every public CoinCync HTTP service (explorer, API, landing). Auto-provisions Let’s Encrypt certs, enforces rate limits, applies security headers. Lives in deploy/explorer/, deploy/api/, and deploy/landing/.
CIP. CoinCync Improvement Proposal. An optional protocol change activated via BIP9 signaling. Listed in src/consensus/fork_signal.rs::DEPLOYMENTS. Does not include constitutional invariants — those cannot be CIP’d.
CLSAG. Concise Linkable Spontaneous Anonymous Group signature. The ring signature scheme CoinCync uses for transaction inputs. Provides sender anonymity (you know “one of these N signed” but not which) plus linkability (the same input can’t be spent twice without producing the same key image).
Commitment. See Pedersen commitment.
Confidential transaction. A transaction where amounts are hidden behind Pedersen commitments and proven valid via range proofs. Every CoinCync transaction is confidential — there is no transparent variant.
Constitution. The set of invariants that will never be broken by the CoinCync maintainers. Documented in Constitution and the repository-root CONSTITUTION.md.
CYNC. The native asset of CoinCync. Singular and plural — “1 CYNC”, “100 CYNC”.
Decoy. A ring member that is NOT the real input. Selected from the chain’s anonymity set by the wallet’s decoy selector (src/crypto/ring_selection.rs) using an age-weighted distribution that matches Monero’s current best practice.
Domain separator. A unique tag prefix on a hash preimage that prevents two hashes computed with different tags from colliding. CoinCync uses domain separators on every protocol hash (coincync/header/v1, coincync/tx-sign/v1, etc.). See Privacy model → Hash domain separation.
Dust output. A UTXO with an amount so small that the fee to spend it exceeds the value. CoinCync’s mempool policy doesn’t formally define a dust threshold; in practice, amounts below ~1000 atomic units are uneconomic to spend.
Effective ring size. The actual ring size used at a given height, possibly clamped above the constitutional minimum if the anonymity set isn’t large enough yet. Computed by effective_ring_size(height, available_outputs) in src/constants.rs.
Federation. Running multiple independent hosts of the same service (explorer, API) under different hostnames (explorer.coincync.network, explorer2.coincync.network, …) so the system has no single point a regulator or DDoS can lean on. The CoinCync alternative to putting everything behind a CDN. See Federation & DDoS.
Genesis block. Block 0 — the hardcoded first block of the chain. The genesis hash is a constant in src/testnet.rs::TESTNET_GENESIS_HASH and src/mainnet.rs::MAINNET_GENESIS_HASH. init_genesis() verifies the computed hash matches the constant; a mismatch is a fatal error.
Hashrate. The rate at which a miner computes PoW hashes, measured in hashes per second (H/s). RandomX hashrates are typically in the kH/s to MH/s range on commodity CPUs.
HSM. Hardware security module. CoinCync does not natively integrate with HSMs in 1.0; wallet keys are stored as encrypted files. HSM support is a future research item.
IBD. Initial Block Download. The process of a fresh node downloading and verifying every block from genesis to the current chain tip. On a synced testnet that’s ~12k blocks; the IBD takes ~10 minutes on commodity hardware.
Key image. The cryptographic value I = x · H_p(x · G) derived from the spend key x of a CLSAG ring input. Published with the signature so the network can detect double-spends without learning which output was spent. Same key image twice = double-spend = block rejected.
LWMA. Linearly Weighted Moving Average. The difficulty-adjustment algorithm CoinCync uses (same as Monero). Responsive to short-term hashrate changes, resistant to time-warp attacks. Implementation: src/consensus/difficulty.rs::calculate_difficulty.
Mempool. The pool of pending (unconfirmed) transactions held in memory by every node. New blocks are built from mempool contents. The mempool runs the same crypto verifiers consensus does — there is no fast path that bypasses verification.
MimbleWimble cut-through (MW cut-through). Phase 2 chain-compression technique where historical transaction graphs collapse, leaving only unspent commitments. Compresses the chain and eliminates traceable transaction history. Activates via CIP-006.
Mnemonic phrase. A 24-word BIP39 phrase that encodes the wallet’s master seed. The only way to recover a wallet if the encrypted file is lost. Memorize, paper-back, or both. Never digital, never online.
Nullifier. See key image. (Different name in Zcash; the concept is the same.)
Pedersen commitment. An additively homomorphic commitment scheme. C = a·G + b·H commits to amount a with blinding b. Two commitments add: C(a) + C(b) = C(a+b). CoinCync uses Pedersen commitments for amounts so the network can verify the balance equation sum(inputs) = sum(outputs) + fee without learning any individual amount.
PoW. Proof of work. CoinCync uses RandomX, and only RandomX, by Constitution Article V. Single memory-hard CPU-biased algorithm, same as Monero. No rotation, no hybrid, no PoS transition path. See Consensus & PoW for the rationale on why single-algorithm is stronger than multi-algo rotation.
Privacy policy. The consensus rule that rejects transparent transactions at the consensus layer (not just the mempool). Implemented in src/consensus/privacy_policy.rs::enforce_privacy_policy. Even a maliciously-crafted block trying to include a transparent transaction is rejected by validate_block.
RandomX. A CPU-friendly, ASIC-resistant, memory-hard proof-of-work algorithm designed for Monero, used as-is by CoinCync as one of the three rotating PoW algorithms per Article V. Uses a 256 MB scratchpad and a virtual machine that interprets randomly-generated bytecode — both of which favor general-purpose CPUs over fixed-function hardware.
Range proof. A zero-knowledge proof that a committed amount falls in a given range without revealing the amount. CoinCync uses Bulletproofs+ for the [0, 2^64) range that’s standard for currency amounts.
Reorg. Chain reorganization. When a node sees a competing fork that has more total work than its current tip, it rolls back blocks on the old tip and applies blocks from the new chain. Implementation: src/chain.rs::add_block.
Ring signature. See CLSAG.
Seed phrase. See mnemonic phrase.
Selective disclosure. Sharing your view key with an exchange or auditor so they can verify your incoming and outgoing payments without being able to spend funds. The view key is read-only; the spend key remains private.
Signing hash. The cryptographic hash that the CLSAG ring signature is computed over. Constructed by Transaction::compute_signing_hash — the single source of truth for the preimage. Both the wallet’s signer and the consensus verifier funnel through this helper. See Transaction format → signing hash.
Spend key. The secret key that authorizes spending an output. Derived from the wallet’s master seed. Never share this. Loss of this key = loss of access to funds.
Stealth address. A receiver-side address scheme where every payment to the same (spend_pub, view_pub) pair generates a fresh, unlinkable one-time output public key. Only the recipient (with their view key) can recognize that an output is theirs.
Tail emission. A constant block reward that kicks in after the early issuance phase ends, providing a permanent baseline mining incentive. CoinCync’s tail is 1 CYNC/block starting at year 20 (height ≈ 5,256,000). Tail issuance continues until the 250 M supply cap is reached — see Emission curve → Supply cap interaction with the tail.
Target block time. The intended interval between blocks. 120 seconds (2 minutes) for CoinCync. The LWMA difficulty adjustment keeps actual intervals close to this target.
Testnet. A live but valueless network used for development, testing, and staging. CoinCync’s testnet has the same code as mainnet but a different network magic, a different genesis, and a faucet that gives free CYNC away.
Tor hidden service. A way of publishing an HTTP service inside the Tor network so visitors reach it without going through a Tor exit node. CoinCync supports .onion mirrors for the explorer and API alongside the clearnet sites. See Tor hidden services.
UTXO. Unspent transaction output. The fundamental unit of state in a CoinCync wallet — every UTXO is an output that the wallet’s view key recognizes and that hasn’t been spent. The wallet’s balance is the sum of unspent UTXOs.
View key. A scalar that lets a holder scan the chain for outputs to a specific address WITHOUT being able to spend them. Enables selective disclosure: show your view key to your accountant, prove a transaction is yours to a regulator, etc., all without giving up spending authority.
View tag. A 1-byte filter on every output that lets a wallet reject 255/256 outputs without doing a full ECDH computation — speeds up scanning by ~250×. Optional; activated via CIP-001.