Opened 28-05-2026 by djolertrk, last activity 4mo ago
Proposal file:
Link to the proposal added in this PR (e.g., /proposals/daml-versioned-debug-info-metadata-draft.md)
This is a placeholder for adding a proposal for rich debug info generation for Daml source.
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Author: Walnut
Status: Early draft / not a funding request
Scope: Future technical proposal
Daml and Canton already expose useful transaction and package data, and LF already carries source span information. That is enough for many forms of inspection and visualization, but richer source-aware tooling needs a stable way to describe how compiled Daml code relates back to source code.
Other mature ecosystems rely on explicit debug metadata formats: DWARF for many native toolchains, PDB/CodeView on Windows, and ETHDebug in the EVM ecosystem. A versioned Daml debug metadata format would give debugger, profiler, coverage, trace, and explorer tools a common target instead of each tool inventing its own mapping.
Define a versioned debug metadata schema for Daml packages.
The first version should build on existing LF span information and focus on metadata that can be emitted by the compiler or as a sidecar artifact:
The format could be embedded in DARs or emitted as a separate artifact. The exact packaging should be decided with Daml/Canton maintainers.
Walnut could help drive the end-to-end workstream:
dpm traceThis matches Walnut's existing work on compiler debug information, source mapping, and blockchain debugging tooling.
damlc versus derived by tools?Rebuilt from the recorded board moves (complete history). get_dev_fund_lifecycle(number) gives the same in the MCP.