Hiya, I'm Sion (pronounced Shaun) 👋

Engineering leader who ships. Platform builder who scales. Problem solver who automates.

• 🌍 Based in Exeter, UK
• 👨‍👧‍👦 Proud dad of two
• 🔭 Currently exploring: Generative AI, LLMs, and AI Agents
• 💬 Ask me about: DevOps, infra-as-code, GitHub workflows, and pragmatic engineering leadership

What I Do

I lead engineering teams through complex transformations in regulated industries—the kind where "move fast and break things" isn't an option, but velocity still matters.

• Build & lead teams shipping products, infrastructure and platform tooling.
• Design systems that are observable, resilient, and easy to operate.
• Automate repetitive work so engineers can focus on solving real problems.

Featured Projects

🚀 PR Tool

PR Tool

• A command-line tool that fetches GitHub pull requests (PRs) for a specified time period and scope (organization, team, user, or repository), summarises them using an LLM (OpenAI or Ollama), and outputs the result in Markdown format.
• Tech: Go
• Features:
  • Multi-scope PR fetching: Fetch PRs from organizations, teams, users, or specific repositories
  • Time-based filtering: Filter PRs by merge date using relative time ranges (-7d, -1m, -1yr)
  • AI-powered summaries: Generate intelligent summaries using OpenAI or Ollama
  • Multiple output formats: Output to stdout or save to files
  • Flexible configuration: Configure via YAML files, environment variables, or CLI flags
  • CI/CD friendly: Special mode for automated environments
  • Dry-run support: Preview data without generating summaries

🧰 Impact Tree Builder

Impact Tree Builder

• A fully-featured impact tree visualisation tool built with React, TypeScript, Vite, Tailwind CSS, and shadcn-ui.
• Tech: React, TypeScript, Vite, Tailwind CSS, shadcn-ui
• Features:
  • Interactive impact tree visualization with SVG
  • Multiple node types: Business Metrics, Product Metrics, Initiatives
  • Relationship mapping with visual indicators
  • Measurement tracking with performance indicators
  • Canvas controls (zoom, pan, reset, center)
  • Export to JSON, PNG, and HTML

📡 Hierarchical Agent Architecture

HMAS Agents

• The HMAS Agents system uses a hierarchical agent architecture with specialized roles for different aspects of software development.
• Tech: Opencode
• Highlights:
  • Orchestrator: Manages the entire development workflow and delegates tasks to specialized subagents
  • Planner: Breaks down high-level goals into detailed specifications, user stories, and acceptance criteria
  • Architect: Defines technical constraints, selects technologies, and ensures architectural alignment
  • Coder: Implements code based on plans from Planner and Architect
  • Test: Generates and runs tests, performs self-healing for simple failures
  • Debugger: Performs root cause analysis when tests fail
  • Security: Audits code for vulnerabilities and compliance issues

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