Resolve 330+ Backend Compilation Errors & Establish CI/CD Pipeline

[anonfedora]

Description:
The current Rust backend in backend/ has over 330 compilation errors primarily related to SQLx query verification, type annotations, and ambiguous imports. This issue is a blocker for all other backend development.

Key Tasks:

• Set up a local PostgreSQL instance and run existing migrations in backend/migrations.
• Execute cargo sqlx prepare to generate offline query metadata for all services.
• Resolve ~16 type ambiguity errors in wallet_service.rs and other files by using fully qualified paths or renaming conflicting types.
• Add explicit type annotations for ~113 generic parameter errors throughout the service layer.
• Fix ~30 miscellaneous errors including conflicting trait implementations and mismatched closure signatures.
• Implement a GitHub Actions CI pipeline that runs cargo check and cargo test on every PR.

Acceptance Criteria:

• The backend project compiles successfully with cargo build.
• cargo sqlx prepare is integrated into the build process.
• CI pipeline is green and prevents regressions.

[GazzyLee]

@GazzyLee has applied to work on this issue as part of the Stellar Wave Program's 3rd wave.

Heyy, I’d like to work on this issue.

I have experience working with Rust backends and resolving complex compilation issues, including SQLx query validation, type annotations, and module organization. I can set up the local PostgreSQL environment, run migrations, and generate the required SQLx offline metadata.

I’ll systematically resolve the type ambiguities and generic parameter errors, clean up conflicting implementations, and ensure the codebase compiles successfully. I’ll also set up a CI pipeline to run cargo check and cargo test to prevent future regressions.

Happy to take this on, please assign.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @GazzyLee to this issue.

[drips-wave]

Congratulations, @GazzyLee! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on March 30, 2026.

🧑‍💻 @GazzyLee: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

When opening a PR, please link it to this issue to ensure it gets tracked accurately. Points are awarded when this issue is marked as completed by the maintainer.

🤠 Repo maintainers: Please keep an eye on the contributor's progress and review their work before the due date. You can manage this issue, including adjusting its complexity and points, here.

🌊 Happy Wave 🌊

[khapyinyass]

@khapyinyass has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hi maintainer
I'd love to work on this repo

ℹ️ Repo Maintainers: To accept this application, review their application or assign @khapyinyass to this issue.