BAC-L2-TIA-113Celestia and modular blockchains
Building a sovereign rollup III — sync and fork choice
Ensuring anyone can rebuild the same chain from the published data — the operational definition of sovereignty.
- Level
- L2 — Appchain developer
- Duration
- 4 h
- Maintainer
- Modular Blockchain / Celestia Architect
Learning objectives
- 01Implement node synchronisation from the data layer
- 02Define and enforce an explicit fork-choice rule
- 03Demonstrate convergence between two independent nodes
Guided lab
Sync a second node from scratch and verify the resulting states are identical.
Independent lab
Publish two competing blocks at the same height and show fork choice resolves identically everywhere.
Security angle
An ambiguous fork-choice rule produces two equally legitimate chains: the ambiguity is the flaw.
Assessment
Convergence demonstrated between nodes operated by different teams.