Aquaculture Water Quality Monitoring System

Senior Ruby/Rails Developer Assessment

Time approximation: 1 hour
Focus: Design patterns, code quality, testing, domain modeling

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📦 What's in This Package

1. ASSIGNMENT.md - The task description and requirements
2. acceptance_tests_spec.rb - Automated tests to validate your solution
3. sensor_data_generator.rb - Generates realistic test data
4. TESTING_INSTRUCTIONS.md - How to use the tests and validate your work

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🚀 Quick Start

1. Install Dependencies

# Install RSpec and other gems
bundle install

2. Read the Assignment

# Start here to understand what you're building
open ASSIGNMENT.md

3. Generate Test Data

# Create realistic sensor reading scenarios
ruby sensor_data_generator.rb

This creates:

• sensor_test_data.json - All test scenarios
• sensor_data_*.csv - Individual scenario files

4. Implement Your Solution

Create your implementation following this interface:

# Required classes:
class SensorReading
  attr_reader :temperature, :ph, :dissolved_oxygen
  def initialize(temperature:, ph:, dissolved_oxygen:)
end

class SalmonProfile
  def thresholds  # Returns hash with min/max values
end

class TilapiaProfile
  def thresholds  # Returns hash with min/max values
end

class WaterQualityChecker
  def initialize(species_profile)
  def check(reading)  # Returns array of alert strings
end

5. Validate Your Solution

# Run the acceptance tests
bundle exec rspec acceptance_tests_spec.rb

Goal: All 48 tests should pass ✅

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📋 Deliverables

Please submit:

1. Your Implementation (Ruby files)

   • Main classes (SensorReading, Profiles, Checker)
   • Well-organized, readable code
   • Use appropriate design patterns

2. Your Tests (RSpec files)

   • Unit tests for your classes
   • Test coverage for main scenarios
   • Include edge cases

3. Documentation (README or comments)

   • How to run your code
   • Design decisions and patterns used
   • How to add new species

4. Proof of Passing (optional but recommended)

   • Screenshot or output of passing acceptance tests
   • Shows all 48 examples passing

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✅ Success Criteria

Your solution should:

• ✅ Pass all 48 automated acceptance tests
• ✅ Use appropriate design patterns (Strategy recommended)
• ✅ Be easy to extend (add new species, parameters)
• ✅ Have clean, readable Ruby code
• ✅ Include your own comprehensive tests
• ✅ Be well-documented

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🎯 What We're Evaluating

1. Design Patterns (30%) - Appropriate use of Strategy, Factory, etc.
2. Code Quality (25%) - Readability, Ruby idioms, maintainability
3. Testing (20%) - Your tests + passing acceptance tests
4. Domain Modeling (15%) - Understanding aquaculture concepts
5. Documentation (10%) - Clear explanations of decisions

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⏱️ Time Management Tips

• 10 min - Design and planning (sketch classes)
• 30 min - Core implementation
• 15 min - Write your tests
• 5 min - Documentation and final validation

Pro tip: Make sure acceptance tests pass BEFORE writing documentation!

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💡 Hints

• Start simple - get basic validation working first
• Use the Strategy pattern for species profiles
• Make sure check() returns an array (not nil)
• Alert messages should be descriptive
• Run tests frequently to catch issues early

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📞 Questions?

If you have questions about:

• Requirements: Check ASSIGNMENT.md
• Testing: Check TESTING_INSTRUCTIONS.md
• Interface: Look at acceptance_tests_spec.rb examples

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📤 Submission via GitHub

Share the repository link

• If private repo: Add us as collaborator
• If public repo: Just send us the link

Repository Checklist

• All implementation files committed
• Your own tests included
• README with setup instructions
• Proof that acceptance tests pass (screenshot or CI)
• Clean git history (meaningful commits)
• Repository link shared with us

Submit by sharing: Your GitHub repository URL

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Good luck! 🐟🦐

We're excited to see your solution!