June 14, 2015 – Nikola Brežnjak blog

Miscellaneou$

Infobip Dev Days 2015

Here are my notes from an awesome 4th Infobip Dev Days 2015 conference:

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Presenter: Izabel Jelenić, Co-founder, CTO
infobip – 600+ employees (122 devs)
Worldwide A2P SMS traffic is expected to grow. Revenue > 45bn.
They handle 150M transactions daily.
They said they’re doing business with “one big social” network, but they didn’t name it actually, I wonder why is that (some kind of NDA or what? 🙂)
Picture time:

Presenter: Mario Žagar, Senior Software Architect
ASAP and as often we have to go into production
Unit & integration tests
Scaling cube
First they scaled by increasing monoliths
Then they took some parts out of the monolith (API, Billing, Inbound SMS, …) => easier to focus, possible to deploy independently
Typical feature deployment today:
- Short lived feature branches with Git
- Develop & run tests locally
- Push feature branch to remote repository (Stash)
- Jenkins – CI server builds the feature branch
- Deployment artifacts published to Infobip repository (Artifactory)
- Deploy feature branch to integration environment
- Run tests on integration environment
- Merge pull request to master branch & release
Average about 80 deploys per day
DevOps culture – you built it, you deploy it, you support it
Troubleshooting tools:
- Graylog
- Graphite
- Grafana
- Nagios
- Seyren
- HipChat
- Ansible
Picture time:
And a few more here, since, well, you know I love MEMEs:

Presenter: Marko Stipanov, Product Owner
How to increase productivity?
- hiring more devs?
- best is to hire someone new and give them some totally new project
PDD – Panic Driven Development
- the bigger the panic the greater priority
- how relates to this, please hands up
they tried with daily report writing
Agile process manifesto
they divided their 60 devs at a time to 12 teams and each team works on a small project
Product Owner
- vision and definition of products
- goal setting
- priority setting of the whole team
- talks to stakeholders
Scrum ceremonies
- organisation
- iterative process
Scrum steps (they do the sprints fro 1-2 weeks instead of 2-4):
- Product backlog
- Sprint backlog
- SPRINT
- Deliverable
1 project = 1 team
1 team => more projects
Priorities are defined by business value
Kanban, Scrumban
Daily team lead meeting with just few minutes
You can’t do agile without teams!
Scrum definitely give us a better intercommunication.
Picture time:

Presenter: Markus Winand, SQL expert and author
SQL 99 broke the relational standard
- LATERAL
  - “for each” loop of SQL
- WITH
  - “private methods” of SQL
- WITH RECURSIVE
  - “while” loop of SQL
SQL 2003
- Turing complete
- OVER and PARTITION BY
```
SELECT dep, salary, SUM(salary) OVER (PARTITION BY dep) FROM ...
```
- OVER and GROUP BY
  - actually, do this in the application, thank you very much
SQL 2008
- SELECT TOP is not official – it’s FETCH FIRST ROWS ONLY
SQL 2011
- OFFSET is EVIL
  - http://use-the-index-luke.com/
  - Also, the author was cool and he was giving these stickers:

Presenter: Markus Winand, SQL expert and author
50% SQL problems are caused by poor query/indexing
CREATE INDEX is not in the standard!
The solution- indexing is a development task!
And now the author hits the spots when he explains that in
- 11 SQL books he analyzed only 1% of the pages are about indexes
- 14 database administration books he analyzed only 6% of the pages are about indexes
Everybody knows indexing is important for performance, yet nobody takes the time to learn and apply it properly.