Introduction

Welcome to Requiem, a modern plain-text requirements management tool designed for software and systems engineers who value simplicity, speed, and integration with their existing workflows.

What is Requiem?

Requiem (package name: requirements-manager, CLI: req) is a spiritual successor to Doorstop, reimagined for the modern development landscape. It enables teams to:

• Manage requirements as plain text - Store requirements as markdown files with YAML frontmatter, making them human-readable, version-controllable, and diff-friendly
• Build traceable requirement hierarchies - Link requirements together to form directed acyclic graphs (DAGs) that trace from high-level user needs down to detailed specifications
• Support multiple parents - Unlike many tools, Requiem allows a single requirement to satisfy multiple parent requirements, reflecting real-world complexity
• Integrate seamlessly - Works alongside documentation tools like Sphinx and MdBook, fitting naturally into your existing documentation workflow
• Scale with performance - Built in Rust with parallel processing, Requiem is designed to be much, much faster than its predecessors

When to Use Requirements Management

Requirements management is essential when:

• Traceability is critical - Regulated industries (aerospace, medical devices, automotive) often require proof that each requirement is implemented and tested
• Teams need alignment - Multiple stakeholders (users, developers, testers, managers) need a shared understanding of what's being built
• Systems are complex - Large projects with many interconnected components benefit from formal requirement tracking
• Change management matters - Understanding the impact of requirement changes across dependent systems is crucial
• Documentation must be maintained - Requirements serve as the foundation for design documents, test plans, and user manuals

Project Status

Requiem is in early development and not yet ready for production use. Current status:

Implemented:

• ✅ Manage requirements, specifications, and documents in plain text
• ✅ Create and link requirements with human-readable IDs
• ✅ Support multiple parent relationships
• ✅ Content fingerprinting for change detection
• ✅ Integration with MdBook and Sphinx
• ✅ Parallel loading for performance

Planned:

• 🚧 Detect cycles in requirement graphs
• 🚧 Trigger reviews when dependent requirements change
• 🚧 Generate coverage reports (requirement → implementation → test)
• 🚧 Import and export in standard formats

Contributions are welcome! See the GitHub repository for more information.

Design Philosophy

Requiem is built on several core principles:

1. Plain text first - Requirements are markdown files that can be read, edited, and reviewed without special tools
2. Git-friendly - Every requirement change creates a meaningful diff that's easy to review in pull requests
3. Dual identifiers - Stable UUIDs for machine processing, human-readable IDs (like USR-001) for people
4. Fast by default - Parallel processing and efficient data structures mean Requiem scales to large projects
5. Composable - Works alongside your existing documentation tools rather than replacing them
6. Documentation tool friendly - HRIDs are stored in markdown headings (e.g., # USR-001 Title) for seamless integration with Sphinx and MdBook

Who This Guide Is For

This guide is designed for:

• Requirements engineers managing formal requirement sets
• Technical writers documenting software systems
• Developers working in regulated environments
• Project managers needing traceability and impact analysis
• QA engineers mapping requirements to test cases

You should be comfortable with:

• Command-line tools
• Text editors
• Basic version control (Git)
• Markdown formatting

What's in This Guide

This guide includes:

• User Guide: Learn how to use Requiem effectively
• Reference: Detailed CLI and file format specifications
• Example Project: See Requiem managing its own requirements as a real-world example

The Example Project contains all 21 requirements that define what Requiem does, demonstrating traceability, proper structure, and best practices.

Let's get started!