Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
The Scientist & The Engineer
Search
Andrew Godwin
February 07, 2020
Programming
1
760
The Scientist & The Engineer
My keynote from PyCon Colombia 2020.
Andrew Godwin
February 07, 2020
Tweet
Share
More Decks by Andrew Godwin
See All by Andrew Godwin
Reconciling Everything
andrewgodwin
1
310
Django Through The Years
andrewgodwin
0
200
Writing Maintainable Software At Scale
andrewgodwin
0
440
A Newcomer's Guide To Airflow's Architecture
andrewgodwin
0
350
Async, Python, and the Future
andrewgodwin
2
660
How To Break Django: With Async
andrewgodwin
1
730
Taking Django's ORM Async
andrewgodwin
0
720
The Long Road To Asynchrony
andrewgodwin
0
660
Pioneering Real-Time
andrewgodwin
0
420
Other Decks in Programming
See All in Programming
「テストは愚直&&網羅的に書くほどよい」という誤解 / Test Smarter, Not Harder
munetoshi
0
190
dbt民主化とLLMによる開発ブースト ~ AI Readyな分析サイクルを目指して ~
yoshyum
3
1.1k
A full stack side project webapp all in Kotlin (KotlinConf 2025)
dankim
0
130
CDK引数設計道場100本ノック
badmintoncryer
1
230
チームのテスト力を総合的に鍛えて品質、スピード、レジリエンスを共立させる/Testing approach that improves quality, speed, and resilience
goyoki
5
980
The Niche of CDK Grant オブジェクトって何者?/the-niche-of-cdk-what-isgrant-object
hassaku63
1
410
Rails Frontend Evolution: It Was a Setup All Along
skryukov
0
230
チームで開発し事業を加速するための"良い"設計の考え方 @ サポーターズCoLab 2025-07-08
agatan
1
450
なぜ「共通化」を考え、失敗を繰り返すのか
rinchoku
1
660
状態遷移図を書こう / Sequence Chart vs State Diagram
orgachem
PRO
2
160
GitHub Copilot and GitHub Codespaces Hands-on
ymd65536
2
150
#QiitaBash MCPのセキュリティ
ryosukedtomita
1
1.4k
Featured
See All Featured
Learning to Love Humans: Emotional Interface Design
aarron
273
40k
Exploring the Power of Turbo Streams & Action Cable | RailsConf2023
kevinliebholz
34
5.9k
Fantastic passwords and where to find them - at NoRuKo
philnash
51
3.3k
The Illustrated Children's Guide to Kubernetes
chrisshort
48
50k
Building Flexible Design Systems
yeseniaperezcruz
328
39k
The Invisible Side of Design
smashingmag
301
51k
Facilitating Awesome Meetings
lara
54
6.5k
Done Done
chrislema
184
16k
RailsConf & Balkan Ruby 2019: The Past, Present, and Future of Rails at GitHub
eileencodes
138
34k
Practical Tips for Bootstrapping Information Extraction Pipelines
honnibal
PRO
20
1.3k
Optimising Largest Contentful Paint
csswizardry
37
3.3k
Design and Strategy: How to Deal with People Who Don’t "Get" Design
morganepeng
130
19k
Transcript
THE SCIENTIST ANDREW GODWIN // @andrewgodwin THE ENGINEER AND
Hi, I’m Andrew Godwin
I call myself an "engineer"
But I studied Computer Science
I knew programming going in. But this was different.
“ Edsger Dijkstra Computer science is no more about computers
than astronomy is about telescopes.
Computer Science is idealistic
"Turing-complete"
We first want to prove it is possible
async def sleep_sort(numbers): async def sleep_add(number): await asyncio.sleep(number) result.append(number) result
= [] await asyncio.wait([ sleep_add(number) for number in numbers ]) return result
We can prove that programs are correct
def is_two(number): return number == 2
>>> import __builtin__ >>> __builtin__.True = False >>> True False
>>> True == False True (Thankfully, only works in Python 2!)
"Communicating Sequential Processes", C. A. R Hoare
contains :: (Ord a) => (Tree a) -> a ->
Bool contains Nil _ = False contains (Node t1 v t2) x | x == v = True | x < v = contains t1 x | x > v = contains t2 x
A perfect world, of perfect programs
“ Benjamin Brewster In theory there is no difference between
theory and practice. In practice there is.
Software Engineering takes shortcuts
When is it safe to take a risk?
None
Software is faster and cheaper to change
The real world is a nasty place
How often does a cosmic ray affect RAM? 36 hours
(for 16GB; "SEU at Ground Level", Eugene Normand) How long can an unpowered SSD keep data? 3 weeks - 1 year (Enterprise at 40ºC, Client at 30ºC; Intel/JEDEC) Does quantum tunneling affect CPUs? Continuously!
Always design for failure
How do we reason about software?
Input Process Output
async def disable_alarm(): ... async def open_door(): ... await asyncio.wait(
[disable_alarm(), open_door()] )
Input Rendering Output Validation Reporting Storage Processing Logging Cache
Django has 250,000 lines of code
An Airbus A380 has 4,000,000 parts
A new car has 100,000,000 lines of code
How are we supposed to handle this?
Abstract, verify and forget
Abstract Define a contract - types, behaviour, exceptions Verify Write
tests to keep the contract valid Forget Work with the contract, not the fine details
You have to learn to forget
Engineering is communication
“ Grace Hopper A ship in port is safe, but
that's not what ships are built for.
Build to expect growth
Build to expect failure
Everyone can build near-perfect software
Know when not to!
Python lets you do both.
Types Start without types, progressively add with mypy Async Make
it work synchronously first. Add async later. Speed Write slow, understandable code. Test it. Then improve it.
Scientists observe and question
Engineers build and invent
All software has consequences
Be the scientist and the engineer
Gracias. Andrew Godwin @andrewgodwin // aeracode.org