I applied online for the Senior Android Engineer role in May-June 2017 in San Francisco, CA. I had a pleasant phone chat with the recruiter at Instacart and a follow-up interview with a lead engineer on the Instacart Android team.

I was asked to implement a simple Android app for the take-home challenge. While I will not reveal the nature of the app out of respect for Instacart, the challenge is required to be finished within approximately 4 hours and is expected to be of production-level quality.

While this should not be challenging under normal situations, the hard time requirements made it very difficult to plan, design, implement, and test the app within the allotted time.

Had it not been for the hard ~4-hour requirement, I would have gladly spent additional hours to implement a proper mobile architecture (MVP/MVVM), as well as unit tests—things that would be expected of a production-ready app.

Some suggestions for Instacart for improving the take-home challenge experience:

• Do not set a hard time requirement; allow candidates some time flexibility to polish their submission. While the core functionality of the challenge can be finished within a few hours, making it a production-ready quality app requires additional time, especially for proper architecture, design, and creating proper tests. Implementing MVP/MVVM/etc. architectures takes a decent amount of time to implement the boilerplate code and should be considered, especially if seeing candidates have experience in implementing mobile architectures.
• Provide UX design documents with the challenge. While many experienced Android developers are able to come up with their own design, coming up with a custom design and implementing it properly still takes time.
• Establish minimum Android API requirements and device expectations. As the challenge did not specify or mention these parameters, it made it somewhat ambiguous about which specific Android API range and device densities to design for and test against.

Please remember, there are thousands of different Android devices with differing Android API versions, and candidates do not have the resources to test against many different device profiles. Not everyone has access to a Nexus 6 or a Samsung Galaxy S3 Mini sitting around to test against.

This will increase the quality of submissions and minimize confusion over expectations of this take-home challenge—a win-win for both Instacart and candidates.

Take-Home Challenge: Implement a simple Android app that meets the challenge specifications.