RFC: Canton Bindings — multi-language SDKs + JWT/OIDC + pre-flight profiler

## Development Fund Proposal Submission **Proposal file:** `/proposals/2026-0…5-HackTourIndia-canton-bindings.md` --- ## Summary Canton Bindings delivers production-grade Java/Kotlin and Rust client SDKs for the Canton Network, a polyglot JWT/OIDC authentication toolkit with first-class presets for Keycloak, Auth0, Azure AD, and Okta, and a pre-flight transaction byte-size and Canton Coin cost profiler. The scope is targeted at the institutional Java/Kotlin developer cohort — the same JVM-heavy teams behind DTCC, Goldman, HSBC, BNY Mellon, and Broadridge — and the high-performance Rust services cohort adjacent to it. Scope was deliberately narrowed after reviewing every open and merged proposal in this repository. We do not propose TypeScript (covered by DA's dApp SDK proposal), Go (covered by Noders LLC's go-daml and go-wallet-daml), Python (DAZL exists; Noders is upstreaming improvements), or C#/.NET (covered by Peaceful Studio). The scope is the empty quadrant of the Canton language matrix. Total requested funding: **850,000 CC fixed + up to 150,000 CC adoption-tied bonus** across 4 milestones over approximately 36 weeks. Fixed and adoption-tied portions are evaluated independently. --- ## Checklist - [x] Proposal file added under `/proposals/` - [x] Milestones and funding amounts defined - [x] Acceptance criteria included (delivery-based for M1-M3 and M4 fixed; adoption-based for M4 bonus) - [x] Alignment with Canton priorities described - [x] Security considerations addressed via a dedicated audit milestone (M3) per pre-PR guidance from @Jatinp26 - [x] Relationship to in-flight proposals explicitly documented (Section 2) --- ## Pre-PR community engagement - Canton Network Forum RFC: https://forum.canton.network/t/rfc-canton-bindings-multi-language-sdks-jwt-oidc-pre-flight-profiler/8668 - grants-discuss mailing list thread: https://lists.sync.global/g/grants-discuss/topic/rfc_canton_bindings/119439952 - Direction to proceed received from @Jatinp26 on the forum thread, with explicit commitment to daml-tooling SIG review and security review. - Full design document and architecture diagrams: https://github.com/jatinsahijwani/canton-bindings --- ## Notes for Reviewers Particularly interested in input from: 1. **Daml Language & Developer Tooling SIG** (@nycnewman, @v9n, @srikanth-bitdynamics, @Andrew-Pohl, @LimKianAn) — on the codegen IR design and the JVM/Rust emitter strategy 2. **DAR Package Management & App Lifecycle SIG** (@nycnewman, @zheli, @akshaysinha100) — on the Package ID Resolver semantics, especially participant introspection vs. baked metadata 3. **Canton APIs SIG** (@mgaare, @akashgaurav) — on the gRPC Ledger API + JSON API integration surface for the JVM and Rust runtimes cc @Jatinp26 : PR opened per your direction on forum thread 8668. Scope was refined down from the original 5-language RFC after reading the full proposals directory, as flagged on the forum thread earlier today.

## Development Fund Proposal Submission **Proposal file:** `/proposals/2026-0…5-HackTourIndia-canton-bindings.md` --- ## Summary Canton Bindings delivers production-grade Java/Kotlin and Rust client SDKs for the Canton Network, a polyglot JWT/OIDC authentication toolkit with first-class presets for Keycloak, Auth0, Azure AD, and Okta, and a pre-flight transaction byte-size and Canton Coin cost profiler. The scope is targeted at the institutional Java/Kotlin developer cohort — the same JVM-heavy teams behind DTCC, Goldman, HSBC, BNY Mellon, and Broadridge — and the high-performance Rust services cohort adjacent to it. Scope was deliberately narrowed after reviewing every open and merged proposal in this repository. We do not propose TypeScript (covered by DA's dApp SDK proposal), Go (covered by Noders LLC's go-daml and go-wallet-daml), Python (DAZL exists; Noders is upstreaming improvements), or C#/.NET (covered by Peaceful Studio). The scope is the empty quadrant of the Canton language matrix. Total requested funding: **850,000 CC fixed + up to 150,000 CC adoption-tied bonus** across 4 milestones over approximately 36 weeks. Fixed and adoption-tied portions are evaluated independently. --- ## Checklist - [x] Proposal file added under `/proposals/` - [x] Milestones and funding amounts defined - [x] Acceptance criteria included (delivery-based for M1-M3 and M4 fixed; adoption-based for M4 bonus) - [x] Alignment with Canton priorities described - [x] Security considerations addressed via a dedicated audit milestone (M3) per pre-PR guidance from @Jatinp26 - [x] Relationship to in-flight proposals explicitly documented (Section 2) --- ## Pre-PR community engagement - Canton Network Forum RFC: https://forum.canton.network/t/rfc-canton-bindings-multi-language-sdks-jwt-oidc-pre-flight-profiler/8668 - grants-discuss mailing list thread: https://lists.sync.global/g/grants-discuss/topic/rfc_canton_bindings/119439952 - Direction to proceed received from @Jatinp26 on the forum thread, with explicit commitment to daml-tooling SIG review and security review. - Full design document and architecture diagrams: https://github.com/jatinsahijwani/canton-bindings --- ## Notes for Reviewers Particularly interested in input from: 1. **Daml Language & Developer Tooling SIG** (@nycnewman, @v9n, @srikanth-bitdynamics, @Andrew-Pohl, @LimKianAn) — on the codegen IR design and the JVM/Rust emitter strategy 2. **DAR Package Management & App Lifecycle SIG** (@nycnewman, @zheli, @akshaysinha100) — on the Package ID Resolver semantics, especially participant introspection vs. baked metadata 3. **Canton APIs SIG** (@mgaare, @akashgaurav) — on the gRPC Ledger API + JSON API integration surface for the JVM and Rust runtimes cc @Jatinp26 : PR opened per your direction on forum thread 8668. Scope was refined down from the original 5-language RFC after reading the full proposals directory, as flagged on the forum thread earlier today.