blockchainkit 0.3.0

Added

• blockchainkit.contracts, a sixth subpackage on designing, breaking and
  verifying smart contracts, with a history page of 17 breakthroughs, each
  with its own gallery example, from Floyd and Hoare (1967-1969) to
  Beanstalk's flash-loan governance attack (2022), and an exercise page.
  New APIs: the world-state model World and Contract (call,
  delegatecall, send, CREATE and CREATE2, events, selfdestruct, gas,
  per-call rollback, invariants) with create_address and
  create2_address; weakest_precondition, check_triple and
  run_program; symbolic_execute, symbolic_bytecode (for vm
  programs) and solve; requires and ensures; fuzz and shrink;
  Ricardian contracts; Mint and Purse; ERC-20 and ERC-721 tokens; King
  of the Ether, GovernMental, block-hash and commit-reveal lotteries; the
  Parity wallet libraries; naive and EIP-1967 proxies; a CREATE2 factory;
  and flash-loan governance. Plots: plot_call_tree,
  plot_symbolic_paths and plot_storage.
• blockchainkit.economics, a seventh subpackage on incentives, fees and
  markets, with a history page of 16 breakthroughs, each with its own
  gallery example, from Schelling's focal points (1960) to proposer-builder
  separation (2022), and an exercise page. New APIs: coordination_probability
  and schelling_round; first- and second-price auctions, virtual values,
  equilibrium bids and expected revenue; the logarithmic market scoring
  rule; block_subsidy, issued_supply and double_spend_incentive;
  simulate_block_rewards, mining_gap and undercutting_payoffs;
  optimal_mining_revenue and honest_mining_is_equilibrium;
  next_base_fee and simulate_fee_market; amount_out,
  impermanent_loss and the ConstantProductPool contract; Dai's
  VaultEngine with Stablecoin and PriceFeed; the OracleLender and
  OracleAttacker contracts; priority_gas_auction, sandwich_profit and
  sandwich_attack; and simulate_pbs. Plots: plot_fee_market,
  plot_constant_product and plot_gas_auction. The model boundaries page
  gains an "Economic models" section.
• blockchainkit.channels, an eighth subpackage on layer-2 scaling and
  interoperability, with a history page of 16 breakthroughs, each with its
  own gallery example, from Reed-Solomon codes (1960) to the Ronin and
  Wormhole bridge exploits (2022), and an exercise page. New APIs:
  rs_encode, rs_recover and rs_decode (Berlekamp-Welch);
  SpilmanChannel, DuplexChannel with invalidation_locktimes,
  LightningChannel (revocation keys, shachain secrets, penalties),
  EltooChannel, and the StateChannel and PreimageManager contracts,
  all with Script outputs checked by vm.verify_script; Watchtower,
  make_appointment and PISA's tower_liable; ChannelNetwork for
  multi-hop HTLC routing and probe_balance; AtomicSwap; the BTCRelay
  contract and mine_header; ValidatorBridge, GuardianVerifier and
  WormholeBridge; PlasmaChain with Plasma Cash exits;
  shard_failure_probability and atomix_transfer; ZKRollup,
  OptimisticRollup and bisect; and extend, simulate_sampling and
  encoding fraud proofs for data availability. Plots: plot_shares,
  plot_route and plot_detection. The model boundaries page gains a
  "Channels, rollups and bridges" section.
• blockchainkit.proofs, a ninth subpackage on zero-knowledge and succinct
  proof systems, with a history page of 16 breakthroughs, each with its own
  gallery example, from the Schwartz-Zippel lemma (1980) to Halo (2019),
  and an exercise page. New APIs: polynomial arithmetic, interpolation and
  the FFT over the BabyBear field (FIELD_PRIME) and a Fiat-Shamir
  Transcript; identity_test; sumcheck and multilinear_extension;
  tqbf_protocol; hadamard_proof and pcp_verify; kilian_argument,
  micali_proof and verify_cs_proof; a toy supersingular
  PAIRING_CURVE with the Tate pairing; KZG (trusted_setup,
  kzg_commit, kzg_open, kzg_verify, forge_opening); powers-of-tau
  ceremonies (contribute, verify_contribution); the R1CS builder
  Circuit, r1cs_to_qap and qap_divide; Groth16; MiMC and a Zerocash
  ShieldedPool with prove_spend; PlonkCircuit and PLONK with
  permutation_product; Bulletproofs range_proof; fri_prove and
  fri_verify; a Fibonacci stark_prove; and Halo's ipa_open,
  ipa_defer, accumulate and decide. Plots: plot_field_polynomials,
  plot_proof_sizes and plot_copy_constraints. The model boundaries page
  gains a "Proof systems" section, and blockchainkit.constants the
  TRANSCRIPT_DOMAIN, IPA_GENERATOR_DOMAIN and MIMC_DOMAIN tags.
• blockchainkit.fraud, a tenth subpackage on financial fraud on and
  around blockchains, with a history page of 17 breakthroughs, each with its
  own gallery example, from Ponzi's scheme (1920) to address poisoning
  (2022-2023), and an exercise page. New APIs: simulate_ponzi,
  breakeven_growth, simulate_lending_ponzi and referral_commissions;
  the ChainPonzi contract with value_flows and ponzi_features;
  benford_test; the MerkleSumTree with verify_sum_proof,
  liability_tree, audit and reserve_ratio; Provisions-style proofs of
  solvency (SolvencyProver, verify_solvency, OR proofs and bitwise
  range proofs over Pedersen commitments); reissue_missing and the
  Custodian contract; verify_source and effective_code; the
  TokenSale (DAICO) contract; seven Torres et al. honeypot contracts with
  explorer_view; SellBlockToken, HiddenMintToken and sell_test;
  simulate_bot_market, return_by_activity, simulate_pump_and_dump
  and detect_pumps; find_wash_trades and simulate_nft_market; the
  Drainer contract with open_approvals and allowance_exposure; and
  grind_lookalike and poisoning_suspects. Plots: plot_ponzi,
  plot_benford and plot_price_spikes. The model boundaries page gains
  a "Fraud models" section, and blockchainkit.constants the
  SUM_LEAF_DOMAIN, SUM_NODE_DOMAIN, SOLVENCY_DOMAIN and
  LOOKALIKE_DOMAIN tags.
• blockchainkit.privacy, an eleventh subpackage on anonymity and
  confidentiality on public ledgers, with a history page of 15
  breakthroughs, each with its own gallery example, from Chaum's mix-nets
  (1981) to Tornado Cash (2019), and an exercise page. New APIs: MixNode,
  seal, wrap and mix_cascade; circuit_compromise_rate,
  simulate_flows and match_flows; k_anonymity, equivalence_classes
  and effective_anonymity_set; ring_sign and ring_verify;
  lsag_sign, mlsag_sign, key_image and linked; simulate_payments,
  cluster_addresses and score_clusters; stealth_keys,
  stealth_payment, owns_output and one_time_secret; coinjoin and
  link_change; the RSA accumulator, ZerocoinPool and
  prove_zerocoin_spend; ring-signature range proofs and
  verify_confidential; ringct_spend and verify_ringct;
  mimblewimble_transaction, aggregate and cut_through; the TumbleBit
  Tumbler with run_tumbler; simulate_rings, chain_reaction and
  trace_rings; and the Mixer contract with prove_withdrawal and
  mixer_report, proving with the Zerocash circuit of proofs. Plots:
  plot_cluster_sizes, plot_ring_positions and plot_anonymity_sets.
  The model boundaries page gains a "Privacy models" section, and
  blockchainkit.constants the MIX_DOMAIN, RING_DOMAIN,
  KEY_IMAGE_DOMAIN, STEALTH_DOMAIN, KERNEL_DOMAIN,
  ACCUMULATOR_DOMAIN and TUMBLER_DOMAIN tags.
• blockchainkit.wallets, a twelfth subpackage on keys as users actually
  hold them, with a history page of 15 breakthroughs, each with its own
  gallery example, from BCH codes (1959-1960) to ERC-4337 account
  abstraction (2021), and an exercise page. New APIs: BCHCode and
  minimal_polynomial; verhoeff_digit, luhn_digit and
  detection_rates; pbkdf2 and crack_pin; scrypt, salsa20_8,
  block_mix and romix with a memory-time trade-off; Base58Check,
  p2pkh_address and is_valid_address; bech32_encode,
  bech32_decode, segwit_encode, segwit_decode and p2wpkh_address
  for Bech32 and Bech32m; serialize_script, multisig_redeem_script
  and verify_p2sh; BIP32's master_key, derive_private,
  derive_public, serialize_extended_key and recover_parent_private;
  BIP39's entropy_to_mnemonic and mnemonic_to_seed; BIP44's
  derive_path and discover_accounts; brain_wallet_key and
  simulate_brain_drain; ecdsa_sign and ecdsa_verify;
  threshold_keygen and threshold_sign; the SocialRecoveryWallet
  contract with recovery_risk; and ERC-4337's EntryPoint,
  SmartAccount and bundle. Utilities: RIPEMD-160 and hash160,
  compressed secp256k1 keys, and GF(2**m). Plots:
  plot_detection_rates, plot_memory_tradeoff and plot_recovery_risk.
  The model boundaries page gains a "Wallet models" section, and
  blockchainkit.constants the HARDENED_OFFSET, BIP32_SEED_KEY,
  BIP39_SALT_PREFIX, MAX_SCRIPT_ELEMENT_SIZE and
  USER_OPERATION_DOMAIN constants.
• World.fork() in blockchainkit.contracts: an independent copy of the
  world state on which to try transactions, as a wallet simulates one
  before sending it.
• Domain tags for contract addresses, block hashes, Ricardian contracts,
  lottery commitments and wallet approvals in blockchainkit.constants,
  and for channel states, Plasma transfers, rollup state, bridge
  withdrawals and watchtower appointments,
  and a "Contract world model" section in the model boundaries page.

Fixed

• consensus.systems.fork_choice imports structures only for type
  checking, so a subpackage that loads structures before consensus no
  longer hits a circular import.
• FinalityGadget no longer depends on vote arrival order: justification and
  finality are recomputed over every recorded vote, so a supermajority link
  recorded before ...

blockchainkit 0.2.0

The package is aligned with its kit-family siblings, and every subpackage now
follows its field through at least 15 breakthroughs, each with its own
experiment.

Added

• Tutorials across subpackages, every line run by the doctest build: Life of
  a payment, Nonces everywhere, Hashes everywhere and Who do you
  trust?.
• Exercise pages, one per subpackage, with 40 worked solutions in collapsed
  boxes, each run by the doctest build. They replace the single solutions page.
• A "Teaching vs production" note on every history entry that adapts a
  deployed protocol, naming the difference.
• README figures, regenerated by docs/make_readme_figure.py and
  docs/make_readme_subpackage_figures.py.
• Execution history: 16 breakthroughs, each with its own gallery example,
  from reverse Polish notation (1924-1957) to the BeautyChain overflow
  (2018). New APIs: execute(..., arguments=...), the Forth words OVER and
  ROT, REVERT, and the shared STACK_EFFECTS table; validate_program;
  assemble (labels); to_rpn and compile_expression; verify_bytecode
  and VerificationResult; run_turing_machine, enumerate_machines and
  busy_beaver (reproducing S(2) = 6); Bitcoin-style Script with
  verify_script, p2pkh_locking/p2pkh_unlocking and htlc_locking
  (OP_CHECKLOCKTIMEVERIFY); the contracts vending_machine and
  batch_transfer (BEC overflow, with a SafeMath option); drain_bank
  (DAO reentrancy); and the plot plot_stack_height.
• Network history: 17 breakthroughs, each with its own gallery example, from
  Erdős-Rényi random graphs (1959) to Dandelion (2017). New APIs: Graph,
  erdos_renyi, ring_lattice, watts_strogatz, barabasi_albert and
  complete_graph; lamport_timestamps, vector_timestamps,
  happened_before and concurrent; spread_rumor (push, pull, push-pull)
  and pittel_rounds; reliable_broadcast (Bracha); ReplicatedRegister
  (CAP); KademliaNetwork, xor_distance and node_id; AddressManager
  and eclipse_probability; relay_cost, compact_block_relay and
  short_id; fork_rate and simulate_fork_rate; first_spy_precision;
  SimulatedNetwork.from_graph and SimulatedNetwork.messages_sent; the
  plots plot_graph, plot_space_time and plot_rumor_spread; and the
  COMPACT_BLOCK_DOMAIN constant.
• Consensus history: 17 breakthroughs, each with its own gallery example,
  from the gambler's ruin (1656) to Casper FFG (2017). New APIs:
  oral_messages (Byzantine generals); ben_or (randomized consensus, also
  used to show the FLP adversary); view_changes (partial synchrony);
  modular_square_root (Dwork-Naor pricing); pbft_round and
  quorum_size; attacker_success_probability (whitepaper section 11, checked
  against its table); retarget and simulate_difficulty; ghost_tip and
  subtree_work; selfish_mining_revenue, selfish_mining_threshold and
  simulate_selfish_mining; fork_voting_payoffs (nothing at stake);
  sortition; and FinalityGadget (Casper FFG with slashing detection).
• Structures history: 15 breakthroughs, each with its own gallery example,
  from double-entry bookkeeping (1494) to Merkle mountain ranges (2016). New
  APIs: Ledger.total_supply; BloomFilter; hash_chain and
  verify_one_time_password; BlockHeader, Block.to_header() and
  verify_header_chain for light clients; bitcoin_merkle_root (Bitcoin's
  duplicated-leaf convention, for CVE-2012-2459); MerkleTree.consistency_proof
  and verify_consistency (RFC 6962/9162); UTXOSet, UTXOTransaction,
  OutPoint and Coin; Transaction.unsigned_id (SegWit-style);
  SparseMerkleTree with membership and non-membership proofs; and
  MerkleMountainRange.
• Cryptography history: 22 breakthroughs, each with its own gallery example,
  from the one-time pad (1917-1949) to MuSig (2018). New APIs behind them:
  one_time_pad/xor_bytes; baby_step_giant_step and pohlig_hellman;
  merkle_puzzles/solve_puzzle; lamport_keypair/lamport_sign/
  lamport_verify; find_collision/truncated_hash; a readable
  Merkle-Damgard SHA-256 (merkle_damgard_sha256, sha256_compress,
  sha256_padding) with length_extension; naive_mac and hmac_sha256;
  pedersen_commit/pedersen_generators; feldman_split/feldman_verify;
  TEACHING_GROUP, a 62-bit safe-prime group; simulate_transcript;
  deterministic_nonce (RFC 6979, checked against the RFC's vectors); and
  musig_coefficients/aggregate_public_keys/musig_sign.
• visualizers/ in every subpackage (Matplotlib, imported explicitly; plain
  import blockchainkit still loads only the standard library):
  plot_curve_points, plot_hamming_distances, plot_merkle_tree,
  plot_proof_trace, plot_block_tree, plot_mining_trials,
  plot_stake_shares, plot_gossip_timeline, plot_execution_trace.
  Matplotlib and NumPy are now runtime dependencies; the examples extra is
  gone.
• execute(..., trace=True) records a TraceStep after every instruction,
  following jumps; a failed run carries its partial trace in VMError.trace.
  execute(..., gas_costs=...) prices opcodes individually (each at least 1).
• MerkleTree.levels, MerkleTree.leaf_count, and trace_proof, which
  returns a MerkleTrace of ProofSteps, even for a proof that fails.
• Blockchain.blocks, tips(), work_at() and state_at() to inspect
  side forks.
• enumerate_points lists every point of a small curve.

Changed

• The documentation follows the kit-family structure: generated hub pages per
  subpackage, per-subpackage API pages, a history/ directory with one
  breakthroughs page per subpackage (each entry with its own References:
  line and minigallery), an examples index, tutorials (the guided course and
  solutions), and JupyterLite launch buttons. Examples moved to
  examples/<subpackage>/<topic>/. The committed per-example notebooks and
  their sync scripts are replaced by sphinx-gallery downloads and a single
  notebooks/quickstart.ipynb.
• The package uses the kit-family layout: one subpackage per domain with
  core/, systems/, utils/ and tests/, shared validation in
  _validation.py, and every consensus-relevant constant in constants.py.
  Public bk.<subpackage>.<name> imports are unchanged.
• A wrong argument type (bool, float, string) now raises TypeError; an
  out-of-range integer still raises ValueError. multiply reports the two
  cases separately.
• Mining varies only the header nonce: Block.merkle_root and Block.hash
  are cached, and Block.header(nonce=...) builds a candidate header without
  rebuilding the Merkle tree. Mining a 20-transaction block is about 59 times
  faster per attempt (2 µs instead of 118 µs).
• verify skips the subgroup-membership multiplications when Hasse's bound
  proves the cofactor is 1 (new Curve.cofactor_is_one), halving the cost of
  verification on secp256k1.
• Ledger, Blockchain, MerkleTree and SimulatedNetwork have readable
  reprs.

Fixed

• Transaction rejects a signature that is not a SchnorrSignature;
  before, the block hash raised AttributeError later.
• execute raises VMError, not TypeError, for a non-string opcode.
• Curve accepts secp256k1's field prime and group order only in their own
  roles; swapping them no longer skips the primality check.
• A receive callback that raises no longer leaves the payload marked seen.
• eventual_catch_up rejects non-numeric fractions, and StakeSampler and
  SimulatedNetwork reject non-integer seeds.