Which design type is this question?

It is a cloud infrastructure question. You design a container image registry like docker hub and explain your choices the way you would in an interview.

Is this question asked at entry level?

It is marked Easy, so it suits engineers who are new to cloud infrastructure interviews. It is also a good warm-up before harder questions.

What should I cover first?

Start with the workloads, the availability target and the security and cost limits. Agree on scope with the interviewer before you design anything.

Can I practise it for free?

It is a premium question. Sign up and unlock it once for 10 credits; it then stays unlocked. When you finish, Lala, your personalized AI mentor, can review your design for 30 credits.

Design a container image registry like docker hub

PremiumCloud infrastructureEasy

OCI distribution
Content addressable storage
Image layers

Quick answer

This cloud infrastructure interview question asks you to design a container image registry like docker hub. Aim for a design that runs reliably and securely in the cloud at a sensible cost, then explain the services, regions, deployment and trade-offs. Interviewers want to see how you balance reliability, security and cost.

The problem

Design a container image registry like Docker Hub: developers push images and servers pull them by tag or digest. Images are stacks of layers stored once by content hash. The hard parts are huge pull bursts during deploys, large uploads that must resume, and deleting unused layers without breaking images.

An image is a manifest (a small JSON file) that lists a config blob and layer blobs by their sha256 digest. A tag such as app:1.4 is a movable pointer to a manifest digest. A pull fetches the manifest, then downloads only the layers the machine does not already have.

What must a container image registry like docker hub do?

Push: Upload blobs in resumable chunks, verify each digest, then upload the manifest and move the tag.
Pull: Fetch a manifest by tag or digest, then download layers by digest.

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How well must it do it?

Pull speed: Manifest lookups under 100 ms at p99; layers stream at the client's full bandwidth.
Durability: No blob that a manifest references is ever lost.

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What scale should you design for?

Use these numbers in your estimates.

The scale numbers unlock with this questionUnlock

Key concepts

OCI distribution
Content addressable storage
Image layers
CDN
Garbage collection
Pull through cache

How you’ll practise

6 short steps · save and come back any time

Requirements
Environments and topology
Deployment pipeline
Reliability and disaster recovery
Observability and cost
Wrap-up

Lala, personalized to you, gives a hint when you ask and reviews your design when you are ready.

What do interviewers look for?

In any cloud infrastructure design round.

Clarifies availability, security and cost targets
Chooses managed services with reasons
Plans regions, zones and failover
Covers identity, secrets and network boundaries
Explains deployment, rollback and observability
Keeps an eye on cost as usage grows

Questions people ask about this interview question

Which design type is this question?: It is a cloud infrastructure question. You design a container image registry like docker hub and explain your choices the way you would in an interview.
Is this question asked at entry level?: It is marked Easy, so it suits engineers who are new to cloud infrastructure interviews. It is also a good warm-up before harder questions.
What should I cover first?: Start with the workloads, the availability target and the security and cost limits. Agree on scope with the interviewer before you design anything.
Can I practise it for free?: It is a premium question. Sign up and unlock it once for 10 credits; it then stays unlocked. When you finish, Lala, your personalized AI mentor, can review your design for 30 credits.

The problem

What must a container image registry like docker hub do?

How well must it do it?

What scale should you design for?

Key concepts

How you’ll practise

What do interviewers look for?

Questions people ask about this interview question

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