lib-constant-time

lib-constant-time provides shared constant time primitives and contracts used by EriX components.

EriX is a clean-room, capability-based microkernel operating system written entirely in Rust.

Technical requirements are tracked in the EriX requirements, conventions, and project documentation.

See:

• docs for design documents, specifications, and development plans.
• Related architecture repositories for kernel, services, libraries, drivers, and integration tooling.

Purpose of This Repository

This repository implements the EriX constant-time library. Its purpose in EriX is to provide reusable constant-time primitives and contracts to EriX components.

Functionally, it exposes the constant-time APIs, validation tests, and documentation used by dependent repositories. The repository keeps the implementation, interface contracts, tests, and documentation for that behavior in one reviewable ownership boundary.

The maintained responsibilities are:

• expose the lib-constant-time crate API for constant-time behavior used by dependent components
• keep data formats, constants, and validation helpers documented and tested
• preserve clean-room, no-external-crate implementation boundaries
• maintain compatibility expectations for downstream repositories

Clean-Room Policy

EriX follows a strict clean-room philosophy:

• No external source code may be copied.
• No external Rust crates are allowed.
• No code generation tools that embed third-party code.
• All code must be authored within the project.

Violations will result in rejection of the contribution.

License

All EriX repositories are licensed under the ISC License.

Development Model

EriX development is modular, deterministic, reproducible, authority-explicit, security-first, and self-hosting oriented.

This repository follows the project roadmap and the validation rules documented in its own roadmap.

Status

Implemented baseline.

Core constant-time primitives are implemented with unit coverage. Remaining work focuses on hardening-oriented review and expanded downstream integration checks.

See ARCHITECTURE.md and ROADMAP.md.

Governance Principles

lib-constant-time governance is scoped to reusable constant-time contracts shared by dependent repositories.

The scoped governance rules are:

• It must expose narrow, documented APIs rather than component-specific policy.
• It keeps wire formats, constants, parsers, and validation helpers deterministic and testable.
• It preserves clean-room implementation boundaries and does not introduce external crate dependencies.
• Breaking API or format changes require coordinated updates in every dependent repository.

Library Boundaries

• lib-constant-time carries no runtime authority by itself; authority is held by callers that use the library.
• The crate must not hide ambient I/O, allocation policy, or service discovery behind helper APIs.

Contact

Development occurs in EriX organization and discussions happen in issues and design documents.

No decisions are considered valid without documented rationale.

Maintainers can be reached via email: admin@erikinkinen.fi.