why should you care about docker?

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lots of smaller services

• bigger operational overhead
• trickier to run locally

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what problems?

(and potential solutions without docker)

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it works on my machine

• you can just get a developer VM
• needs beefy dev machines
• slow startup and big VM images

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configuration managament

• Puppet/Chef/etc has to ensure state is correct
• every single time!

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packaging

• just build a deb/rpm package - fpm
• you know what f stands for, right?

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docker

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docker vs VMs

• just do an image search
• lightweight, less overhead

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docker images

• union filesystem and caching
• immutable (shareable!) layers
• base images FTW

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docker registry

• docker images to deploy code instead of packages