Notebooks vs Microservices: Choosing the Right Abstraction

2025-01-20

As teams mature, a familiar question emerges:

“Should this logic live in a notebook, or should we turn it into a microservice?”

The wrong answer is choosing one by default.
The right answer depends on what problem you’re actually solving.

This post explains where notebooks shine, where microservices are necessary, and why forcing one to behave like the other leads to fragile systems.

What Microservices Are Really For

Microservices exist to solve operational problems, not exploratory ones.

They are optimized for:

• Stable, long-running behavior
• Well-defined inputs and outputs
• Clear ownership boundaries
• Independent deployment and scaling
• Predictable failure modes

A microservice is not just “code behind an API”.
It is a contract with the rest of the system.

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