Dependencies, distributed code and engineering velocity

transcript

Dependencies,Distributed codeand engineering velocity

Mike McGarr@SonOfGarr© J. Michael McGarr, 2017

I have a problem...

...that impacts every engineer at Netflix.

Affects you too.

I don't know the solution.

direction

So what is this problem?

SHAREDCODE© J. Michael McGarr, 2017

cloud microservices

client libraries

transitive dependencies

consuming librariesshould beeasy

software isn't static

semantic versions

(*) 3.1.133.1.143.1.153.1.163.2.03.2.13.2.23.2.3

4.0.0-RC1

Which version is good?

(*) 3.1.13 ❌3.1.14 ❌3.1.15 ❌3.1.16 ✔3.2.0 ❌3.2.1 ❌3.2.2 ✔3.2.3 ❌

4.0.0-RC1 ❓

Semantic versioning is insufficient

Which version of guava will you get?

Pinning versions is technical debt

Just give me a version thatworks!

consuming librariesis actuallyhard

Well, at leastpublishing

is the easy, right?© J. Michael McGarr, 2017

Need to change foobar-client:3.2.2→ Bug fix? 3.2.3

→ Behavior change? 3.2.0→ API change? 4.0.0

Who will I break?

Who is consumingmy library?

Who is using thisAPI

that I want to change?© J. Michael McGarr, 2017

Publishers lack

organization-widevisibility

There are solutions out

there...© J. Michael McGarr, 2017

Option #1:

Just deal with pain

Option #2:

Share nothing

Option #2:

Share nothing little

Option #3:

Monorepo

→ all code in a single repository→ source integration→ head is production

→ no versions→ atomic API changes

→ lock step deployments

constraints

monorepo depends on gates

Our approach...© J. Michael McGarr, 2017

Can we get the benefitsof a monorepo,

Publisher feedbackManaged source

Publisher feedback

AstridNiagara

I now know who I will break!

eliminate reduceconsumer pain

Shorten adoption curve

Give me a version thatworks!

Distributed refactoring

Gradle Lint

How do IChange my API

across hundreds of repos?

1. Find all repositories2. Find all API calls

3. Refactor all API calls4. Issue pull requests en masse

experimental

Publisher feedbackManaged source

"Eventually consistent distributed monorepo"-- Avi Bryant (Stripe)

Will this work?

Thank youMike McGarr@SonOfGarr

Dependencies, distributed code and engineering velocity

Technology