Why Microservices maturity model? - Purpose & Use Cases

The Big Idea

What if you could change one part of your app without risking the whole thing breaking?

The Scenario

Imagine a company trying to build a big app by writing all features in one huge program. Every time they want to add or fix something, they must touch the entire code. It's like trying to fix a giant tangled ball of yarn without breaking it.

The Problem

This all-in-one approach is slow and risky. One small change can break many parts. Teams wait for each other, causing delays. It's hard to find bugs or improve performance. The app grows messy and hard to manage.

The Solution

The Microservices maturity model guides teams step-by-step to break the big app into smaller, independent pieces. Each piece does one job well and can be built, tested, and updated alone. This makes the system faster to change, easier to understand, and more reliable.

Before vs After

✗ Before

function processOrder(order) {
  // all logic in one place
  validate(order);
  chargePayment(order);
  updateInventory(order);
  sendNotification(order);
}

✓ After

service OrderValidation { validate(order) }
service Payment { charge(order) }
service Inventory { update(order) }
service Notification { send(order) }

What It Enables

It enables teams to build, deploy, and scale parts of the system independently, speeding up innovation and reducing risks.

Real Life Example

Think of an online store where the payment system can be updated without touching the product catalog or shipping services, allowing faster fixes and new features.

Key Takeaways

Monolithic apps become hard to manage as they grow.

The maturity model helps break apps into manageable microservices.

This leads to faster, safer, and more flexible software development.

Practice

1. What is the primary focus of the first level in the Microservices maturity model?

easy

A. Implementing service discovery

B. Adding automated deployment pipelines

C. Breaking a monolith into independent services

D. Ensuring fault tolerance and resilience

Solution

1. Step 1: Understand the initial maturity level goal

   The first level focuses on decomposing a large monolithic application into smaller, independent microservices.

2. Step 2: Identify what is NOT part of the first level

   Service discovery, automation, and resilience come in later levels, not the first.

3. Final Answer:

   Breaking a monolith into independent services -> Option C

4. Quick Check:

   Level 1 = Decomposition [OK]

Hint: First level means splitting monolith, not automation or resilience [OK]

Common Mistakes:

• Confusing service discovery as first step
• Thinking automation is in the first level
• Assuming resilience is the initial focus

2. Which of the following is the correct syntax to describe the second level in the Microservices maturity model?

easy

A. Services register and discover each other dynamically

B. Services are deployed manually without automation

C. Services communicate synchronously without discovery

D. Services handle failures with retries and circuit breakers

Solution

1. Step 1: Recall the second level feature

   The second level introduces dynamic service registration and discovery to enable services to find each other.

2. Step 2: Eliminate incorrect options

   Synchronous communication without discovery is level 1; manual deployment is level 2 or earlier; failure handling is a later level.

3. Final Answer:

   Services register and discover each other dynamically -> Option A

4. Quick Check:

   Level 2 = Service discovery [OK]

Hint: Level 2 means dynamic discovery, not manual or failure handling [OK]

Common Mistakes:

• Mixing synchronous communication with discovery
• Confusing automation with discovery
• Assuming failure handling is level 2

3. Given a microservices system at maturity level 3, which of the following behaviors would you expect when a service fails?

medium

A. The service automatically retries and uses circuit breakers

B. The system crashes because there is no failure handling

C. Services communicate only via direct IP addresses

D. Deployment is done manually without pipelines

Solution

1. Step 1: Identify level 3 features

   Level 3 focuses on resilience, including retries and circuit breakers to handle failures gracefully.

2. Step 2: Check other options for mismatch

   System crashing means no resilience (level 1 or 2); direct IP communication is basic; manual deployment is unrelated to failure handling.

3. Final Answer:

   The service automatically retries and uses circuit breakers -> Option A

4. Quick Check:

   Level 3 = Resilience with retries [OK]

Hint: Level 3 means automatic failure handling, not crashes or manual steps [OK]

Common Mistakes:

• Assuming no failure handling at level 3
• Confusing communication methods with failure handling
• Ignoring automation in deployment

4. A team claims their microservices system is at maturity level 4 but they still deploy services manually and have no automated rollback. What is the main issue here?

medium

A. They have no failure handling or retries

B. They are missing automation and continuous delivery features

C. They do not have independent services

D. They lack service discovery mechanisms

Solution

1. Step 1: Understand level 4 requirements

   Level 4 focuses on automation, continuous integration, and continuous delivery including automated rollback.

2. Step 2: Identify missing features in the claim

   Manual deployment and no rollback means automation is missing, which contradicts level 4 maturity.

3. Final Answer:

   They are missing automation and continuous delivery features -> Option B

4. Quick Check:

   Level 4 = Automation & CI/CD [OK]

Hint: Level 4 requires automation; manual deploy means not level 4 [OK]

Common Mistakes:

• Confusing service discovery with automation
• Thinking independent services imply automation
• Ignoring rollback as part of automation

5. A company wants to improve their microservices maturity from level 2 to level 4. Which combination of changes should they prioritize?

hard

A. Focus on database scaling and ignore service communication

B. Break monolith into services, add manual deployment, and use direct IP communication

C. Implement retries and circuit breakers only, without automation or discovery

D. Add dynamic service discovery, implement automated deployment pipelines, and introduce failure handling

Solution

1. Step 1: Identify level 2 and level 4 features

   Level 2 includes dynamic service discovery; level 3 introduces failure handling; level 4 adds automation like deployment pipelines.

2. Step 2: Match changes to maturity levels

   Add dynamic service discovery, implement automated deployment pipelines, and introduce failure handling includes discovery (level 2), failure handling (level 3), and automation (level 4), covering needed improvements.

3. Step 3: Eliminate incorrect options

   Break monolith into services, add manual deployment, and use direct IP communication lacks automation and discovery; Implement retries and circuit breakers only, without automation or discovery misses automation; Focus on database scaling and ignore service communication ignores communication and automation.

4. Final Answer:

   Add dynamic service discovery, implement automated deployment pipelines, and introduce failure handling -> Option D

5. Quick Check:

   Level 2 to 4 = Discovery + Automation + Resilience [OK]

Hint: Level 4 needs automation plus discovery and failure handling [OK]

Common Mistakes:

• Ignoring automation when moving to level 4
• Thinking only retries are enough
• Focusing on unrelated scaling aspects