Layer 2 and Rollups: Architecture, Bridges and Building on L2s

About this course

Ethereum’s Layer 2 ecosystem is where most applications will scale. But L2s are not all the same—and choosing the wrong one, or building without understanding sequencers, data availability, and bridges, can cost you millions.

This course teaches you the architecture of optimistic and zero-knowledge rollups, how sequencers work and why decentralization matters, why data availability is the new bottleneck, how bridges fail and how to use them safely, and how to deploy and optimize on Arbitrum, Base, and OP Stack chains.

You’ll work through real examples: analyzing rollup economics, building a ZK circuit, designing a bridge strategy, and deploying a contract to production. By the end, you’ll be able to evaluate any L2, understand its trade-offs, and architect systems that work across multiple chains.

**Who this is for:**
– Blockchain developers building scalable applications
– Protocol engineers evaluating L2 solutions
– Architects designing multi-chain systems
– Teams migrating from Ethereum mainnet to L2

**What you’ll learn:**
– Why Layer 2s exist and the scalability trilemma
– How optimistic and ZK rollups work, and when to use each
– Sequencer design, MEV, and decentralization
– Data availability solutions and their costs
– Bridge mechanics and failure modes
– How to deploy on Arbitrum, Base, and OP Stack
– Gas optimization and UX on L2s
– How to choose the right L2 for your project

**Includes:**
– 7 modules, 24+ lessons with hands-on labs
– Interactive quizzes and knowledge checks
– Capstone project: design an L2 strategy for a protocol
– Shareable certificate of completion
– Lifetime access to course materials and updates

Learn at your own pace. Most learners complete this course in 8–12 weeks.