Reference

Addresses, keys and units

Address encoding

bech32; HRP zkas: mainnet · zkastest: testnet · zkasdev: devnet · zkassim: simnet

Version byte

Version::ShieldedOrchard = 9

Raw payload

43 bytes = diversifier(11) ‖ pk_d(32)

Script class

ShieldedOrchard => ScriptClass::NonStandard — a 43-byte script is a raw Orchard recipient

Key tree

32-byte seed → spending key → FVK → IVK, external scope only

Diversified addresses

supported by Orchard, but no shipped component derives index > 0. One wallet, one address

Mnemonics

none. No BIP-39 anywhere. Key material is a raw 32-byte seed, hex-encoded

Units

SOMPI_PER_ZKAS = 100_000_000 — 8 decimals

What each key reveals. The IVK decrypts every incoming note of that seed, irrevocably once shared. The OVK, if attached at send, makes outgoing details recoverable by you. Message signing proves address control without spending but discloses the FVK — use a dedicated seed for it.

Emission and supply

The dev fee is skimmed from the subsidy, never from transaction fees — value is conserved, and it is appended as one extra coinbase output, paid every 1000 blocks as a shielded note.

Long-run inflation is ~2.2% at tail onset (~year 2), decaying toward ~1% and below over decades. Emission is heavily front-loaded: roughly half of all curve issuance happens in the first quarter. The tail is perpetual by design — it funds miner security forever rather than relying on fee revenue.

Consensus parameters

Transaction format and sighash

A shielded transaction is version 2, non-coinbase, with no transparent inputs or outputs. The Orchard bundle travels in the transaction payload.

What the signatures commit to

sighash = BLAKE2b(
    network_domain (genesis hash, 32B)    # binds to this chain
  ‖ flags ‖ value_balance ‖ anchor ‖ action_count
  ‖ for each action:
       nullifier ‖ rk ‖ cmx ‖ cv_net ‖ epk
     ‖ enc_ciphertext ‖ out_ciphertext    # <- the memo IS committed
       # spend_auth_sig excluded: it signs this digest
  ‖ len(tx_context) ‖ tx_context )

tx_context = version ‖ subnetwork_id ‖ lock_time ‖ gas    # 38 bytes

Timelocks. The transaction-level absolute lock_time is real and bound into the sighash, so coarse timeouts work. A per-note relative timelock does not exist and is not a small change — it needs a new note field, a changed note commitment, a new circuit public input and regenerated keys.

Fees are byte-proportional, therefore per-action: 1–2 actions = 0.0186 ZKAS, 38 actions = 0.2458 ZKAS. A flat fee below the node minimum is rejected by relay; the wallet raises it automatically.

Node RPC (shielded)

gRPC. Four shielded methods on top of the inherited Kaspa surface — together the whole trustless client interface: mirror the tree, place a birthday, audit supply, read mining income.

GetShieldedBlocks

RequeststartHash (exclusive chain-block cursor), limit, metadataOnlyResponseblocks[] — per chain block: hash, blueScore, daaScore, timestamp, coinbaseTxid, coinbaseOutputs[] (scriptPublicKey, value, commitment), acceptedActions[] with parallel acceptedTxids[] in applied order; plus reorged (cursor orphaned → rescan) and sinkBlueScore

GetShieldedTreeState

Request—ResponseblockHash, daaScore, size, leaf, ommers[], historyFromDaaScore, historyComplete

GetShieldedSupply

Request—ResponsecumulativeCoinbase, cumulativeFees, cumulativeBurns, poolValue, noteCount, as of a named chain block

GetShieldedCoinbaseRewards

Requestrecipients[] (43-byte hex), startHash, limit = blocks scannedResponserewards[] keyed by (coinbaseTxid, outputIndex), plus scannedBlocks, nextCursor

Coinbase mints are public: recipient and value are visible with no viewing key. A block's coinbase pays its mergeset, not its finder.

Public REST API

Unauthenticated, read-only, over the live mainnet node. Base https://explorer.zkas.info/api. Useful for dashboards, indexers and monitoring without running anything.

/info/blockdag

blockCount, headerCount, difficulty, networkName, tipHashes, pruningPointHash, pastMedianTime

/info/pulse

measured block rate: bps15m, averageBlockTime15m, blocks15m, 15-second blockBins and difficultyBins

/info/shielded

turnstile and tree: anchor, noteCount, nullifierCount, turnstileIn, turnstileOut, emissionPerBlock

/info/coinsupply

circulatingSupply in sompi, emissionModel, maxSupply (null)

/info/blockreward · /info/halving

current subsidy; next reduction amount, DAA score, ETA, percent

/info/miners

per-pool attribution over the last hour: blocks, share, derived hashrate, source, distinctAddresses

/info/merged-mining

peers observed merge-mining, with the Kaspa node each is paired to

/info/network · /info/nodes · /info/relay

peer counts, masked peer subnets, relay credit

/info/work-history · /info/reorgs

difficulty over time; observed reorg depths

/info/fee-estimate

priorityBucket / normalBuckets / lowBuckets with feerate and ETA

/blocks/recent · /blocks/:id

recent blocks with coinbase outputs; one block by hash

/transactions/:id · /transactions/search · /transactions/count

transaction lookup

/health

liveness

B=https://explorer.zkas.info/api

# tip, difficulty, pruning point
curl -s $B/info/blockdag

# network hashrate in PH/s, from MEASURED bps
D=$(curl -s $B/info/blockdag | jq .difficulty)
P=$(curl -s $B/info/pulse    | jq .bps15m)
echo "$D $P" | awk '{printf "%.1f PH/s\n", 2*$1*$2/1e15}'

# shielded pool, tree size, current anchor
curl -s $B/info/shielded

# who mined the last hour, with hashrate share
curl -s $B/info/miners | jq '.miners[] | {label:.key, blocks, share}'

GET /info/shielded
{ "anchor": "3d8ee39caf1cd16dd8dd…88bd6fc9",
  "blueScore": "5512774", "emissionPerBlock": 37.79763149,
  "noteCount": 5752657, "nullifierCount": 139889,
  "turnstileIn": "27029204918145767", "turnstileOut": "0" }

GET /info/pulse
{ "bps15m": 0.9777777777777777, "blocks15m": 880,
  "averageBlockTime15m": 1.0227272727272727, "binSeconds": 15 }

GET /info/halving
{ "currentAmount": 37.79763149, "nextHalvingAmount": 35.67621345,
  "reductionPercent": 5.61, "blocksRemaining": 387168,
  "nextHalvingDate": "in ~4 days", "atTailFloor": false }

Address routes (/addresses/:address/…) are inherited from the Kaspa explorer API and are not meaningful on mainnet — there are no transparent addresses to query.

Wallet API

The full zkas-walletd HTTP surface, its flags, the /api/status field semantics and the payout sizing model live on their own page: Wallets & walletd → endpoints.

Versions and compatibility

Glossary

note

a shielded output holding a value and an owner; the unit of value, and the unit that costs proving time

cmx

note commitment — the tree leaf; hides the note's contents

nullifier

published when a note is spent; prevents double-spending without revealing which note

anchor

a past commitment-tree root a spend proves membership against

frontier

the ~32-node summary of the tree a node keeps instead of the whole tree

witness

the Merkle path from a note to an anchor. Wallets hold their own

FVK / IVK / OVK

full / incoming / outgoing viewing key

turnstile

the public integer ledger bounding value entering and leaving the pool

mergeset

the parallel DAG blocks a chain block merges — and what its coinbase pays

aux-PoW

merged mining: proving work for this chain via a parent chain's block header

sompi

the base unit; 10⁸ sompi = 1 ZKAS

transient mass

Kaspa's size-based transaction cost, 4 per byte, capped at 500,000 for a standard transaction

Toccata

the Kaspa upgrade that shipped covenants and zk verification opcodes — see the Kaspa interface