- L2 for Beginners - describing a mental model of an L2 as a chain which writes enough state back to Ethereum that no one (including the L2's miners/validators) can send back a fraudulent state
- Optimistic rollups vs ZK-rollups - a recent assessment of the state of various rollup projects
- Vitalik's post on rollups - a fairly technical summary of the SOTW of rollups
- Validating Bridges (Sep 2021) - a fairly thorough assessment of L2 solutions (including Oasis?) as well as open research questions
- Eth docs on L2 Rollups - see the bottom of this page for further links
- Almost everything you need to know about optimistic rollups (Jan 2021) - builds up the design for optimistic rollups from first principles, addressing various perceived issues as they arise
- Optimistic rollups: Arbitrum vs Optimism
Primary source of info for zkps should be awesome-zero-knowledge-proofs, a git-based list of learnings curated by Matter Labs.
Our shortlist:
- Validity Proofs vs Fraud Proofs (2019) - StarkWare's summary of fraud proofs (typically employed by optimistic rollups) vs validity proofs (not feasible on optimistic rollups)
- zk-STARKS vs zk-SNARKS
- ethhub ZK-STARKS
- StarkNet (Jan 2021) - StarkWare's description of their STARK-powered zk-rollup
- Awesome StarkNet - curated list of StarkNet resources and tools from @gakonst and others
- zkSync (June 2020) - Matter Labs' description of their "SNORK"-powered zk-rollup. SNORKS are SNARKs with a universal and updateable trusted setup.
- Volitions: best of all worlds (Aug 2021) -
describing the volition, a hybrid system where users can choose between storing their data as a rollup (on-chain
data) or as a validium (off-chain).
- See also StarkWare's proposal (June 2020) for the volition concept, and Matter Labs' description of its volition implementation zkSync 2.0 (Apr 2021)
- Proofs, Arguments, and Zero-Knowledge - extensive survey paper on zero-knowledge argument systems from Justin Thaler
- zkp.science, a compendium of papers and proving systems
- L2beat - comparison of current state of various L2s
- L2 skill tree - this tweetstorm by @likebeckett was instrumental in assembling this page