Proposal: Daml Upgrade Compatibility Linter

[ayushsingh82]

Development Fund Proposal Submission

Proposal file: /proposals/daml-upgrade-compatibility-linter.md

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Summary

An open-source static analysis tool that compares two compiled Daml package versions and reports whether the new version is a safe smart contract upgrade of the old one, pointing to the exact template, field, or choice and the source location of any breaking change. It runs locally and in CI so teams catch upgrade problems before they deploy, and is released under Apache-2.0.

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Checklist

• Proposal file added under /proposals/
• Milestones and funding amounts defined
• Acceptance criteria included
• Alignment with Canton priorities described

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Notes for Reviewers

This follows the design of the already approved Daml Package Analyzer (#130): it reads the compiled artifact and reports source-level findings, but it compares two versions of one package for upgrade safety rather than analyzing cross-package authority. Suggested SIG label: daml-tooling. Seeking a champion from the Daml Language & Developer Tooling SIG. cc @hrischuk-da

[ayushsingh82]

Hi @hrischuk-da, this proposal fits the Daml Language & Developer Tooling SIG. It is a static analysis tool that compares two compiled DAR versions and reports smart-contract-upgrade breakages before deployment, with source-level findings, modeled on the already approved Daml Package Analyzer (#130).

External proposals need a Tech & Ops Committee champion to stay open. Given your work across Daml tooling and DAR package management, would you be open to championing it, or pointing me to the right person? cc @Andrew-Pohl

Happy to adjust scope, milestones, or funding. Thank you.

[github-actions]

@ayushsingh82, your proposal is missing a Special Interest Group (SIG) label. Adding the right SIG label ensures the relevant domain experts can find and review your proposal, Check more about SIGs.

Please add one of the following labels to this PR:

• attestor-pools-daos-multisig
• canton-apis
• canton-protocol-multi-synchronizer
• daml-tooling
• dapp-integration
• dar-app-management
• defi-liquidity
• defi-protocols
• financial-workflows-composability
• global-synchronizer-scaling
• node-deployment-operations
• onchain-governance
• party-portability-data-resilience
• regulatory-compliance
• token-asset-standards
• tokenomics
• wallet-apps

Not sure which one fits? Pick the closest match to your proposal's domain. You can add a label from the right sidebar under "Labels".

[github-actions]

@ayushsingh82, thank you for your interest in the Canton Development Fund!

Your proposal needs a valid Tech & Ops Committee champion organization. The champion field is either empty, contains placeholder text, or names an organization that is not a current Tech & Ops Committee member.

Per CIP-0100, all external proposals require a Tech & Ops Committee champion.

Next steps:

1. Identify a Tech & Ops Committee member organization willing to champion your proposal
2. Update the Champion field with their name
3. Reopen this PR

If you need help finding a champion, reach out to SIGs or any Tech & Ops Committee member.

This PR is being closed automatically. You are welcome to reopen it once a champion is confirmed.