Design proposals for changes to Astrid's kernel-to-user-space contract.

RFCs govern any substantial change to the contract surface between the kernel and user-space: the host ABI, IPC protocol, capability model, manifest schema, VFS semantics, capsule interface standards, and SDK public API. They are the authoritative specification - implementations conform to them, not the other way around.

• Adding or changing a host function in the syscall table (astrid-sys)
• Changing IPC topic conventions or payload schemas
• Modifying the capability token format or validation semantics
• Changing Capsule.toml manifest schema or dependency resolution
• Changing VFS path resolution rules or overlay behavior
• Defining a new capsule interface standard (tool schemas, cross-capsule contracts)
• Breaking changes to astrid-sdk public API

1. Fork this repo and copy 0000-template.md to text/0000-my-feature.md.
2. Fill in the RFC. Focus on motivation and the reference-level spec.
3. Open a pull request. Use the filename 0000-my-feature.md in the PR.
4. Discussion happens on the PR. Revise as needed.
5. When consensus is reached, a maintainer assigns the next sequential RFC number, renames the file to text/NNNN-my-feature.md, and merges.
6. Implementation proceeds in astrid-sdk (types behind feature flags) and reference capsules.

• Draft - PR open, under discussion.
• Active - Merged. Types being implemented in astrid-sdk.
• Final - Implemented and stable. Breaking changes require a new RFC.
• Withdrawn - Closed without merge.
• Superseded - Replaced by a newer RFC (noted in header).

Each RFC maps to an astrid-sdk feature flag:

# Individual RFC types
astrid-sdk = { version = "0.2", features = ["rfc-1"] }

# All RFC types
astrid-sdk = { version = "0.2", features = ["all-rfcs"] }

Dual-licensed under MIT and Apache 2.0.

Copyright (c) 2025-2026 Joshua J. Bouw and Unicity Labs.