Snake

Overview

Classic Snake game implemented as a single self-contained HTML file. Grid-based gameplay with arrow key controls, collision detection, and food spawning. Built with strict error handling and an included test suite using Vitest. No external runtime dependencies.

Zone: staging/ — under evaluation, not yet promoted to apps/.

Related game projects: chess, cards-and-games

Tech Stack

Component	Technology
Language	Vanilla JavaScript
Rendering	Canvas 2D API
Testing	Vitest 2.x
CI/CD	GitHub Actions (security.yml)
Entry Point	snake_v1.1.0.html (single file)

No external runtime dependencies. Vitest is the only dev dependency.

Architecture

The entire game lives in snake_v1.1.0.html — a single self-contained file. No build step, no bundler.

Key implementation details:

• 400x400 canvas with 20px grid cells (20x20 grid)
• 150ms fixed movement interval
• safeRun() wrapper for error recovery and safe fallback rendering
• Type validation for segment and food coordinates
• Arrow key controls with 180-degree reversal prevention

Collision Detection

Three collision types handled:

1. Boundary collision — snake head exits the 400x400 canvas grid
2. Self-collision — head overlaps any existing body segment
3. Food consumption — head occupies food cell (score increment, new food spawned)

Testing

Built-in test harness (separate from src/ + tests/ structure using Vitest). Tests cover:

• Collision scenarios
• Food boundary validation
• Mock data injection for reproducible runs

Run tests: npm test (executes vitest run)

Current Status

Zone: staging — Phase 2 compliance deployed on 2026-03-13

Compliance checklist:

• security.yml — TruffleHog + Trivy + Semgrep (calibration mode through 2026-04-13)
• SECURITY.md — Vulnerability reporting
• .github/PULL_REQUEST_TEMPLATE.md
• .github/CODEOWNERS
• .security-config.yml

Pending gaps:

• Test coverage below 60% target
• General CI/CD lint+test pipeline not yet configured
• No pause/resume functionality
• No high score persistence — score and game state reset on page refresh
• No mobile/touch controls (keyboard only)

Known Limitations

Per README: no pause/resume, no difficulty scaling, no audio, no high score tracking, no mobile controls, no customizable colors. Fixed grid size and movement interval (150ms).

Lessons Learned

• Calibration mode for new staging repos: All new staging repos start security CI in calibration mode to establish a baseline before switching to enforcing mode. See 3-scanner-security-architecture.
• Single-file architecture is valid for small games: A self-contained HTML file eliminates build complexity for a proof-of-concept. Tradeoff is harder to test individual modules — the src/ + Vitest structure addresses this separately.