avalanche_flutter_sdk 0.0.3-dev

The first native Flutter/Dart SDK for the Avalanche network. Pure Dart, no platform channels. Covers C-Chain EVM, Data API (Glacier), P-Chain staking, and X-Chain native assets.

Changelog

All notable changes to avalanche_flutter_sdk will be documented here.

The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

0.0.3-dev

Phase 1 in progress: BIP-39 mnemonic generation implemented and verified in English and Spanish.

Added

• MnemonicStrength: enum with 5 valid BIP-39 entropy strengths
  • words12 (128 bits), words15 (160 bits), words18 (192 bits), words21 (224 bits), words24 (256 bits)
  • Computes bits, bytes, checksumBits, totalBits, wordCount per BIP-39 formula: CS = ENT / 32, MS = (ENT + CS) / 11
• Entropy: BIP-39 entropy generation and checksum computation
  • generate(): cryptographically secure random bytes using FortunaRandom + Random.secure() (consistent with PrivateKey)
  • validate(): throws ArgumentError for invalid entropy sizes
  • computeChecksum(): first ENT/32 bits of SHA256(entropy)
  • toBits(): entropy + checksum as bit list for word index computation
• Wordlist: abstract base class for BIP-39 wordlists
  • wordAt(index): returns word at index 0-2047
  • indexOf(word): binary search O(log n) - valid per BIP-39 sorted spec
  • contains(word): delegates to indexOf
  • validate(): checks length == 2048 and words are sorted
• WordlistEn: official BIP-39 English wordlist (2048 words)
  • Singleton pattern: WordlistEn.instance
  • Source: github.com/bitcoin/bips/blob/master/bip-0039/english.txt
  • First word: abandon (index 0), last word: zoo (index 2047)
• WordlistEs: official BIP-39 Spanish wordlist (2048 words)
  • Singleton pattern: WordlistEs.instance
  • Source: github.com/bitcoin/bips/blob/master/bip-0039/spanish.txt
  • NFKD encoding (per BIP-39 spec); wordAt() returns NFC for callers
  • Accent-insensitive lookup: indexOf('abaco') == indexOf('ábaco')
  • HashMap-based O(1) lookup (binary search invalid for Spanish alphabet where ñ follows n, not unicode order)
  • Case-insensitive: indexOf('Domingo') == indexOf('domingo')
• Mnemonic: BIP-39 mnemonic generation, import, and validation
  • Mnemonic.generate(): generates from cryptographically secure entropy; default 12 words English, configurable strength and wordlist
  • Mnemonic.fromEntropy(): deterministic generation from entropy bytes
  • Mnemonic.fromPhrase(): imports and validates existing phrase; verifies BIP-39 checksum; accepts extra whitespace between words
  • toEntropy(): reconstructs original entropy from word indices
  • toString() returns Mnemonic[REDACTED] - phrase is equivalent in sensitivity to a private key; use phrase getter explicitly
• SDK Documentation & Knowledge Base link added to README
• 192 new unit tests (77/77 → 192/192 total passing)

Verified

• BIP-39 official test vectors (trezor/python-mnemonic/vectors.json):
  • 128-bit all-zeros → abandon abandon ... about (12 words) ✅
  • 128-bit 0x7f...7f → legal winner ... yellow (12 words) ✅
  • 128-bit 0x80...80 → letter advice ... above (12 words) ✅
  • 128-bit 0xff...ff → zoo zoo ... wrong (12 words) ✅
  • 256-bit all-zeros → abandon abandon ... art (24 words) ✅
• Spanish wordlist: 2048 words in NFKD encoding, accent-insensitive lookup verified at runtime
• WordlistEn binary search: wordAt/indexOf round-trip consistent at indices 0, 1024, and 2047

Status

Phase 1 in progress: BIP-39 mnemonics (EN + ES) complete and tested.
Not ready for production use.
Next: HD key derivation (BIP-44) + EVM and X/P-Chain address derivation.

0.0.2-dev

Phase 1 in progress: secp256k1 cryptography implemented and verified.

Added

• PrivateKey: secp256k1 private key generation, import, and export
  • PrivateKey.generate() using FortunaRandom (cryptographically secure pseudo-random number generator)
  • PrivateKey.fromHex() with strict range validation against the curve order n (rejects d <= 0 and d >= n)
  • toHex(), toBytes(): 32-byte big-endian export
  • publicKey getter: derives Q = d * G per secp256k1
  • toString() returns PrivateKey[REDACTED] - key material is never exposed via logs, error messages, or debug output
• PublicKey: secp256k1 public key derivation, import, and encoding
  • PublicKey.fromEcPoint(), PublicKey.fromHex() (accepts both compressed and uncompressed SEC1 encodings)
  • toCompressed(): 33-byte SEC1 encoding - required input for X-Chain/P-Chain address derivation (sha256 + ripemd160)
  • toUncompressed() / toRawUncompressed(): 65-byte and 64-byte encodings - required input for C-Chain/EVM address derivation (keccak256)
  • Value equality (==, hashCode) based on the underlying elliptic curve point
• pointycastle: ^4.0.0 and meta: ^1.15.0 added as dependencies
• 60 new unit tests (18/18 -> 78/78 total passing)

Verified

• secp256k1 curve order n confirmed directly from pointycastle's ECDomainParameters('secp256k1') at runtime: fffffffffffffffffffffffffffffffebaaedce6af48a03bbfd25e8cd0364141
• Private key range validation tested at all boundaries: d=0 (rejected), d=1 (accepted), d=n-1 (accepted), d=n (rejected), d=n+1 (rejected)
• Compressed/uncompressed public key encodings verified to decode to the same elliptic curve point (round-trip equality)

Status

Phase 1 in progress: secp256k1 PrivateKey/PublicKey complete and tested.
Not ready for production use.
Next: CB58 encoding, then EVM and X/P-Chain address derivation.

0.0.1-dev

Phase 1 in progress: SDK skeleton and project architecture.

Added

• AvalancheClient: main entry point for the SDK
  • accepts NetworkConfig for Mainnet or Fuji Testnet
• NetworkConfig: official Avalanche RPC endpoint configurations
  • NetworkConfig.mainnet: Avalanche Mainnet (C-Chain, P-Chain, X-Chain, Glacier API)
  • NetworkConfig.fuji: Avalanche Fuji Testnet (C-Chain, P-Chain, X-Chain, Glacier API)
  • endpoint URLs sourced from docs.avax.network
• NetworkId: enum for Mainnet (1) and Fuji Testnet (5)
• AvalancheException: base exception class for all SDK errors
• analysis_options.yaml with very_good_analysis linter (zero warnings enforced)
• scripts/pre_commit.ps1: local quality gate (format + analyze + test)
• .github/workflows/ci.yml: GitHub Actions CI pipeline
  • format check, static analysis, test suite, coverage threshold (85%), pub publish dry-run
  • daily integration test job against Fuji Testnet (on develop push)
• .github/pull_request_template.md: PR checklist
• CONTRIBUTING.md: branch strategy, commit conventions, code and testing standards
• SECURITY.md: vulnerability reporting policy and key handling rules
• 6 initial unit tests (6/6 passing)

Status

Phase 1 in progress: SDK skeleton, project architecture, and CI infrastructure complete.
Not ready for production use.
Next: secp256k1 key generation, BIP-39 mnemonics (EN + ES), HD key derivation (BIP-44).