Design Implementation

Design & Implementation

This skill guides you through the Design and Implementation Engineering phase of the ECSS software development pipeline.

Purpose

This phase involves detailed design of software items, coding, unit testing, and integration. It transforms the technical specification and architecture into working, tested software while managing technical budgets.

Key Activities

• Detailed design: Create low-level design for each software component
• Coding: Implement algorithms and software components according to design
• Unit testing: Verify each software unit independently
• Integration: Combine tested units into larger components
• Manage technical budgets: Monitor memory usage and PU (Processing Unit) load

Technical Budget Management

Critical activities for space systems:

• Memory budget: Track code, data, and stack memory usage against allocation
• PU load budget: Monitor CPU utilization against worst-case execution time allocations
• Budget reconciliation: Verify measured values against predicted values

V&V Focus

Verification and validation activities in this phase focus on:

• Verification of detailed design against technical specification
• Verification of code implementation against design
• Verification of unit test results
• Verification of integration results
• Validation activities against technical specification

Milestone: CDR (Critical Design Review)

The CDR is the gate to the validation and qualification phase. Before CDR approval, ensure:

• Detailed design is complete and documented
• Code listings are available and reviewed
• Unit testing is complete and documented
• Integration testing is complete and documented
• Technical budgets are within allocated limits
• Validation against technical specification has been conducted
• All algorithms are correctly implemented

Inputs & Outputs

| Inputs | Outputs | |--------|---------| | Technical specification | Detailed design documents | | Software architecture | Source code listings | | Component definitions | Unit test results | | SVerP (Software Verification Plan) | Integration test results | | Performance budgets | Budget measurement reports | | | Code reviews |

Checklist

• [ ] Detailed design for all software items completed
• [ ] Detailed design verified against technical specification
• [ ] Code implementation completed
• [ ] Code reviewed for compliance and quality
• [ ] Unit tests written and executed
• [ ] Unit test results verified
• [ ] Integration completed
• [ ] Integration tests executed and passed
• [ ] Memory budget measured and within limits
• [ ] PU load budget measured and within limits
• [ ] Algorithms verified for correctness
• [ ] Validation activities against technical spec conducted
• [ ] CDR package prepared and reviewed

Related Phases

• Previous: Software Requirements & Architecture (invoke /sw-requirements-architecture)
• Next: Validation & Qualification (invoke /validation-qualification)

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: krkruk
• Source: krkruk/openspec-vibe-with-esa-touch
• License: MIT

Install and usage instructions live in the source repository linked above.