# Scaling and Layer 2 > Source: https://timechain.wiki/wiki/scaling-and-layer-2 · TimechainWiki, the Bitcoin encyclopedia. (sub-MOC · scaling) > The off-chain and adjacent-chain scaling layers of the Bitcoin ecosystem — engineered systems that move value at higher frequency, lower cost, or with different trust assumptions than the base layer. Opens with the SegWit upgrade as the load-bearing base-layer enabler (malleability fix and witness-discount were the preconditions for Lightning's deployability), then organizes into four clusters: **Lightning fundamentals** ([The Lightning Network](https://timechain.wiki/wiki/the-lightning-network.md), [Lightning channels](https://timechain.wiki/wiki/lightning-channels.md), [Lightning routing](https://timechain.wiki/wiki/lightning-routing.md), [Watchtowers](https://timechain.wiki/wiki/watchtowers.md)) cover the deployed dominant Layer-2 system; **Other Layer 2 — sidechains, statechains, ARK, and asset layers** ([Liquid Network](https://timechain.wiki/wiki/liquid-network.md), [Statechains](https://timechain.wiki/wiki/statechains.md), [Spark protocol](https://timechain.wiki/wiki/spark-protocol.md), [Ark protocol](https://timechain.wiki/wiki/ark-protocol.md), [Taproot Assets](https://timechain.wiki/wiki/taproot-assets.md)) cover the non-channel-network architectures and the stablecoin-carrying asset-issuance layers; **Custodial and federated Layer 2** ([Fedimint](https://timechain.wiki/wiki/fedimint.md), [Cashu](https://timechain.wiki/wiki/cashu.md)) cover the chaumian-ecash architectures that trade trust-minimization for usability. Substantive engagement with critiques is in [Network capacity and fee-market critiques](https://timechain.wiki/wiki/network-capacity-and-fee-market-critiques.md) and [Lightning Network operational critiques](https://timechain.wiki/wiki/lightning-network-operational-critiques.md). Adjacent-chain projects without Bitcoin-purist defensibility (RSK; broader EVM-bridge architectures) are out of scope. --- ## How to use this sub-MOC The notes here are arranged in three ways simultaneously: 1. **By cluster** — base-layer enabler / Lightning fundamentals / Other Layer 2 / Custodial-federated, reflecting the trust-assumption and architecture-family structure 2. **By suggested reading order** — SegWit upgrade first (the precondition), then Lightning Network overview, then channel mechanics, then routing, then the non-Lightning architectures 3. **By function** — distinguishing protocol-mechanism notes from system-architecture notes from custodial-Layer-2 notes Each note follows the engineering-reference template variant (Why this matters → mechanism / architecture sections → operational reality → `## Tradeoffs and design choices` → Open questions → Canonical sources → Related notes). Cryptographic primitives are treated as black boxes; mechanism is foregrounded; out-of-scope material defers via wikilink. --- ## The conceptual layering Bitcoin's scaling architecture is layered by design. The base layer (Layer 1) is engineered for monetary settlement at slow tempo with the highest available security guarantees; layers built above it move value at higher frequency with explicit, named tradeoffs. **Layer 0 — The base-layer protocol** (treated in [Technical foundations](https://timechain.wiki/wiki/technical-foundations.md)). **Base-layer scaling enabler — SegWit (2017).** The witness-discount and transaction-malleability fix introduced by the SegWit soft fork are the preconditions for deployable off-chain channel networks. Without SegWit, Lightning channels could not be reliably constructed. **Layer 2a — Lightning Network.** The dominant deployed Layer-2: a peer-to-peer payment-channel network that settles to the base layer on channel-close. Lightning has its own protocol primitives (channels, HTLCs, gossip-and-routing) that this section treats at reference depth. **Layer 2b — Non-channel-network Layer 2 and asset layers.** Sidechains (Liquid; merge-mined chains), statechains (off-chain UTXO transfer with signer rotation; Mercury Wallet single-operator; Spark threshold-signature multi-operator with leaf-architecture partial transfers), and the ARK protocol family (covenant-light virtual UTXO sharing) are architecturally distinct from channel networks and warrant separate treatment. Asset-issuance layers (Taproot Assets; Liquid's Issued Assets) also live here — they issue non-bitcoin assets, overwhelmingly stablecoins, that settle to or ride on Bitcoin infrastructure. **Layer 2c — Custodial and federated Layer 2.** Chaumian-ecash systems (Fedimint; Cashu) trade trust-minimization for usability. They are Bitcoin-denominated by construction but introduce custodial trust at the mint or federation layer. The clusters in this sub-MOC map to these layering distinctions. --- ## Cluster 1 — Base-layer scaling enablers Base-layer protocol upgrades that expand the deployable off-chain scaling design space. - [SegWit upgrade](https://timechain.wiki/wiki/segwit-upgrade.md) — the 2017 soft-fork upgrade that (1) fixed transaction malleability, removing the blocker that had prevented deployable payment channels, and (2) introduced the witness-data segregation and 4× witness discount that effectively increased base-layer throughput. SegWit also introduced bech32 address formats (`bc1q...` v0 and `bc1p...` v1 Taproot). Activation followed the Block Size Wars (see [Block Size Wars - History](https://timechain.wiki/wiki/block-size-wars-history.md)) and the UASF (BIP148) coordinated effort. - [Taproot upgrade](https://timechain.wiki/wiki/taproot-upgrade.md) — the 2021 soft-fork upgrade activating Schnorr signatures (BIP340), MAST-based script trees (BIP341), and the Tapscript script-version mechanism (BIP342). The most significant base-layer protocol upgrade since SegWit; lays the groundwork for advanced multisig, adaptor-signature constructions, and more compact script representations across Layer 2. - [Proposed scaling soft forks](https://timechain.wiki/wiki/proposed-scaling-soft-forks.md) — the active soft-fork proposals under discussion as of 2026 (OP_CTV / CHECKTEMPLATEVERIFY, OP_CAT, CHECKSIGFROMSTACK, others) and their relationship to the Layer-2 design space (Ark, BitVM, vault constructions, channel-factory designs). See [OP_CAT and the covenants programmability debate](https://timechain.wiki/wiki/op-cat-and-the-covenants-programmability-debate.md) (Controversies) for substantive engagement with the most-debated cluster. --- ## Cluster 2 — Lightning fundamentals The deployed dominant Layer-2 system. Three protocol-primitive notes plus one operational-monitoring note. - [The Lightning Network](https://timechain.wiki/wiki/the-lightning-network.md) — overview note: the payment-channel-network architecture, the HTLC primitive, atomic multi-hop payments, the gossip protocol, the operational state of the network, the relationship to the base layer. - [Lightning channels](https://timechain.wiki/wiki/lightning-channels.md) — channel mechanics: channel opening and funding, commitment transactions, the punishment-via-revocation-key model, channel lifecycle (open → use → cooperative close vs force close), splicing, eltoo and PTLCs as proposed upgrades. - [Lightning routing](https://timechain.wiki/wiki/lightning-routing.md) — pathfinding mechanics: source routing, the gossip protocol, fee discovery, trampoline routing, routing-concentration dynamics, the LSP (Lightning Service Provider) architecture that emerged in response to small-user routing difficulty. - [Watchtowers](https://timechain.wiki/wiki/watchtowers.md) — outsourced channel monitoring: the protocol-level need for online channel-monitoring; trust-minimized vs altruistic watchtower models; current deployment state; the eltoo relationship (which would obviate watchtowers for compliant channels). --- ## Cluster 3 — Other Layer 2 — sidechains, statechains, ARK, and asset layers Non-channel-network Layer-2 architectures plus the asset-issuance layers that put non-bitcoin assets (chiefly stablecoins) onto Bitcoin infrastructure. - [Liquid Network](https://timechain.wiki/wiki/liquid-network.md) — Blockstream's federated sidechain: peg-in/peg-out mechanics, the functionary federation, confidential transactions (CT), Issued Assets (including USDt on Liquid), production deployment characteristics, the trust profile. - [Statechains](https://timechain.wiki/wiki/statechains.md) — off-chain UTXO transfer via signer rotation: the architecture (a federation transfers signing rights; the UTXO never moves on-chain during the off-chain transfer), CommerceBlock's reference implementation, the privacy-and-self-custody tradeoff structure. - [Spark protocol](https://timechain.wiki/wiki/spark-protocol.md) — Lightspark's statechain-derived Layer-2: FROST threshold-signature operators (Lightspark + Flashnet as of 2026), the leaf architecture that enables partial-amount transfers (addressing the classical whole-UTXO statechain constraint), 1-of-n honest-operator trust model, Lightning compatibility and native stablecoin support (Wallet of Satoshi, Breez SDK, Tether WDK integrations). - [Ark protocol](https://timechain.wiki/wiki/ark-protocol.md) — covenant-light virtual UTXO sharing: the architecture (ASP-coordinated rounds; virtual UTXOs/VTXOs settle periodically to base-layer transactions), the relationship to OP_CTV/CHECKTEMPLATEVERIFY covenants and the broader covenant debate (see [OP_CAT and the covenants programmability debate](https://timechain.wiki/wiki/op-cat-and-the-covenants-programmability-debate.md)), the covenantless mainnet implementations (Arkade, Bark), current deployment state. - [Taproot Assets](https://timechain.wiki/wiki/taproot-assets.md) — Lightning Labs' Taproot-powered asset-issuance protocol (formerly Taro): assets — overwhelmingly stablecoins — issued on the base layer and transferred over Lightning via same-UTXO asset channels and request-for-quote conversion. Its defining deployment is Tether's USDT going live on Bitcoin and Lightning in March 2026. The Bitcoin-not-crypto tension (assets-on-Bitcoin; custodial issuer) is engaged in its Counter-arguments and deferred to [Custody concentration risks](https://timechain.wiki/wiki/custody-concentration-risks.md) and [OP_CAT and the covenants programmability debate](https://timechain.wiki/wiki/op-cat-and-the-covenants-programmability-debate.md). --- ## Cluster 4 — Custodial and federated Layer 2 Chaumian-ecash architectures: Bitcoin-denominated value with explicit federated or single-mint custody. - [Fedimint](https://timechain.wiki/wiki/fedimint.md) — federated chaumian ecash mint on top of Lightning: the FediMint protocol, the federation-of-guardians trust model, the integration with Lightning for inbound and outbound value flow, the "community bank" use case, current deployment patterns. - [Cashu](https://timechain.wiki/wiki/cashu.md) — single-mint chaumian ecash protocol: the simpler-than-FediMint trust profile (one mint vs federation), Nostr-zap-and-ecash patterns, the deliberate-design-choice rationale for single-mint custody. --- ## Cross-listed critique and controversy notes Substantive analytical critique of scaling architectures lives in dedicated Criticism notes that home elsewhere; cross-listed here for navigation: - [Network capacity and fee-market critiques](https://timechain.wiki/wiki/network-capacity-and-fee-market-critiques.md) _(home: criticisms — substantive engagement; see also light-touch Tradeoffs in [SegWit upgrade](https://timechain.wiki/wiki/segwit-upgrade.md) and [The Lightning Network](https://timechain.wiki/wiki/the-lightning-network.md))_ — the analytical critique of base-layer throughput limits, the fee-market post-halving sustainability question, the small-user pricing-out concern. - [Lightning Network operational critiques](https://timechain.wiki/wiki/lightning-network-operational-critiques.md) _(home: criticisms — substantive engagement; see also light-touch Tradeoffs in [The Lightning Network](https://timechain.wiki/wiki/the-lightning-network.md), [Lightning channels](https://timechain.wiki/wiki/lightning-channels.md), [Lightning routing](https://timechain.wiki/wiki/lightning-routing.md))_ — the analytical critique of Lightning's user-experience friction, custodial-Lightning concentration, routing-concentration concerns, the "Lightning hasn't worked" framing. --- ## Analytical voices anchoring this area Lightning and Layer-2 thinking is anchored by a mix of protocol developers, technical authors, and operational practitioners. **Lightning protocol architects** - [Joseph Poon](https://timechain.wiki/wiki/joseph-poon.md) — co-author of the Lightning Network whitepaper (2015); the payment-channel-network architecture that defined Layer 2. - [Tadge Dryja](https://timechain.wiki/wiki/tadge-dryja.md) — co-author of the Lightning Network whitepaper; MIT DCI; Utreexo (UTXO-set accumulator) and discreet log contracts. - [Olaoluwa Osuntokun](https://timechain.wiki/wiki/olaoluwa-osuntokun.md) — "roasbeef"; Lightning Labs co-founder/CTO; the LND implementation and Taproot Assets. - [Rene Pickhardt](https://timechain.wiki/wiki/rene-pickhardt.md) — Lightning routing and payment-economics researcher; co-author of [Mastering the Lightning Network](https://timechain.wiki/wiki/mastering-the-lightning-network.md). **Lightning technical authors and base-layer engineers** - [Andreas Antonopoulos](https://timechain.wiki/wiki/andreas-antonopoulos.md) — co-author of [Mastering the Lightning Network](https://timechain.wiki/wiki/mastering-the-lightning-network.md) (O'Reilly, 2021) with René Pickhardt and Olaoluwa Osuntokun. The canonical Lightning technical reference. - [Pieter Wuille](https://timechain.wiki/wiki/pieter-wuille.md) — Bitcoin Core developer; co-author of SegWit (BIP141 + BIP143 + BIP144 + related); foundational engineering authority for the base-layer enabler. - [Peter Todd](https://timechain.wiki/wiki/peter-todd.md) — Bitcoin Core developer and consultant; engineered RBF (replace-by-fee), which interacts with Lightning's fee-bumping needs; vocal critic of certain covenant proposals. - [Greg Maxwell](https://timechain.wiki/wiki/greg-maxwell.md) — Bitcoin Core developer (retired); foundational contributor to many primitives the scaling layer rests on (Schnorr, MAST, confidential transactions co-design). **Operational practice and reference** - [Jameson Lopp](https://timechain.wiki/wiki/jameson-lopp.md) — engineer and self-custody specialist; ongoing operational commentary on Lightning's UX trajectory. - [Jimmy Song](https://timechain.wiki/wiki/jimmy-song.md) — Bitcoin developer-educator; teaching-focused engagement with Lightning and Bitcoin Script. Cross-area thinkers cited in this section include [Saifedean Ammous](https://timechain.wiki/wiki/saifedean-ammous.md) (the Lightning-as-medium-of-exchange-emergence framing in [The Bitcoin Standard - Saifedean Ammous](https://timechain.wiki/wiki/the-bitcoin-standard-saifedean-ammous.md)) and [Nik Bhatia](https://timechain.wiki/wiki/nik-bhatia.md) (the layered-money institutional framework from [Layered Money - Nik Bhatia](https://timechain.wiki/wiki/layered-money-nik-bhatia.md)). --- ## Canonical sources for this area - [Mastering the Lightning Network](https://timechain.wiki/wiki/mastering-the-lightning-network.md) (Antonopoulos, Osuntokun, Pickhardt; O'Reilly 2021) — the canonical Lightning technical reference; chapter-level treatment of HTLCs, channels, routing, and operational practice. - [Mastering Bitcoin - Andreas Antonopoulos](https://timechain.wiki/wiki/mastering-bitcoin-andreas-antonopoulos.md) (3rd ed. 2023) — base-layer reference; SegWit and Taproot chapters are load-bearing for this section. - [The Bitcoin whitepaper - Explainer](https://timechain.wiki/wiki/the-bitcoin-whitepaper-explainer.md) — base-layer reference. - [The Blocksize War (book) - Jonathan Bier](https://timechain.wiki/wiki/the-blocksize-war-book-jonathan-bier.md) — the historical context for why SegWit activated as a soft fork and why off-chain scaling became the path forward. - [Layered Money - Nik Bhatia](https://timechain.wiki/wiki/layered-money-nik-bhatia.md) — the institutional-architecture framing for layered monetary systems. **Lightning specification documents** (referenced rather than included as source pages): - The BOLT (Basis of Lightning Technology) specifications at github.com/lightning/bolts — the canonical protocol specs - Various Lightning Implementation working groups: LND (Lightning Labs), Core Lightning / CLN (Blockstream), Eclair (ACINQ), LDK (Lightning Development Kit) --- ## Key connections to other areas **To Technical foundations** - [Soft forks and hard forks](https://timechain.wiki/wiki/soft-forks-and-hard-forks.md) — the upgrade-mechanism framework SegWit operates under; deferral home for protocol-evolution-mechanism content. - [Bitcoin Script and opcodes](https://timechain.wiki/wiki/bitcoin-script-and-opcodes.md) — the scripting layer Lightning's HTLCs and channels are built on. - [Signature schemes in Bitcoin](https://timechain.wiki/wiki/signature-schemes-in-bitcoin.md) — Schnorr/Taproot enables advanced multisig and adaptor-signature constructions that the future Lightning protocol depends on. - [Bitcoin addresses](https://timechain.wiki/wiki/bitcoin-addresses.md) — SegWit's bech32/bech32m address types; cross-referenced from the SegWit note. - [UTXO model and Bitcoin transactions](https://timechain.wiki/wiki/utxo-model-and-bitcoin-transactions.md) — the transaction-graph foundation for all of Layer 2. - [The peer-to-peer network](https://timechain.wiki/wiki/the-peer-to-peer-network.md) — the gossip-and-propagation layer the base layer uses; analogous to (but distinct from) Lightning's gossip layer. **To Self-custody** - [Lightning privacy properties](https://timechain.wiki/wiki/lightning-privacy-properties.md) (home: self-custody, privacy-practice cluster) — the privacy-tradeoff dimension of Lightning; cross-linked from [The Lightning Network](https://timechain.wiki/wiki/the-lightning-network.md) and [Lightning channels](https://timechain.wiki/wiki/lightning-channels.md). - [Hot vs cold storage](https://timechain.wiki/wiki/hot-vs-cold-storage.md) — Lightning channels require hot keys; the operational-security implication is referenced from [Lightning channels](https://timechain.wiki/wiki/lightning-channels.md). **To History and origins** - [Block Size Wars - History](https://timechain.wiki/wiki/block-size-wars-history.md) — the conflict whose resolution established off-chain scaling as the path forward; SegWit was the technical instrument of that resolution. **To Criticisms** - [Network capacity and fee-market critiques](https://timechain.wiki/wiki/network-capacity-and-fee-market-critiques.md) — analytical critique of base-layer throughput limits (substantive engagement homes here; light-touch refer-links from this section's Tradeoffs). - [Lightning Network operational critiques](https://timechain.wiki/wiki/lightning-network-operational-critiques.md) — analytical critique of Lightning's deployment reality (substantive engagement homes here). - [Protocol-evolution constraints](https://timechain.wiki/wiki/protocol-evolution-constraints.md) — analytical critique of how Bitcoin upgrades; relevant for understanding why scaling proceeds as it does. **To Controversies** - [OP_CAT and the covenants programmability debate](https://timechain.wiki/wiki/op-cat-and-the-covenants-programmability-debate.md) — engaged from [Ark protocol](https://timechain.wiki/wiki/ark-protocol.md) (covenants would simplify Ark substantially) and the broader Layer-2-architecture debate. - [BIP-300 and the Drivechains debate](https://timechain.wiki/wiki/bip-300-and-the-drivechains-debate.md) — adjacent-chain proposal that would change the sidechain trust profile; engaged from [Liquid Network](https://timechain.wiki/wiki/liquid-network.md) and the broader sidechain debate. **To Mining** - Mining-economics integration: Lightning's effect on base-layer fee revenue is a load-bearing question for [Long-term security budget](https://timechain.wiki/wiki/long-term-security-budget.md). --- ## What this area doesn't cover To set expectations for what isn't here: - **Non-Bitcoin sidechains and bridge architectures.** RSK (merge-mined Bitcoin sidechain with EVM compatibility) is technically Bitcoin-anchored but lives in an adjacent EVM-altcoin programmability domain that the Bitcoin-not-crypto editorial position treats as out of scope. The broader cross-chain-bridge architecture (wrapped BTC on EVM chains, etc.) is similarly out of scope. - **Pre-Lightning channel proposals.** Spilman channels, the original Hashed Timelock Contract literature, the duplex micropayment channel literature — historically interesting but superseded by Lightning's deployed design. - **Detailed implementation comparisons across Lightning clients.** LND, Core Lightning, Eclair, and LDK each have specific operational profiles; the differences are documented in the canonical Lightning technical reference rather than re-treated here. - **Specific Lightning Service Provider business models.** LSPs are an operational reality of the network; the architecture is referenced in [Lightning routing](https://timechain.wiki/wiki/lightning-routing.md) but specific LSP-as-business-entity treatment is out of scope. - **Ecash protocol theory in depth.** Chaum's blind-signature protocols and the broader ecash literature are referenced in [Fedimint](https://timechain.wiki/wiki/fedimint.md) and [Cashu](https://timechain.wiki/wiki/cashu.md) but the deep cryptographic theory is treated at black-box depth. - **Layer-3 and higher abstractions.** Application-layer protocols built on Lightning (Lightning addresses, Nostr-zap integration, podcasting-2.0 value-for-value) are out of section scope; the network-protocol layer is the focus. --- ## Open questions in this area - **How does Lightning evolve as the base-layer fee market sustains the network post-halving?** The Lightning-base-layer fee relationship is structurally important; the section's treatment of [Lightning channels](https://timechain.wiki/wiki/lightning-channels.md) and [Lightning routing](https://timechain.wiki/wiki/lightning-routing.md) must engage how fee dynamics shape channel-management practice. - **Will the ARK protocol family or another covenant-light Layer-2 supplant Lightning's dominance?** Lightning is currently the dominant deployed Layer-2 but is not the only proposed architecture; the section's treatment of [Ark protocol](https://timechain.wiki/wiki/ark-protocol.md) must engage this honestly. - **What is the appropriate disposition toward custodial-federated Layer 2 (Fedimint, Cashu) in the Bitcoin-self-custody-discipline editorial position?** These systems trade trust-minimization for usability; the Bitcoin maximalist position has internal disagreement about how to engage them. The section treats them as legitimate Bitcoin-denominated tools while acknowledging the trust-tradeoff explicitly. - **How do covenant-enabling soft forks (OP_CTV, CHECKTEMPLATEVERIFY, OP_CAT) affect the Layer-2 architecture landscape?** Several proposed Layer-2 systems depend on specific covenant primitives; the OP_CAT and covenants debate (see [OP_CAT and the covenants programmability debate](https://timechain.wiki/wiki/op-cat-and-the-covenants-programmability-debate.md)) is the load-bearing protocol-evolution question for the section's medium-term future. - **What is the relationship between Layer-2 development and Bitcoin's monetary use cases (store of value → medium of exchange → unit of account)?** Lightning specifically is the medium-of-exchange infrastructure; the section's treatment must engage the [Monetization S-curve](https://timechain.wiki/wiki/monetization-s-curve.md) connection. --- ## Related notes - _MOC-Map-Bitcoin — parent MOC - [Technical foundations](https://timechain.wiki/wiki/technical-foundations.md) — adjacent sub-MOC; base-layer protocol mechanism - [Criticisms of Bitcoin](https://timechain.wiki/wiki/criticisms-of-bitcoin.md) — substantive engagement-with-critics home for scaling critiques - [Bitcoin controversies](https://timechain.wiki/wiki/bitcoin-controversies.md) — event-level engagement-with-controversies home for protocol-evolution debates - [History and origins](https://timechain.wiki/wiki/history-and-origins.md) — historical-narrative home for the Block Size Wars and SegWit activation - [Practical self-custody and sovereignty](https://timechain.wiki/wiki/practical-self-custody-and-sovereignty.md) — operational home for Lightning-privacy practice - [Mining](https://timechain.wiki/wiki/mining.md) — Mining-economics interaction with Lightning's fee-market dynamics - [Mastering the Lightning Network](https://timechain.wiki/wiki/mastering-the-lightning-network.md) — canonical Lightning technical reference - [Mastering Bitcoin - Andreas Antonopoulos](https://timechain.wiki/wiki/mastering-bitcoin-andreas-antonopoulos.md) — base-layer reference; SegWit and Taproot chapters - [Layered Money - Nik Bhatia](https://timechain.wiki/wiki/layered-money-nik-bhatia.md) — institutional-architecture framing for layered monetary systems - [The Blocksize War (book) - Jonathan Bier](https://timechain.wiki/wiki/the-blocksize-war-book-jonathan-bier.md) — historical context for off-chain-scaling resolution - [Soft forks and hard forks](https://timechain.wiki/wiki/soft-forks-and-hard-forks.md) — upgrade-mechanism framework - [Bitcoin Script and opcodes](https://timechain.wiki/wiki/bitcoin-script-and-opcodes.md) — scripting layer Lightning builds on - [Signature schemes in Bitcoin](https://timechain.wiki/wiki/signature-schemes-in-bitcoin.md) — Schnorr/Taproot foundation for advanced Lightning constructions - [Bitcoin addresses](https://timechain.wiki/wiki/bitcoin-addresses.md) — SegWit address-format treatment - [UTXO model and Bitcoin transactions](https://timechain.wiki/wiki/utxo-model-and-bitcoin-transactions.md) — transaction-graph foundation for Layer 2 - [The peer-to-peer network](https://timechain.wiki/wiki/the-peer-to-peer-network.md) — base-layer gossip-and-propagation - [Network capacity and fee-market critiques](https://timechain.wiki/wiki/network-capacity-and-fee-market-critiques.md) — substantive critique-engagement (cross-listed) - [Lightning Network operational critiques](https://timechain.wiki/wiki/lightning-network-operational-critiques.md) — substantive critique-engagement (cross-listed) - [Lightning privacy properties](https://timechain.wiki/wiki/lightning-privacy-properties.md) — cross-linked from Lightning fundamentals notes - [OP_CAT and the covenants programmability debate](https://timechain.wiki/wiki/op-cat-and-the-covenants-programmability-debate.md) — relevant for Ark and other covenant-dependent Layer-2 - [BIP-300 and the Drivechains debate](https://timechain.wiki/wiki/bip-300-and-the-drivechains-debate.md) — adjacent sidechain debate - [Block Size Wars - History](https://timechain.wiki/wiki/block-size-wars-history.md) — historical context for the off-chain scaling path - [Andreas Antonopoulos](https://timechain.wiki/wiki/andreas-antonopoulos.md) — Lightning technical-reference author - [Pieter Wuille](https://timechain.wiki/wiki/pieter-wuille.md) — SegWit co-author - [Peter Todd](https://timechain.wiki/wiki/peter-todd.md) — RBF, covenant-debate participant - [Greg Maxwell](https://timechain.wiki/wiki/greg-maxwell.md) — foundational protocol primitives - [Jameson Lopp](https://timechain.wiki/wiki/jameson-lopp.md) — operational-practice commentary - [Jimmy Song](https://timechain.wiki/wiki/jimmy-song.md) — Bitcoin developer-educator