Windows Indirect Display Driver (IDD) framework. UMDF v2-based driver model for adding virtual monitors that the Desktop Window Manager treats as real displays, then capturing the rendered frames in user mode and routing them somewhere else (network, file, encoder) instead of a physical panel. Covers IddCx callbacks, monitor descriptors (EDID/MCCS), swap-chain processing, cursor handling, hot-plug, hardware cursor, multi-monitor, HDR, and integration with NVENC / Rivermax / RDMA NICs for low-latency network streaming. USE WHEN: user mentions "IDD", "Indirect Display", "IddCx", "IddSampleDriver", "virtual monitor", "virtual display driver", "IDDCX_SWAPCHAIN", "AcquireBuffer", "FinishedProcessingFrame", "EDID for virtual display", "stream desktop", "network display" DO NOT USE FOR: WDDM display miniport drivers (real GPU), DXGK kernel work, Miracast (different framework), Remote Desktop / RDP (different stack)

BOLT (Basis of Lightning Technology) specification index. Wire format, channel management, onion routing, gossip, invoices, feature bits. Quick refs: BOLT-by-BOLT summary, message-type tables, feature-bit registry. USE WHEN: implementing/reading Lightning protocol, looking up message types, debugging interop between implementations.

Spring Shell for building interactive CLI applications. Covers @ShellComponent, @ShellMethod, input validation, tables, and command groups. USE WHEN: user mentions "spring shell", "@ShellComponent", "@ShellMethod", "CLI application Spring", "interactive shell", "command line tool Spring" DO NOT USE FOR: simple scripts - use regular main method, batch processing - use `spring-batch` skill, web endpoints - use `spring-rest` skill

Spring for Apache Kafka integration with KafkaTemplate and @KafkaListener. Covers producers, consumers, retry topics, DLT, and transactions. USE WHEN: user mentions "spring kafka", "KafkaTemplate", "@KafkaListener", "kafka producer Spring", "kafka consumer Spring", "retry topic" DO NOT USE FOR: raw Kafka - use `kafka` skill, RabbitMQ - use `spring-amqp` instead

Deep hard-negative mining for dense retrievers: in-batch vs mined, BM25 / dense / cross-encoder mining, TAS-B, MarginMSE distillation, curriculum schedules, memory banks, false-negative filtering. USE WHEN: user mentions "hard negatives", "negative mining", "TAS-B", "MarginMSE", "distillation from cross-encoder", "curriculum negatives", "memory bank", "MoCo", "false negative filter" DO NOT USE FOR: basic fine-tuning setup - use `embedding-fine-tuning`; reranker training - out of scope; picking a pretrained model - use `embedding-models`

Kernel-Mode Driver Framework (KMDF), the Microsoft-recommended way to write Windows kernel-mode drivers. Covers DriverEntry, EvtDeviceAdd, IRPs and IOCTLs, I/O queues, PnP and Power state machines, IRQL discipline, memory pools, WPP tracing, SAL annotations, and Driver Verifier. USE WHEN: user mentions "KMDF", "WDF kernel", "Windows kernel driver", "DriverEntry", "WdfDriverCreate", "EvtDeviceAdd", "IRP", "IOCTL", "DISPATCH_LEVEL", "PASSIVE_LEVEL", "NTSTATUS", "PoolTag", "WdfRequestComplete" DO NOT USE FOR: UMDF v2 (use `wdf-umdf`), classic WDM-only drivers, file-system filters (FltMgr is a separate framework)

Webpack module bundler. Covers configuration, loaders, plugins, optimization. Use when working with Webpack-based projects or migrating from Webpack. USE WHEN: user mentions "Webpack", "webpack.config", "webpack loaders", "webpack plugins", asks about "Webpack configuration", "bundle optimization" DO NOT USE FOR: Vite projects (use vite skill), esbuild (use esbuild skill), new projects (prefer Vite), Parcel

Near-duplicate and semantic-duplicate detection in corpora before indexing. MinHash / LSH, SimHash, embedding-cosine clustering (DBSCAN), FAISS-based scalable dedup, threshold selection, paraphrase handling. USE WHEN: user mentions "deduplication", "near-duplicates", "MinHash", "SimHash", "LSH", "semantic dedup", "corpus cleaning", "FAISS dedup", "paraphrase detection" DO NOT USE FOR: exact-hash dedup at ingest (use SHA256); chunking decisions - use `chunking-strategies`; drift detection - use `drift-detection`

Modern C++ (C++17/20/23) language and standard library. Covers RAII, move semantics, smart pointers, templates, concepts, ranges, coroutines, modules, std::expected, std::format, std::span, std::string_view. USE WHEN: user mentions "C++", "modern C++", "C++17/20/23", "RAII", "smart pointers", "templates", "concepts", "ranges", "move semantics", "std::expected", "std::span", "coroutines", "modules", "STL" DO NOT USE FOR: C (use a C-specific skill), C# (use `csharp`), Objective-C++, Carbon, kernel/no-exception subset (use `cpp-systems`)

Distributed tracing and observability with Micrometer and Spring Boot 3

pnpm package manager. Fast, disk-efficient with excellent monorepo support. Use when managing dependencies or setting up monorepos. USE WHEN: user mentions "pnpm", "pnpm workspace", "pnpm-workspace.yaml", asks about "pnpm commands", "pnpm install", "workspace protocol" DO NOT USE FOR: npm (use standard npm commands), yarn (use yarn commands), bun package manager

Painting 2D art for dynamic lighting: workflow for Unity 2D Lights / Godot CanvasLight, normal map authoring (Sprite Lamp / hand-painted), separation in layers (diffuse / normal / emissive / mask), self- shadowing in pixel art, day/night palette swaps vs realtime light mixing, glow / emissive layers. USE WHEN: integrating 2D Lights with hand-painted sprites, deciding baked vs dynamic lighting, painting normal maps for pixel art.

Seamless / tileable textures for 2D: offset-and-paint trick, mirror techniques, repetition reduction (variant tiles + decoration overlays), transitional tiles (corner / edge / T-junction), normal map authoring for 2D lighting (Sprite Lamp / Sprite DLight / Materialize), procedural base + hand-pixel overlay, roof/floor/wall specializations. USE WHEN: painting tilesets that don't visibly seam, fixing repetition, adding normal maps to 2D for dynamic lighting, mixing procedural and hand-painted texture.

Visual effects in 2D: frame patterns for smoke / fire / water / electricity, hitstop and hit pause, screen shake intensity curves, particle frames vs procedural particles, juice principles (Vlambeer "Art of Screenshake"), trail effects, color flash, debris, decals. USE WHEN: authoring effect sprites, deciding pre-baked vs procedural particles, designing impact / juice for actions.

Pydantic v2 data validation library. Covers BaseModel, field validators, custom types, serialization, and schema generation. Use when validating data structures, parsing configs, or defining typed data models in Python. USE WHEN: user mentions "pydantic", "BaseModel", "Field()", "model_validator", "field_validator", "Annotated", "model_dump", "model_validate", "pydantic settings", "pydantic v2" DO NOT USE FOR: TypeScript types/interfaces, SQLAlchemy ORM models, dataclasses

Unity 2D gameplay patterns — character controllers (kinematic vs dynamic), coyote time, jump buffer, variable jump height, ledge grab, dash, wall slide, hitstop, juice patterns, top-down 8-way movement. USE WHEN: implementing platformer / metroidvania / top-down character controllers, "feel" tuning, ability layers (dash/double jump/wall slide). DO NOT USE FOR: 2D physics fundamentals (use `unity-2d-physics`); animations (use `unity-2d-animation`); cameras (use `unity-2d-cameras`).

User-Mode Driver Framework v2 (UMDF). User-mode driver model that uses the same WDF object model as KMDF but runs in a host process (WUDFHost.exe) protected by the reflector. Required for some categories (Indirect Display Drivers, many sensor and camera drivers) and recommended for any driver that doesn't strictly need kernel mode. USE WHEN: user mentions "UMDF", "WUDFHost", "user-mode driver", "reflector", "IDD", "ISensor", "WDFHOST", "UMDF v2", "FX2" DO NOT USE FOR: KMDF (use `wdf-kmdf`), classic UMDF v1 (deprecated, COM-based)

CMake build system for C/C++ projects. Modern CMake (3.20+) with targets, properties, presets (CMakePresets.json), FetchContent, find_package, generator expressions, install rules, vcpkg/Conan integration. USE WHEN: user mentions "CMake", "CMakeLists.txt", "CMakePresets", "find_package", "FetchContent", "target_link_libraries", "vcpkg", "Conan", "C++ build" DO NOT USE FOR: Make, autotools, Bazel, Meson, Visual Studio .vcxproj direct editing

Python static analysis with ruff, mypy, pyright. Type checking and linting best practices. USE WHEN: "type checking", "mypy", "pyright", "ruff", "linting", "static analysis", "type error", "type hints", "pylint", "flake8", "black", "isort", "code quality" DO NOT USE FOR: Basic type hint syntax - use languages/python skill DO NOT USE FOR: Runtime validation - use Pydantic

Bulk engineering approaches, tools, and implementation strategies for mass-generating PLC/DCS control logic, HMI displays, and I/O configurations from engineering databases. Use when planning or implementing automation of DCS engineering workflows.

Event Sourcing and CQRS patterns. Event stores, projections, snapshots, command handlers, query models, and eventual consistency. Covers EventStoreDB, Axon Framework, and custom implementations. USE WHEN: user mentions "event sourcing", "CQRS", "event store", "projection", "command handler", "read model", "write model", "EventStoreDB", "Axon" DO NOT USE FOR: simple event-driven architecture - use `event-driven`; message brokers - use messaging skills; DDD basics - use `ddd`

NgRx Store, Effects, Entity, and ComponentStore for Angular state management. Covers reactive patterns with signals integration. USE WHEN: user mentions "NgRx", "Angular state management", "NgRx Store", "NgRx Effects", "NgRx Entity", "ComponentStore", "Angular Redux" DO NOT USE FOR: Redux Toolkit - use `redux-toolkit`, Zustand - use `zustand`, Pinia - use `pinia`, simple Angular signals state

Python package management with uv, poetry, PDM, and pyproject.toml. USE WHEN: "uv", "poetry", "pdm", "dependencies", "virtual environment", "pyproject.toml", "pip", "package management", "lockfile", "venv", "pip install", "requirements.txt", "pip freeze" DO NOT USE FOR: pip commands for running installed tools (use Bash) DO NOT USE FOR: conda/mamba environments - different ecosystem

Unity 2D physics — Rigidbody2D body types, Collider2D shapes, joints, effectors, layer collision matrix, contact filters, IEEE physics gotchas in 2D, raycast/overlap APIs. USE WHEN: tuning Rigidbody2D movement, joint setups (hinge/spring/distance/ slider), one-way platforms, conveyor belts, area effects, layered collisions, raycast queries. DO NOT USE FOR: 3D physics (use `unity-physics-anim`); platformer character movement (use `unity-2d-gameplay`); tilemap collision (use `unity-2d-tilemap`).

Unity 2D Tilemap — Grid + Tilemap, Rule Tiles, Animated Tiles, Tile Palette, Hexagonal/Isometric grids, Composite Collider 2D + Tilemap Collider 2D, procedural tilemap generation. USE WHEN: building level geometry from tiles, painting auto-tiling terrain, isometric/hex maps, optimising tilemap colliders, runtime tilemap generation. DO NOT USE FOR: free-form sprites (use `unity-2d-core`); platforming movement (use `unity-2d-gameplay`); 2D physics general topics (use `unity-2d-physics`).

Discreet Log Contracts: smart contracts on Bitcoin via oracle attestations + adaptor signatures. Oracle publishes nonces upfront, reveals signed outcomes; CETs (Contract Execution Transactions) enforce payouts. No on-chain footprint of the contract logic. USE WHEN: building betting / prediction markets, parametric insurance, derivatives, oracle-driven settlements on Bitcoin.

FROST (Flexible Round-Optimised Schnorr Threshold): t-of-n threshold signing on secp256k1. n participants share a key via Distributed Key Generation (DKG) or trusted dealer; any t can produce a Schnorr signature. Differs from MuSig2 (which is n-of-n). USE WHEN: t-of-n threshold custody (e.g., 3-of-5 board signatures) with single-sig appearance on chain, federated services, multi-sig with availability.

Miniscript: structured subset of Bitcoin Script with fragment types, satisfaction analysis, malleability resistance. Policy → Miniscript → Script compilation. Used in descriptors (wsh + tr) and modern wallets to express spending conditions safely. USE WHEN: composing complex spending conditions, deriving the cheapest satisfaction, ensuring scripts are non-malleable.

BIP331 package relay + accompanying mempool policy: package validation, ancestor/descendant limits, submitpackage RPC, package CPFP, sibling eviction with TRUC v3 (BIP431), ephemeral anchors. Critical for Lightning fee bumping and any multi-tx workflow. USE WHEN: implementing CPFP, designing fee-bump strategies, debugging "why won't my child confirm", reasoning about Lightning anchor pinning.

Reference for major DCS/PLC platforms - ABB Freelance, Siemens PCS7/TIA Portal, Emerson DeltaV, Honeywell Experion. Use when comparing platforms, mapping function blocks across vendors, or designing cross-platform solutions.

Unity project conventions — folder layout, asmdef structure, naming, source control (.gitignore + LFS + force text serialization), prefab variants, ScriptableObject-based architecture. USE WHEN: starting a new Unity project, refactoring an unhealthy one, setting up source control, organising assets, deciding on naming. DO NOT USE FOR: specific systems (use feature-specific skills).

Unity Netcode for GameObjects (NGO) — NetworkBehaviour, NetworkVariable, RPCs (Server/Client/Owner), client-side prediction, lag compensation, Multiplay/Relay/Lobby integration. USE WHEN: building multiplayer (co-op, competitive, MMO-lite), network authority decisions, anti-cheat, matchmaking + relay. DO NOT USE FOR: P2P state-sync without NGO (Mirror, Photon — out of scope); ECS-native networking (NetCode for Entities — adjacent stack).

Unity 3D physics (Rigidbody, Collider, Joints) and animation (Animator state machines, parameters, layers, Animation Rigging, Humanoid retargeting, blend trees). USE WHEN: tuning rigidbody movement, designing Animator state machines, blending animations, layer collision matrix, joints/constraints, motion warping, IK setups. DO NOT USE FOR: 2D physics or 2D animation (use `unity-2d-physics` / `unity-2d-animation`); ECS physics (use `unity-dots`).

BIP32 hierarchical deterministic key derivation: master key from seed, hardened vs unhardened derivation, xpub/xprv encoding, fingerprints, child-key chaining, key origin paths. USE WHEN: building HD wallets, deriving addresses, parsing xpubs, validating descriptors with key origin.

Output descriptors: BIP380-385 family. Descriptor language for declaring scriptPubKey templates with key origin info, ranges, checksums. Functions: pkh, wpkh, sh, wsh, tr, multi, sortedmulti, multi_a, addr, raw, combo, rawtr. USE WHEN: importing watch-only wallets, defining multisig, declaring scan ranges, exchanging key info between wallets.

Generic Bitcoin message signing: BIP137 (legacy P2PKH-only) and BIP322 (modern, supports any output type). Used for proof-of-ownership, withdraw verification, federated authentication, exchange KYC-free attestation. USE WHEN: implementing "sign this message with your Bitcoin address", verifying ownership of an address, building auth via signing.

Application-level cryptography. Password hashing (bcrypt, argon2), encryption (AES-GCM), digital signatures, key management, and secure random generation. USE WHEN: user mentions "encryption", "hashing", "bcrypt", "argon2", "AES", "cryptography", "digital signature", "key management", "HMAC" DO NOT USE FOR: TLS/HTTPS configuration - use infrastructure skills; JWT tokens - use `jwt`; OAuth flows - use `oauth2`

ISA-5.1 tag naming, ISA-88 batch control, ISA-95 enterprise integration, ISA-18.2 alarm management, and ISA-101 HMI standards reference. Use when working with instrument tags, naming conventions, or plant hierarchy.

Lightning pathfinding and routing: cost models, MPP / AMP / trampoline, blinded paths (BOLT 4 update), apriori probability, pickhardt-payments. USE WHEN: implementing/tuning a routing algorithm, debugging "no route" errors, evaluating pathfinding strategies.

typescript-eslint - ESLint plugin for TypeScript USE WHEN: user mentions "typescript-eslint", "TypeScript linting", "type-aware rules", asks about "no-floating-promises", "TypeScript ESLint config", "@typescript-eslint rules" DO NOT USE FOR: ESLint 9 full setup - use `eslint-biome` skill, Biome - use `eslint-biome`, general quality - use `quality-common`

Bitcoin consensus rules: block validation, transaction validation, soft-fork activation mechanics (BIP9, BIP8, Speedy Trial), nLockTime / nSequence semantics, mempool policy vs consensus distinction. USE WHEN: discussing what makes a tx/block valid, soft-fork deployment, reorg handling, "is this consensus-valid".

ZeroMQ notifications from Bitcoin Core: rawblock, rawtx, hashblock, hashtx, sequence. Subscribe over TCP/IPC, integration patterns for Electrs, BTCPay, Lightning nodes. USE WHEN: building real-time integrations with bitcoind, monitoring mempool sequence, integrating LN nodes.

Fee estimation strategies: local mempool-based (estimatesmartfee), external APIs (mempool.space, BlockCypher), bitcoind's smart-fee algorithm, replacement bidding, fee-rate floor (incremental relay). USE WHEN: choosing a fee for a new tx, evaluating fee-bump amounts, designing fee policy for a service.

Taproot Assets (formerly Taro) by Lightning Labs: client-side validation asset protocol on Bitcoin + Lightning. Multi-asset Lightning channels, AddressV2, multi-hop asset routing. USE WHEN: issuing/transferring assets on Bitcoin, integrating asset Lightning channels, evaluating TAP vs RGB.

Segregated Witness: BIP141 (consensus), BIP143 (sighash), BIP144 (P2P serialization), BIP173 (Bech32 address). Witness segregation, weight units, txid vs wtxid, witness commitment. USE WHEN: working with native segwit (P2WPKH/P2WSH), embedded segwit (P2SH-P2WPKH/P2SH-P2WSH), or understanding the witness discount.

ESLint - pluggable JavaScript/TypeScript linter USE WHEN: user mentions "ESLint", "JavaScript linting", ".eslintrc", asks about "eslint config", "linting rules", "eslint plugins", "flat config" DO NOT USE FOR: Biome - use `eslint-biome` skill, TypeScript-specific - use `typescript-eslint` skill, code quality principles - use `quality-common`

IEC 61131-3 programming languages reference (LD, FBD, ST, IL, SFC), PLCopen standards, program organization units, data types. Use when discussing PLC programming standards or cross-platform compatibility.

BOLT 7 gossip: node_announcement, channel_announcement, channel_update. Sync via gossip_queries, channel range queries, gossip rate limiting, pruning stale announcements. USE WHEN: implementing/debugging gossip sync, managing graph storage, designing rate limits.

Sphinx onion routing for Lightning (BOLT 4): packet structure, per-hop encryption, payload TLV, blinded paths, onion messages. USE WHEN: implementing onion construction/decryption, debugging routing payloads, designing onion-based off-chain protocols.

Channel splicing: splice-in (adding capacity) and splice-out (withdrawing) without closing the channel. Replaces "close and reopen" with one splice tx. USE WHEN: increasing/decreasing channel capacity in production, designing dynamic-balance LSP integrations, planning channel lifecycle.

Watchtower architecture: encrypted breach blob storage, justice transactions, monitoring outsourced for offline channels. Eltoo proposal alternatives, BOLT 13 (proposed). USE WHEN: deploying a watchtower service, evaluating watchtower vendors, designing self-hosted monitoring.

NUnit testing framework with TestCase, SetUp/TearDown, assertions, and parameterized tests for .NET applications. USE WHEN: user mentions "NUnit", "TestCase", "TestFixture", "NUnit assertions", "NUnit parameterized tests", ".NET NUnit" DO NOT USE FOR: xUnit - use `xunit`, MSTest, JavaScript testing frameworks

Bitcoin Core indexes: txindex, blockfilterindex (BIP157/158), coinstatsindex. Disk costs, rebuild times, when each is needed. USE WHEN: choosing which indexes to enable, troubleshooting "txid not found", integrating with electrs / fulcrum / LN nodes.

ECDSA signatures over secp256k1: sign/verify, deterministic-k (RFC6979), low-s (BIP146), DER encoding, malleability, recoverable signatures. USE WHEN: signing legacy/SegWit-v0 inputs, verifying legacy signatures, debugging "non-canonical signature" errors.

Babylon: native BTC staking protocol securing PoS chains. Trustless Bitcoin Vaults via BitVM3, integration with Cosmos chains. No bridging / wrapping required. USE WHEN: building BTC-secured PoS chains, integrating Babylon staking, evaluating BTCFi yield options.

Drivechains (BIP300/301) and Spacechains (Ruben Somsen): proposals for sidechains pegged via miner-validated locks or via OP_CAT-like primitives. Status: NOT activated on mainnet. USE WHEN: evaluating proposed sidechain mechanisms, understanding why they're not live, comparing with federated/trustless bridges.

Liquid Network: federated sidechain by Blockstream. Confidential Transactions, asset issuance (LBTC, USDt-Liquid, others), 2-min blocks, n-of-m federation peg-out. Elements codebase. USE WHEN: building on Liquid, peg-in/peg-out integrations, designing CT-based privacy.

Spark by Lightspark: statechain-derived L2 with FROST threshold signatures, leaf architecture, Lightning compatibility. Beta launched April 2025; managed by Spark Operators (SOs). USE WHEN: integrating with Spark, evaluating Spark vs Ark vs Lightning, designing leaf-based UTXO trees.

Inscriptions: arbitrary data committed to specific sats via Taproot envelope structure. Foundation for BRC-20, recursive inscriptions, "Bitcoin NFTs". USE WHEN: creating/parsing inscriptions, debugging inscription flow, evaluating inscription cost / fee impact.

Stratum V2: encrypted, miner-driven mining protocol. Job Declaration, Template Provider, allows miners to choose their own tx set. Defeats pool-level censorship. USE WHEN: deploying SV2-capable mining infrastructure, evaluating V1 vs V2, integrating with Braiins Pool / Datum.

Cross-chain atomic swaps: BTC ↔ LTC / BTC ↔ Liquid / BTC ↔ Monero via HTLC or adaptor signature schemes. Trustless swaps without centralized exchange. USE WHEN: building atomic swap services, evaluating cross-chain bridges, integrating with COMIT / submarine-swap variants.

CoinJoin: collaborative tx where multiple users combine inputs to break common-input-ownership heuristic. Wabisabi (Wasabi 2.0), Whirlpool (Samourai), JoinMarket maker/taker. USE WHEN: implementing CoinJoin coordinator/client, evaluating privacy gain, designing post-CoinJoin hygiene.

BOLT12 offers: reusable invoices, blinded paths, recurring payments, multi-asset (Taproot Assets layered). Replaces BOLT11 for many use cases. USE WHEN: implementing/integrating offers, designing recurring payments, evaluating BOLT11 vs BOLT12 trade-offs.

Submarine swaps: atomic on-chain ↔ Lightning conversions via shared HTLC preimage. Boltz protocol, Loop protocol, Peerswap (P2P), trustless variants with adaptor signatures. USE WHEN: building swap services, integrating with Boltz/Loop, designing trust-minimized swap flows.

Simple Taproot Channels (BOLT 9 bit 56): MuSig2-aggregated funding output, Tapscript commitment leaves, taproot-native HTLCs. USE WHEN: enabling taproot channels in your impl, evaluating cooperative-spend privacy gains, designing taproot HTLC scripts.

Coldcard hardware wallets (Coinkite): Mk4, Q. Bitcoin-only firmware, airgap support via SD card / NFC / QR, BIP85, MuSig2 (experimental), Trick PINs. USE WHEN: integrating with Coldcard, supporting Mk4 / Q, designing airgap signing flows.

Ledger hardware wallets: Nano S Plus, Nano X, Stax, Flex. BOLOS app architecture, Ledger Live, secure element, anti-klepto. USE WHEN: integrating with Ledger, supporting Ledger in app, debugging PSBT signing or HW Recovery service issues.

Trezor hardware wallets: Model T, Model One, Trezor Safe 3, Safe 5. Trezor Suite, trezorctl, USB protocol, BIP32 derivation, passphrase support, Shamir Backup. USE WHEN: integrating with Trezor, supporting Trezor in app, troubleshooting Trezor signing.

Citrea: first ZK-rollup on Bitcoin (mainnet 27 Jan 2026), zkEVM, BitVM2 trustless bridge, ctUSD stablecoin, native BTC lending. USE WHEN: building zkEVM apps on Bitcoin, integrating with Citrea, evaluating ZK rollups vs sidechains.

Counterparty: legacy Bitcoin meta-protocol (2014) for assets, DEX, betting using OP_RETURN. Largely historic; still alive with niche use. USE WHEN: dealing with legacy Counterparty assets, understanding pre-Ordinals asset ecosystem, evaluating obsolete patterns.

Rootstock (RSK): EVM-compatible Bitcoin sidechain with merge mining and federation peg. RBTC native token, 30-second blocks, Solidity smart contracts. USE WHEN: building Bitcoin DeFi via EVM contracts, integrating RSK peg, comparing with Stacks / Liquid.

Runes: Casey Rodarmor's UTXO-native fungible token protocol. Activated at halving April 2024. Smaller on-chain footprint than BRC-20, native validation rules. USE WHEN: building Runes apps, comparing with BRC-20 / Atomicals.

Decentralized mining pools: Public-Pool, BraiinsP2Pool, Solo CKPool, Datum (Ocean). Reduce centralization vs traditional pools. USE WHEN: solo mining, evaluating decentralized options, building censorship-resistant infrastructure.

Mining pool reward schemes: PPS, FPPS, PPLNS, PPS+, Score, prop. Block generation queue, share variance, payout cycles. Solo mining vs pooled. USE WHEN: comparing pools, designing reward systems, understanding miner economics.

Signet: signature-based testnet alternatives. Default signet, custom signets (signetchallenge), Mutinynet (30-sec blocks). Faster + more deterministic than testnet. USE WHEN: testing on a public-style network, avoiding mainnet fees but with realistic block timing.

SeedSigner: DIY Bitcoin signing device. Raspberry Pi Zero + camera + screen. Boots from microSD, no permanent state. Stateless airgap signing. USE WHEN: building / supporting SeedSigner, designing stateless signing flows.

embit: Python Bitcoin library designed for embedded / hardware wallets (MicroPython compatible). Used by Specter DIY, Krux, SeedSigner. USE WHEN: building HW signers, MicroPython Bitcoin apps, low-resource Python.

libbitcoin: comprehensive C++ Bitcoin library. Multiple toolkits (libbitcoin-system, libbitcoin-server, libbitcoin-explorer). Alternative implementation focused on cleanliness. USE WHEN: studying alternative Bitcoin codebases, building C++ Bitcoin services.

lnd Go libraries: lnrpc (gRPC client), chantools (channel utilities), loopd (Loop client), poold (Pool client), neutrino (BIP157/158 SPV). USE WHEN: building Go apps integrating with LND, Loop, or running Neutrino light clients.

python-bitcoinlib by Peter Todd: low-level Bitcoin primitives in Python. Tx, Script, Address, key types, RPC client. USE WHEN: scripting Bitcoin operations in Python, low-level manipulation, Bitcoin Core RPC integration.

@scure/btc-signer: modern audited Bitcoin signer in TypeScript. Pure functional, minimal dependencies, browser-friendly. USE WHEN: building modern web/mobile Bitcoin apps, evaluating bitcoinjs-lib alternative.

Atomicals protocol: alternative metaprotocol family with ARC-20 (fungible) and AVM (Atomicals VM) for richer logic. UTXO-bound digital objects. USE WHEN: working with Atomicals, comparing with Ordinals / Runes.

ASIC mining firmware: Braiins OS+, Vnish, BUMa, stock firmware, custom firmware tradeoffs. Overclocking, undervolting, autotuning, efficiency curves. USE WHEN: deploying mining firmware, evaluating efficiency vs hashrate, choosing custom vs stock.

Bitcoin Proof of Work: SHA256d on block header, target, nonce iteration, hashrate, mining math. USE WHEN: explaining mining mechanics, debugging mining software, designing mining-related apps.

Dandelion++ (BIP156): tx broadcast privacy. Stem phase (forward to one peer) → fluff phase (gossip to all). Hides origin IP. USE WHEN: evaluating tx-broadcast privacy, implementing Dandelion- aware relay logic.

P2P KYC-free Bitcoin exchanges: Bisq (desktop, Tor), RoboSats (Tor / browser, Lightning), Hodl Hodl (web, multisig escrow). USE WHEN: evaluating KYC-free buy/sell options, integrating P2P trading.

Krux: DIY airgap signer running on Sipeed M5StickV / Maix Amigo. Open-source, multi-language, stateless. USE WHEN: integrating Krux, evaluating M5StickV-based signers.

Fulcrum: cppbtc-team Electrum-protocol indexer in C++. Faster than electrs for high-volume queries. Serves Electrum clients + LN nodes. USE WHEN: deploying high-load Electrum server, comparing with electrs.

Botanix: EVM-compatible Bitcoin L2 using "Spiderchain" architecture (federated multisig rotated by orchestrators). stBTC native staking. USE WHEN: deploying EVM apps on Botanix, evaluating Spiderchain vs other federation models.

B² Network (BSquared): hybrid ZK + optimistic Bitcoin L2 with EVM compatibility. Live since 2024. USE WHEN: evaluating B² for deployment, integrating with their bridge, comparing Bitcoin L2 options.

MAP Protocol: omnichain interoperability layer with Bitcoin integration. Cross-chain messaging across many chains; positions itself as Bitcoin L2 connector. USE WHEN: building cross-chain apps spanning Bitcoin + others.

Merlin Chain: largest Bitcoin L2 by TVL (2026), ZK rollup with EVM, 150+ dApps. Federation peg with planned trust-minimization. USE WHEN: evaluating Merlin for deployment, BTC DeFi.

Strata by Alpen Labs: ZK rollup on Bitcoin, BitVM-based bridge, EVM-compatible execution. Emerging Bitcoin L2 in 2025-2026. USE WHEN: evaluating Strata for deployment, comparing with Citrea.

btcsuite: collection of Go Bitcoin libraries. btcec (secp256k1), btcutil (helpers), txscript (Script engine), wire (P2P). USE WHEN: building Bitcoin Go apps, integrating with LND / btcd.

taproot-assets daemon (tapd): Go implementation of Taproot Assets Protocol by Lightning Labs. Companion to LND. USE WHEN: integrating with tapd, building Taproot Assets apps in Go.

# Canvas / WebGL Skill