Maersk Lead Engineer Interview Questions and Answers

Circuit breaker pattern is a design pattern used in cloud platforms to prevent cascading failures.

• It is used to detect failures and prevent them from causing further damage

• It works by temporarily blocking requests to a service that is experiencing issues

• Once the service is back up, the circuit breaker allows requests to resume

• Examples include Netflix's Hystrix and AWS's Circuit Breaker

Azure Functions is a serverless compute service that enables you to run event-triggered code without having to manage infrastructure.

• Azure Functions can be used to build serverless applications and microservices.

• It supports multiple programming languages such as C#, Java, JavaScript, Python, and PowerShell.

• Limitations include a maximum execution time of 10 minutes, limited memory and CPU resources, and a cold start del...read more

Azure functions are event-driven, serverless compute solutions while worker processes are long-running processes.

• Azure functions are triggered by events such as HTTP requests, messages in a queue, or changes in a database.

• Worker processes are long-running processes that perform a specific task continuously.

• Azure functions are serverless, meaning that the infrastructure is managed by Azure.

• Worker processes require a ser...read more

Abstract classes are used to provide a common interface for its subclasses.

• Abstract classes cannot be instantiated, only extended.

• They can contain abstract and non-abstract methods.

• They are useful for creating a hierarchy of classes with shared methods and properties.

• They can also be used to enforce certain behaviors in subclasses.

• Example: Animal is an abstract class with abstract methods like eat() and non-abstract me...read more

Throttling is the process of limiting the amount of data or requests that can be sent or received within a certain period of time.

• Throttling is used to prevent overload on servers or networks.

• It can be implemented through software or hardware.

• Examples include API rate limiting and internet service providers limiting bandwidth.

• Throttling can also be used to intentionally slow down certain processes or devices to conserv...read more

Service discovery is the process of automatically locating services in a network. Azure provides Azure Service Fabric for service discovery.

• Service discovery helps in locating services in a network without hardcoding their addresses.

• Azure Service Fabric provides a built-in service discovery mechanism.

• Service Fabric uses naming conventions and DNS resolution to discover services.

• Service Fabric also provides APIs for ser...read more

Ambassador pattern is a Kubernetes design pattern that allows for external access to services.

• It involves using a sidecar container to proxy requests from outside the cluster to the service.

• The sidecar container can handle tasks such as authentication and load balancing.

• It allows for decoupling of the service from the external access mechanism.

• Examples include the use of Ambassador and Istio as implementations of the p...read more

MongoDB supports various data design patterns for record references.

• MongoDB supports embedding documents within other documents.

• MongoDB also supports referencing documents from other collections.

• The choice between embedding and referencing depends on the data access patterns.

• Embedding is preferred for one-to-one and one-to-many relationships.

• Referencing is preferred for many-to-many relationships.

• MongoDB also supports ...read more

Microservices utilize various data storage patterns like per service DB, shared DB, SAGA, and event sourcing for effective data management.

• Per Service DB: Each microservice has its own database, promoting loose coupling. Example: User service with its own user database.

• Shared DB: Multiple services share a single database, which can lead to tight coupling. Example: Both Order and Payment services using the same database...read more