# Blocked by the backend? Use prod mocks.

March 29th, 2022 | 13:08 | E84

### Episode Summary

In this episode Sandeep and Alex showcase how mocks can be used in production code to substitute upcoming unfinished or unreleased backend changes. They use dependency injection and Liskov Substitution Principle to inject a service object implementation that uses local hardcoded data instead of fetching it from the network.

### Episode Notes

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Show Contributors

Alex Bush

Sandeep Aggarwal