fine-tuning of agile development

FINE-TUNING OF AGILE DEVELOPMENT

Isa Goksu, Cengiz Han

C o n t i n u o u s D e l i v e r y i n P r a c t i c e

ABOUT US

§  Isa Goksu, @IsaGoksu Tech Principal

§  Cengiz Han, @hancengiz Tech Lead

2 © 2014 ThoughtWorks, Inc. All rights reserved.

RECOGNIZE THIS?

§  Single line of change takes a week to deploy

§  Slow Feedback (10 weeks after delivering the features, receiving your first feedbacks)

§  You started a new project, defect from old project is bugging you

§  Code Freeze?

§  Sleepless nights during deployments


“How long would it take your organization to deploy a change that involves just one single line of code?”

Mary and Tom Poppendieck


THE CONTINUOUS DELIVERY MATURITY MODEL


Where to start?


1

7

make it always production ready

© 2014 ThoughtWorks, Inc. All rights reserved.

TRUNK-BASED DEVELOPMENT

8

§  One and only one branch

§  Continuously Integrate with the team

§  All the time production ready

§  At least 1-commit per day per pair/dev

§  Quality increase

FEATURE TOGGLING

§  Helps you to have production-ready code all the time

§  Gives you the flexibility of trying out multiple features

§  QA can test individual features or group of features

§  Business can get fast feedback thru feature previewing


10

Features developed in an iteration

Enabled features in production


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Many more..

C# - FeatureSwitcher

Golang - flag

Python - Waffle

Ruby - Feature-Toggles

Node.js - feature-flags


FEATURE BRANCHING

§  Avoid it! §  CI is a problem

§  Long-lived

§  Merging hell

§  Works on §  Small teams

§  Short-lived


2

13

build quality in


TEST STRATEGY

§  Make the QA the key participant of your flow

§  QAs are not just testers (assuring quality)

§  Enforces you to deliver vertical slices

§  Consider using new approaches like Specification by Example, Generative Testing, Parametric Testing)

§  Automation is a must


3

17

keep everything in source control


STORING DB CHANGES IN SCM

§  Start with a clean DB

§  Use proven tools (dbdeploy, liquidbase, etc)

§  Make sure deltas are incremental, small and immutable

§  Have rollback scripts ready and auto rollback if possible, or do only roll-forward

§  Fail directly if any delta fails

§  Run each delta in order

§  Stored together 18 © 2014 ThoughtWorks, Inc. All rights reserved.

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DBDeploy Metadata

Baseline Database

Apply Deltas

Test

Fail Fast

Apply Deltas Apply Deltas

Apply Deltas Apply Deltas


INFRASTRUCTURE AS CODE

§  Determinism vs. Indeterminism

§  Treat your infrastructure as you are coding

§  Helps you to have system consistency

§  Use proven tools (puppet, chef, ansible, bcm, cfengine, etc)

§  Have a test machine/vm to try 21 © 2014 ThoughtWorks, Inc. All rights reserved.

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System Config.

SCM Puppetmaster

WebServers AppServers OtherServers WebServers AppServers OtherServers


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Puppet example manifest for

Apache HTTP server


TEST IT BEFORE GET IT OUT


4

25

repeatable, risk-free deployments


UNIFIED WAY

§  Build one binary and use it everywhere

§  Deploy the same way to all environments

§  Unattended deployments

§  Separate the things that change from the thing that don’t


VIRTUALIZATION

§  Use one

§  Containers vs Hypervisors

§  Availability, Fail-safe

§  Fast provisioning

§  You can automate it!


PACKAGING

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RPM | CHOCOLATEY

sudo rpm –ivh awesome-app-1.0.rpm Cinst awesome-app –version 1.0


5

29

everybody is responsible


MTBF, MTRS

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§  Failure is inescapable just like getting sick §  Self-healing systems (auto-scale, retries, etc)


IMMUNE SYSTEMS

§  Zero access policy (phoenix or immutable servers)

§  Monitoring (graphite, riemann, munin, nagios, etc)

§  Logging (ELK clusters, Graylog2, syslog, etc)

§  Application Status / Healthcheck / Configuration Endpoints


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Status Endpoint Healthcheck Endpoint

GET http://my.service/status

GET http://my.service/healthcheck


SUMMARY

§  DONE means released!

§  Automate everything

§  Be always production ready

§  If anything fails, stop the delivery line

§  Keep everything in SCM

§  Build binaries only once

§  Use precisely the same mechanism to the every environment


Q/A Ping us later @IsaGoksu, @hancengiz


fine-tuning of agile development

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