ecoming familiar with a codebase could be overwhelming, and its effectiveness is often one of the key differences between a senior and a junior developer. Is there a strategic way to do it? To answer this question, we have to touch on psychological topics like the fear of the unknown, the unknowns mapping and the cognitive load theory. With this broader frame in mind, we will convert some "code search techniques" or "git exploring tricks" into bricks of a more systematic approach.

1. Codebase
orienteering
Brainrepo
Mauro Murru
host @ gitbar podcast (www.gitbar.it)
senior software engineer @ nearform
@brainrepo - brainrepo.dev

4. Knowns to be verified
Knowns to be verified
Known unknowns
Known unknowns
Unknown-knowns
Unknown-knowns
Unknowns-unknowns
Unknowns-unknowns

5. Insights guided by
Internal or external consistency
Learn to ask
Knowns to be verified
Knowns to be verified

6. Topics to delve
Rabbit holes
Cognitive load management
Active procrastination
Known unknowns
Known unknowns

7. keep listening to spot
the ephipany
Unknown knowns
Unknown knowns
james joyce
vincent mcdonnell
james joyce
vincent mcdonnell

8. Obscurity occurs when important
information is not obvious.
Docs = red flag
A keen eye for detail
Read ADR, pr and issues
Unknown unknowns
Unknown unknowns

9. When
Why
How
What
Where
Detective John Kali

10. What
Where
main()
package.json
Code isn’t linear!
Like an urban exploration,
dig through the code

11. What
Where
Know your tools

12. Search selection
Match word tool
Prev / next search
(cmd + shift + f)
F4 / shift + F4
VIM ALTERNATIVE: TELESCOPE

13. Is our search only
a disposable asset?
We can save and
share our searches.
Grasp more info
from the context.

14. Is your repo an
island?
Our project can be consistent with
numerous projects inside the
organisation.
Github advanced search
Sourcegraph search

15. How

16. How
Run it as early as possible
Debugger or console.log could be
useful to create our exploration
landmarks

17. How
If you can’t run
Run in your head reducing the noise exposure

18. Who and when

19. To ping someone,
it is essential to
know who they are.
Who & when
Git || Gitlens

20. Who & when
Git blame

21. Who & when
Git Log
--pretty

22. Who & when
Clicking on the
point I can
quickly see
the diff and see
the file evolution
history

23. Why

24. As a matter of
fact, codebase
knowledge is more
than just lines
of code
A multitude of clues
and relevant whys
can be found in
the PRs and Issues threads.
Why

25. Why
Quick access
to issues and
PRs/MRs

26. how to ask for help
Once the doubt has been identified, we must
know how to ask for help from those who possess
the information.

27. HELP! Next.js
navigation is not
working.
Can't use next/navigation 'redirect' method inside the layout
file
I'm using the "next/navigation" redirect function to redirect
the page to the login page if the session is not found. I'm
using that function inside a server component which is inside
the "layout.tsx" file.
The page doesn't redirects and the screen shows an unhandled
runtime error (Error: NEXT_REDIRECT) that makes me think that
the redirect method is not being executed on the server side,
because the error shows in the client. If I use this same method
inside a component on the "page.tsx" file it works perfectly.
pnpm run dev
Go to localhost:3000
The app should detect that the user is not logged and should
redirect automatically to the login page but the error will
show.
Node: 18.12.1 npm: 8.19.2 Yarn: 1.22.19 pnpm: 7.17.0
next: 13.0.6-canary.1 react: 18.2.0 react-dom: 18.2.0
To Reproduce

28. Anatomy of a well-
crafted question
What I want to know?
Who am I talking to?
Where I am
and how I got there?

29. The etiquette/galateo
of asking for help.
Don’t ask to ask
Makes the
interlocutor lose
time by slowing down
communication
Don’t be lazy
Check the grammar,
spelling and font
(use monospaced font
for code)
Don’t expect
only confirmations
You can find a clue
under every word, so
be open to new ideas
Avoid passive-
aggressive behaviors
Wait, don’t use
urgent/help, share the
answers
You are asking for
help not the
solution!

30. the cost of asking help
Expensive, large bandwidth but
super limited to scale.
Implement the documentation.
Faster, easy to find the
knowledge holder, low signal-
noise ratio.
One to One One to many
Stay in the loop
feature, pr, slack, discord,
news...

31. The emotional impact of the answer
'Illustration: 'Nika Akin''
Make sure you don't interpret
the answer as a judgment
RTFM / STFW
Make this silly answer useful
by asking where (which topic)
and why (for which lack)

32. created by the way
information is presented
to the person
is the result of the
constructive method of
handling information
Germane
the cognitive load
associated with the nature
and subject matter
Intrinsic Extraneous

33. 7 ± 2 elements
20 sec. Duration
(Miller 1956)
Continuous evolution
Synaptic Plasticity during sleep
(Sleep function and synaptic
homeostasis Giulio Tononi, Chiara
Cirelli 2005)
Working memory:
Long term memory:
External world
the cognitive load theory
LEARNING
REM
EMB
ERI
NG
FORGETTING
ATTENTION

34. Know ≠ understand
Know: know the notion
Understand: the concept becomes a part of yourself

35. reduce the
cognitive load
The Vilfredo Pareto’s rule: 80/20

36. spot the gems
Look at the first commits
https://github.com/mercurius-js/mercurius/commit/main?
after=4c8242...+300&branch=main
git log --reverse --all | head -30

37. Find the hot spots
Look at the parts that
change frequently
git log --pretty=format: --name-only | sed
'/^s*$/d' | sort | uniq -c | sort -rg |
head -100

38. Manage the leftovers
Activate procrastination with planned revaluation

39. Tdd - Test
driven discovery
E2E: Understand the whole picture
Unit: Limit the scope (blackbox)

40. Tdd - Test
driven discovery
E2E: Understand the whole picture
Unit: Limit the scope (blackbox)

41. A bird eye view
To understand the structure, create a small
chart representing the codebase
or use tools like
Fastify overview (<3 eomm)

43. The senior engineer is not
a strange all-knowing creature.
But whom can
convert fast and effectively
unknown unknowns known unknowns

44. Brainrepo
Mauro Murru
FOLLOW ME ON:
youtube.com/@gitbar
https://www.linkedin.com/in/mauro-murru/
www.brainrepo.dev