How to determine whether a product requires microservice or monolithic architecture for around 1000 users?

The choice between microservices and monolithic architecture depends on several factors, especially for a product with approximately 1000 users.

Monolithic architecture is usually simpler to develop and deploy, suitable for small teams and projects with limited scaling requirements. If the product does not involve complex business logic, frequent changes, or scaling in different directions, a monolith will be a more rational choice.

Microservices are justified when:

• Independent scaling of individual components is required.
• The team is large enough and divided by functional areas.
• There is a need to use different technologies for different services.
• High fault tolerance and independent service updates are required.

For a product with ~1000 users, if the load and scaling requirements are not high, it is better to start with a monolith. As the product and team grow, microservices can be gradually separated.

Thus, the decision should be made based on current and projected requirements, team resources, and product complexity.