CS Hard Problems Joke

This cluster revolves around repeated quotes and variations of the famous aphorism stating that the only hard problems in computer science are cache invalidation, naming things, and off-by-one errors.

πŸ“‰ Falling 0.5x Other
1,683
Comments
20
Years Active
5
Top Authors
#1789
Topic ID

Activity Over Time

2007
9
2008
23
2009
29
2010
48
2011
49
2012
69
2013
76
2014
73
2015
75
2016
91
2017
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2018
74
2019
105
2020
128
2021
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2022
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2023
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2024
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2025
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2026
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Keywords

CS TwoHardThings EWD PARC DWIM youtube.com martinfowler.com TwoHardThings.html naming things invalidation naming computer science cache hard problems science errors computer hard things

Sample Comments

michael_dorfman β€’ Nov 13, 2010 β€’ View on HN

"There are only two hard problems in Computer Science: cache invalidation, naming things, and off-by-one errors."

wlll β€’ Jan 27, 2012 β€’ View on HN

"There are only three hard problems in Computer Science: cache invalidation, naming things, off-by-one errors and pedantry."

johnnyo β€’ Nov 17, 2025 β€’ View on HN

β€œThere are only two hard things in computer science. Cache invalidation, naming things, and off-by-one errors.”

erichocean β€’ Oct 27, 2012 β€’ View on HN

"There are only two hard problems in computer science: cache invalidation, naming things, and off-by-one errors."

kgraves β€’ Aug 4, 2020 β€’ View on HN

"There are only two hard things in Computer Science: cache invalidation, off by one errors and naming things."

jlgaddis β€’ Mar 5, 2017 β€’ View on HN

"There are only two hard things in Computer Science: cache invalidation, naming things, and off-by-one errors."

bell-cot β€’ Jun 14, 2024 β€’ View on HN

"There are only two hard problems in Computer Science: cache invalidation, naming things, and off-by-one errors."

coderholic β€’ Apr 5, 2017 β€’ View on HN

"There are only two hard problems in CS : 1. Naming things. 2. Cache invalidation. 3. Off-by-one errors"

cygx β€’ Nov 7, 2018 β€’ View on HN

There are only two hard things in Computer Science: cache invalidation, naming things and off-by-one errors.

Y_Y β€’ Mar 4, 2017 β€’ View on HN

"There are only two hard things in Computer Science: cache invalidation and naming things, and off-by-one errors."