The networks are overloaded. Layer 1 cannot handle the load. Layer 2 addresses some issues, but not all. Layer 3 appears as a new architectural attempt — not as a continuation, but as a shift in approach.
What is Layer 3 — without theory
Layer 3 is a framework that does not handle transaction processing directly. It operates on top of Layer 2 and Layer 1, focusing on application logic, routing, privacy, and customization.
Instead of a universal solution — specialized environments:
- for games, where speed and isolation are important
- for DeFi, where flexibility and control over risks are needed
- for identification, where privacy is critical
Where it already works
- zkSync Hyperchains — custom chains based on zk technologies
- Arbitrum Orbit — independent networks with access to Layer 1 security
- Starknet AppChains — isolated environments for applications
- DeFi derivatives — Layer 3 solutions for high-frequency trading
What the developer gets
- A customizable environment for a specific task
- High throughput without overloading the base network
- Isolation: a failure in one application does not affect others
- The ability to integrate with other ecosystems
Where problems begin
- Security: each level adds complexity and increases the attack surface
- Fragmentation: different Layer 3 — different rules, different risks
- Marketing: the term is used as a brand, not as an architectural solution
- Lack of standards: no single approach to consensus, verification, and interaction
Is Layer 3 an architecture?
Not yet. This is an experiment. It is important because it shows where development is heading: from universal solutions to specialized networks.
If standards, tools, and proven cases emerge — Layer 3 can become a new level of engineering maturity.