Replay Engine

Reconstructing state and instrumenting execution.

The Replay Engine powers Tier 2 and Tier 3 diagnostics.

Historical State

It uses the History Archive Client to fetch compressed ledger snapshots. These are decompressed and loaded into a local state database.

Instrumented Sandbox

Prism uses a modified soroban-env-host that:

• Emits a trace event for every host function call.
• Records gas/budget consumption at each step.
• Captures event emissions and storage diffs.

Execution Timeline

As events are emitted, the engine assembles them into a hierarchical tree representing the full invocation chain.