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Holly Cummins
Red Hat
Things You Thought
You Didn’t Need To
Care About That Have a
Big Impact On Your Job
Devoxx UK 2025
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@hollycummins.com #RedHat
invisible forces shaping your job
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why is everything hard?
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why are computers terrible?
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geography 101
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geography 101
norway
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@hollycummins.com #RedHat
ski_regions:
- fr
- ch
- no
- se
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@hollycummins.com #RedHat
ski_regions:
- fr
- ch
- no
- se
{"ski_regions": ["fr", "ch", false, "se"]}
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@hollycummins.com #RedHat
ski_regions:
- fr
- ch
- no
- se
{"ski_regions": ["fr", "ch", false, "se"]}
false
- no
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@hollycummins.com #RedHat
well-intentioned decision
had bad outcome
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how can we know what
outcomes our decisions
will have?
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how can we make decisions
in an uncertain world?
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statistics 101
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@hollycummins.com #RedHat
what do you call a
statistician who lives
in san francisco?
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geography 201
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@hollycummins.com #RedHat
what do you call a statistician who lives in san francisco?
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@hollycummins.com #RedHat
what do you call a statistician who lives in san francisco?
a data scientist.
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@hollycummins.com #RedHat
statistics
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@hollycummins.com #RedHat
data science
statistics
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@hollycummins.com #RedHat
data science
statistics
machine learning
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@hollycummins.com #RedHat
data science
statistics
AI
machine learning
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@hollycummins.com #RedHat
even if you’re not doing AI,
statistics is important
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Bayes’
theory
statistics 101
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@hollycummins.com #RedHat
𝖯
(
𝖠
∣
𝖡
) =
𝖯
(
𝖡
∣
𝖠
) ⋅
𝖯
(
𝖠
)
𝖯
(
𝖡
)
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@hollycummins.com #RedHat
𝖯
(
𝖠
∣
𝖡
) =
𝖯
(
𝖡
∣
𝖠
) ⋅
𝖯
(
𝖠
)
𝖯
(
𝖡
)
probability of A, given B
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@hollycummins.com #RedHat
𝖯
(
𝖠
∣
𝖡
) =
𝖯
(
𝖡
∣
𝖠
) ⋅
𝖯
(
𝖠
)
𝖯
(
𝖡
)
probability of A, given B probability of
B, given A
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@hollycummins.com #RedHat
𝖯
(
𝖠
∣
𝖡
) =
𝖯
(
𝖡
∣
𝖠
) ⋅
𝖯
(
𝖠
)
𝖯
(
𝖡
)
probability of A, given B probability of
B, given A probability of A
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@hollycummins.com #RedHat
𝖯
(
𝖠
∣
𝖡
) =
𝖯
(
𝖡
∣
𝖠
) ⋅
𝖯
(
𝖠
)
𝖯
(
𝖡
)
probability of A, given B probability of
B, given A probability of A
probability of B
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@hollycummins.com #RedHat
𝖯
(
𝖠
∣
𝖡
) =
𝖯
(
𝖡
∣
𝖠
) ⋅
𝖯
(
𝖠
)
𝖯
(
𝖡
)
probability of A, given B probability of
B, given A probability of A
probability of B
guidance for a decision
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@hollycummins.com #RedHat
𝖯
(
𝗋𝖺𝗂𝗇
∣
𝖼𝗅𝗈 𝗎𝖽𝗌
)
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@hollycummins.com #RedHat
𝖯
(
𝗋𝖺𝗂𝗇
∣
𝖼𝗅𝗈 𝗎𝖽𝗌
) =
𝖯
(
𝖼
𝗅𝗈𝗎
𝖽 𝗌
∣
𝗋𝖺𝗂𝗇
) ⋅
𝖯
(
𝗋
𝖺 𝗂𝗇
)
𝖯
(
𝖼𝗅 𝗈
𝗎 𝖽
𝗌
)
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@hollycummins.com #RedHat
𝖯
(
𝗋𝖺𝗂𝗇
∣
𝖼𝗅𝗈 𝗎𝖽𝗌
) =
𝖯
(
𝖼
𝗅𝗈𝗎
𝖽 𝗌
∣
𝗋𝖺𝗂𝗇
) ⋅
𝖯
(
𝗋
𝖺 𝗂𝗇
)
𝖯
(
𝖼𝗅 𝗈
𝗎 𝖽
𝗌
)
will I need an umbrella?
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@hollycummins.com #RedHat
𝖯
(
𝗋𝖺𝗂𝗇
∣
𝖼𝗅𝗈 𝗎𝖽𝗌
) =
𝖯
(
𝖼
𝗅𝗈𝗎
𝖽 𝗌
∣
𝗋𝖺𝗂𝗇
) ⋅
𝖯
(
𝗋
𝖺 𝗂𝗇
)
𝖯
(
𝖼𝗅 𝗈
𝗎 𝖽
𝗌
)
will I need an umbrella?
is this a sunshower?
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@hollycummins.com #RedHat
𝖯
(
𝗋𝖺𝗂𝗇
∣
𝖼𝗅𝗈 𝗎𝖽𝗌
) =
𝖯
(
𝖼
𝗅𝗈𝗎
𝖽 𝗌
∣
𝗋𝖺𝗂𝗇
) ⋅
𝖯
(
𝗋
𝖺 𝗂𝗇
)
𝖯
(
𝖼𝗅 𝗈
𝗎 𝖽
𝗌
)
will I need an umbrella?
is this a sunshower?
how often does
it rain in the UK?
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@hollycummins.com #RedHat
𝖯
(
𝗋𝖺𝗂𝗇
∣
𝖼𝗅𝗈 𝗎𝖽𝗌
) =
𝖯
(
𝖼
𝗅𝗈𝗎
𝖽 𝗌
∣
𝗋𝖺𝗂𝗇
) ⋅
𝖯
(
𝗋
𝖺 𝗂𝗇
)
𝖯
(
𝖼𝗅 𝗈
𝗎 𝖽
𝗌
)
will I need an umbrella?
is this a sunshower?
how often does
it rain in the UK?
is it often cloudy in the UK?
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@hollycummins.com #RedHat
𝖯
(
𝗋𝖺𝗂𝗇
∣
𝖼𝗅𝗈 𝗎𝖽𝗌
) =
𝟫𝟫
% ⋅
𝟦
𝟤
%
𝟦𝟥
%
= 97 %
will I need an umbrella? is this not a
sunshower?
how often does
it rain in london?
how often is it cloudy
in london?
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@hollycummins.com #RedHat
𝖯
(
𝗋𝖺𝗂𝗇
∣
𝖼𝗅𝗈 𝗎𝖽𝗌
) =
𝟫𝟫
% ⋅
𝟦
𝟤
%
𝟦𝟥
%
= 97 %
will I need an umbrella? is this not a
sunshower?
how often does
it rain in london?
how often is it cloudy
in london?
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@hollycummins.com #RedHat
𝖯
(
𝗋𝖺𝗂𝗇
∣
𝖼𝗅𝗈 𝗎𝖽𝗌
) =
𝟫𝟫
% ⋅
𝟦
𝟤
%
𝟫𝟢
%
= 46 %
will I need an umbrella? is this not a
sunshower?
how often does
it rain in london?
how often is it cloudy
in london?
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Slide 39 text
@hollycummins.com #RedHat
𝖯
(
𝖠
∣
𝖡
) =
𝖯
(
𝖡
∣
𝖠
) ⋅
𝖯
(
𝖠
)
𝖯
(
𝖡
)
probability of B, given A
guidance for a decision
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Slide 40 text
@hollycummins.com #RedHat
𝖯
(
𝖠
∣
𝖡
) =
𝖯
(
𝖡
∣
𝖠
) ⋅
𝖯
(
𝖠
)
𝖯
(
𝖡
)
probability of B, given A
what if I don’t know any of these numbers??
guidance for a decision
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@hollycummins.com #RedHat
𝖯
(
𝖠
∣
𝖡
) =
𝖯
(
𝖡
∣
𝖠
) ⋅
𝖯
(
𝖠
)
𝖯
(
𝖡
)
probability of B, given A
what if I don’t know any of these numbers??
or this one?
guidance for a decision
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@hollycummins.com #RedHat
𝖯
(
𝖠
∣
𝖡
) =
𝖯
(
𝖡
∣
𝖠
) ⋅
𝖯
(
𝖠
)
𝖯
(
𝖡
)
probability of B, given A
what if I don’t know any of these numbers??
or this one?
guidance for a decision
most useless
formula ever?
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@hollycummins.com #RedHat
𝖯
(
𝖠
∣
𝖡
) =
𝖯
(
𝖡
∣
𝖠
) ⋅
𝖯
(
𝖠
)
𝖯
(
𝖡
)
probability of B, given A
guess! guess!
guess!
guidance for a decision
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@hollycummins.com #RedHat
initial belief + new data
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@hollycummins.com #RedHat
initial belief + new data
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@hollycummins.com #RedHat
initial belief + new data
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@hollycummins.com #RedHat
initial belief + new data
improved belief
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
"ignorance... coined into science."
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@hollycummins.com #RedHat
“founded upon an error, and
must be wholly rejected”
"ignorance... coined into science."
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@hollycummins.com #RedHat
“founded upon an error, and
must be wholly rejected”
"ignorance... coined into science."
“perhaps the only error to which
the mathematical world has so
deeply committed itself”
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@hollycummins.com #RedHat
“founded upon an error, and
must be wholly rejected”
"ignorance... coined into science."
“a staggering falsity”
“perhaps the only error to which
the mathematical world has so
deeply committed itself”
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
left of line: 2
right of line: 3
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@hollycummins.com #RedHat
left of line: 2
right of line: 3
guess: 2/5
across
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@hollycummins.com #RedHat
left of line: 2
right of line: 3
guess: 2/5
across
bayesian guess:
3/7 across
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
left of line: 0
right of line: 3
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@hollycummins.com #RedHat
left of line: 0
right of line: 3
guess: 0/3, so
on left bumper
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@hollycummins.com #RedHat
left of line: 0
right of line: 3
guess: 0/3, so
on left bumper
bayesian guess:
1/4 across
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
left of line: 0
right of line: 0
bayesian guess:
1/2 across
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
left of line: 0
right of line: 1
bayesian guess:
1/3 across
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
left of line: 1
right of line: 1
bayesian guess:
2/4 across
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@hollycummins.com #RedHat
left of line: 1
right of line: 2
bayesian guess:
2/5 across
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
experiment 0: 1 left, 1 right
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@hollycummins.com #RedHat
experiment 0: 1 left, 1 right 1
2
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@hollycummins.com #RedHat
experiment 0: 1 left, 1 right 1
2
experiment 1: 0 left, 1 right
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@hollycummins.com #RedHat
experiment 0: 1 left, 1 right 1
2
1
3
experiment 1: 0 left, 1 right
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@hollycummins.com #RedHat
experiment 0: 1 left, 1 right 1
2
1
3
experiment 1: 0 left, 1 right
experiment 2: 1 left, 0 right
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@hollycummins.com #RedHat
experiment 0: 1 left, 1 right 1
2
1
3
experiment 1: 0 left, 1 right
2
4
experiment 2: 1 left, 0 right
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
experiment 0: 1 left, 1 right 1
2
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@hollycummins.com #RedHat
experiment 0: 1 left, 1 right 1
2
3
7
experiment 1: 2 left, 3 right
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
“spamicity”
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@hollycummins.com #RedHat
artificial intelligence
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@hollycummins.com #RedHat
top tip
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@hollycummins.com #RedHat
tired: “we have no idea”
top tip
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@hollycummins.com #RedHat
tired: “we have no idea”
wired: “we are adopting bayesian thinking”
top tip
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
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why does concurrency
make my head hurt?
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@hollycummins.com #RedHat
𝖯
(
𝖼𝗈 𝗇𝖼
𝗎 𝗋
𝗋𝖾 𝗇𝖼
𝗒
∣
𝗁
𝖾𝖺𝖽𝖺 𝖼𝗁𝖾
) =
𝖯
(
𝗁 𝖾 𝖺
𝖽 𝖺𝖼
𝗁𝖾
∣
𝖼𝗈𝗇
𝖼 𝗎𝗋𝗋
𝖾𝗇
𝖼𝗒
) ⋅
𝖯
(
𝖼𝗈𝗇
𝖼𝗎𝗋𝗋
𝖾𝗇
𝖼𝗒
)
𝖯
(
𝗁
𝖾𝖺𝖽
𝖺 𝖼𝗁𝖾
)
Slide 98
Slide 98 text
@hollycummins.com #RedHat
𝖯
(
𝖼𝗈 𝗇𝖼
𝗎 𝗋
𝗋𝖾 𝗇𝖼
𝗒
∣
𝗁
𝖾𝖺𝖽𝖺 𝖼𝗁𝖾
) =
𝖯
(
𝗁 𝖾 𝖺
𝖽 𝖺𝖼
𝗁𝖾
∣
𝖼𝗈𝗇
𝖼 𝗎𝗋𝗋
𝖾𝗇
𝖼𝗒
) ⋅
𝖯
(
𝖼𝗈𝗇
𝖼𝗎𝗋𝗋
𝖾𝗇
𝖼𝗒
)
𝖯
(
𝗁
𝖾𝖺𝖽
𝖺 𝖼𝗁𝖾
)
can I blame concurrency for
my headache?
Slide 99
Slide 99 text
@hollycummins.com #RedHat
𝖯
(
𝖼𝗈 𝗇𝖼
𝗎 𝗋
𝗋𝖾 𝗇𝖼
𝗒
∣
𝗁
𝖾𝖺𝖽𝖺 𝖼𝗁𝖾
) =
𝖯
(
𝗁 𝖾 𝖺
𝖽 𝖺𝖼
𝗁𝖾
∣
𝖼𝗈𝗇
𝖼 𝗎𝗋𝗋
𝖾𝗇
𝖼𝗒
) ⋅
𝖯
(
𝖼𝗈𝗇
𝖼𝗎𝗋𝗋
𝖾𝗇
𝖼𝗒
)
𝖯
(
𝗁
𝖾𝖺𝖽
𝖺 𝖼𝗁𝖾
)
can I blame concurrency for
my headache?
how many devs can cope
with concurrency?
Slide 100
Slide 100 text
@hollycummins.com #RedHat
𝖯
(
𝖼𝗈 𝗇𝖼
𝗎 𝗋
𝗋𝖾 𝗇𝖼
𝗒
∣
𝗁
𝖾𝖺𝖽𝖺 𝖼𝗁𝖾
) =
𝖯
(
𝗁 𝖾 𝖺
𝖽 𝖺𝖼
𝗁𝖾
∣
𝖼𝗈𝗇
𝖼 𝗎𝗋𝗋
𝖾𝗇
𝖼𝗒
) ⋅
𝖯
(
𝖼𝗈𝗇
𝖼𝗎𝗋𝗋
𝖾𝗇
𝖼𝗒
)
𝖯
(
𝗁
𝖾𝖺𝖽
𝖺 𝖼𝗁𝖾
)
can I blame concurrency for
my headache?
how many devs can cope
with concurrency?
how much
concurrency is there?
Slide 101
Slide 101 text
@hollycummins.com #RedHat
𝖯
(
𝖼𝗈 𝗇𝖼
𝗎 𝗋
𝗋𝖾 𝗇𝖼
𝗒
∣
𝗁
𝖾𝖺𝖽𝖺 𝖼𝗁𝖾
) =
𝖯
(
𝗁 𝖾 𝖺
𝖽 𝖺𝖼
𝗁𝖾
∣
𝖼𝗈𝗇
𝖼 𝗎𝗋𝗋
𝖾𝗇
𝖼𝗒
) ⋅
𝖯
(
𝖼𝗈𝗇
𝖼𝗎𝗋𝗋
𝖾𝗇
𝖼𝗒
)
𝖯
(
𝗁
𝖾𝖺𝖽
𝖺 𝖼𝗁𝖾
)
can I blame concurrency for
my headache?
how many devs can cope
with concurrency?
how often do heads hurt?
how much
concurrency is there?
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@hollycummins.com #RedHat
𝖯
(
𝖼𝗈 𝗇𝖼
𝗎 𝗋
𝗋𝖾 𝗇𝖼
𝗒
∣
𝗁
𝖾𝖺𝖽𝖺 𝖼𝗁𝖾
) =
𝖯
(
𝗁 𝖾 𝖺
𝖽 𝖺𝖼
𝗁𝖾
∣
𝖼𝗈𝗇
𝖼 𝗎𝗋𝗋
𝖾𝗇
𝖼𝗒
) ⋅
𝖯
(
𝖼𝗈𝗇
𝖼𝗎𝗋𝗋
𝖾𝗇
𝖼𝗒
)
𝖯
(
𝗁
𝖾𝖺𝖽
𝖺 𝖼𝗁𝖾
)
can I blame concurrency for
my headache?
how many devs can cope
with concurrency?
how often do heads hurt?
how much
concurrency is there?
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chip design
electrical
engineering 101
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@hollycummins.com #RedHat
cores per cpu
amd + intel
sources: https://www.reddit.com/r/Amd/comments/6cu5ss/highest_amount_of_cores_per_cpu_amd_vs_intel_year/
and https://www.servethehome.com/amd-and-intel-2p-server-core-count-growth-2010-2022/
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@hollycummins.com #RedHat
cores per cpu
amd + intel
sources: https://www.reddit.com/r/Amd/comments/6cu5ss/highest_amount_of_cores_per_cpu_amd_vs_intel_year/
and https://www.servethehome.com/amd-and-intel-2p-server-core-count-growth-2010-2022/
1
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@hollycummins.com #RedHat
cores per cpu
amd + intel
sources: https://www.reddit.com/r/Amd/comments/6cu5ss/highest_amount_of_cores_per_cpu_amd_vs_intel_year/
and https://www.servethehome.com/amd-and-intel-2p-server-core-count-growth-2010-2022/
1 2
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@hollycummins.com #RedHat
cores per cpu
amd + intel
sources: https://www.reddit.com/r/Amd/comments/6cu5ss/highest_amount_of_cores_per_cpu_amd_vs_intel_year/
and https://www.servethehome.com/amd-and-intel-2p-server-core-count-growth-2010-2022/
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@hollycummins.com #RedHat
cores per cpu
amd + intel
sources: https://www.reddit.com/r/Amd/comments/6cu5ss/highest_amount_of_cores_per_cpu_amd_vs_intel_year/
and https://www.servethehome.com/amd-and-intel-2p-server-core-count-growth-2010-2022/
1 2
48
128
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@hollycummins.com #RedHat
sources: https://www.reddit.com/r/Amd/comments/6cu5ss/highest_amount_of_cores_per_cpu_amd_vs_intel_year/
and https://www.servethehome.com/amd-and-intel-2p-server-core-count-growth-2010-2022/
1 2
48
128
𝖯
(
𝖼 𝗈 𝗇𝖼𝗎
𝗋𝗋𝖾𝗇 𝖼
𝗒
)
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
why?
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@hollycummins.com #RedHat
why?
single-processor performance
has plateaued
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
amdahl’s law
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@hollycummins.com #RedHat
we have to get good
at concurrency
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@hollycummins.com #RedHat
but not all of us
have to :)
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@hollycummins.com #RedHat
𝖯
(
𝗁𝖾𝖺𝖽
𝖺𝖼 𝗁 𝖾
∣
𝖼𝗈𝗇
𝖼𝗎 𝗋
𝗋 𝖾𝗇𝖼𝗒
) < .
𝟣𝟢
the quarkus team:
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@hollycummins.com #RedHat
2022
people thought they had
to do reactive programming
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@hollycummins.com #RedHat
2022
people thought they had
to do reactive programming
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@hollycummins.com #RedHat
2025
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@hollycummins.com #RedHat
framework
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@hollycummins.com #RedHat
framework
fast reactive core
… if it’s quarkus :)
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@hollycummins.com #RedHat
framework
fast reactive core
… if it’s quarkus :)
user code
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@hollycummins.com #RedHat
framework
fast reactive core
… if it’s quarkus :)
user code
reactive programming model
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@hollycummins.com #RedHat
framework
fast reactive core
… if it’s quarkus :)
user code
reactive programming model
virtual threads
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@hollycummins.com #RedHat
framework
fast reactive core
… if it’s quarkus :)
user code
reactive programming model
virtual threads
structured concurrency
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@hollycummins.com #RedHat
quarkus programming model
@RunOnVirtualThread
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why did green threads flop,
and loom succeed?
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@hollycummins.com #RedHat
sources: https://www.reddit.com/r/Amd/comments/6cu5ss/highest_amount_of_cores_per_cpu_amd_vs_intel_year/
and https://www.servethehome.com/amd-and-intel-2p-server-core-count-growth-2010-2022/
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48
128
why did green threads flop,
and loom succeed?
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why was AOT a bad idea,
but GraalVM is a good one?
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meteorology 101
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meteorology 101
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cloud
meteorology 101
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is my encrypted data safe?
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
336 combinations
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@hollycummins.com #RedHat
336 combinations
4 days
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@hollycummins.com #RedHat
jxf
ein
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@hollycummins.com #RedHat
W-E-T-T-E-R-F-U-R
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@hollycummins.com #RedHat
336 combinations
brute force
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@hollycummins.com #RedHat
336 combinations
18 combinations
brute force
bayes-ed
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No content
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quantum
computing
physics 101
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
quantum computers would crack
most public-key cryptography
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@hollycummins.com #RedHat
quantum computers would crack
most public-key cryptography
… but big enough ones don’t exist yet
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@hollycummins.com #RedHat
schrodinger’s
cryptography
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@hollycummins.com #RedHat
quantum computers would crack
most public-key cryptography
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@hollycummins.com #RedHat
quantum computers would crack
most public-key cryptography
… but not all
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@hollycummins.com #RedHat
java 24
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@hollycummins.com #RedHat
KeyPairGenerator g = KeyPairGenerator.getInstance("ML-KEM");
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@hollycummins.com #RedHat
KeyPairGenerator g = KeyPairGenerator.getInstance("ML-KEM");
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why is there all this
hype, always?
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venture capital
business
studies 101
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
baby company
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@hollycummins.com #RedHat
baby company
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@hollycummins.com #RedHat
baby company
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@hollycummins.com #RedHat
funding rounds
baby company
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@hollycummins.com #RedHat
funding rounds
baby company
attracted
investment
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@hollycummins.com #RedHat
funding rounds
baby company
attracted
investment
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@hollycummins.com #RedHat
funding rounds
baby company
attracted
investment
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@hollycummins.com #RedHat
funding rounds
baby company
attracted
investment
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@hollycummins.com #RedHat
funding rounds
baby company
attracted
investment
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@hollycummins.com #RedHat
funding rounds
baby company
attracted
investment
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@hollycummins.com #RedHat
funding rounds
baby company
attracted
investment
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@hollycummins.com #RedHat
funding rounds
baby company
attracted
investment
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@hollycummins.com #RedHat
“exit”
funding rounds
baby company
attracted
investment
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@hollycummins.com #RedHat
“exit”
funding rounds
baby company
IPO
attracted
investment
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@hollycummins.com #RedHat
“exit”
funding rounds
baby company
IPO
acquisition
attracted
investment
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@hollycummins.com #RedHat
“exit”
funding rounds
baby company
IPO
acquisition
attracted
investment
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@hollycummins.com #RedHat
what attracts
investment?
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@hollycummins.com #RedHat
what attracts
investment?
stability
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@hollycummins.com #RedHat
what attracts
investment?
stability
profit
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@hollycummins.com #RedHat
what attracts
investment?
stability
profit
revenue
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@hollycummins.com #RedHat
what attracts
investment?
growth
stability
profit
revenue
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@hollycummins.com #RedHat
what attracts
investment?
growth
stability
profit
excitement
revenue
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@hollycummins.com #RedHat
what attracts
investment?
growth
stability
profit
excitement
revenue
likelihood of selling
stake at a profit
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@hollycummins.com #RedHat
“It’s not simply that one piece of technology is
overhyped, it’s that hype is a necessary ingredient of
the current business ecosystem of the tech industry.”
– Meredith Whittaker
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@hollycummins.com #RedHat
“It’s not simply that one piece of technology is
overhyped, it’s that hype is a necessary ingredient of
the current business ecosystem of the tech industry.”
– Meredith Whittaker
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why can’t I find a job?
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why can’t I find a new job?
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@hollycummins.com #RedHat
Source: indeed.com via https://newsletter.pragmaticengineer.com/p/software-engineering-job-openings?publication_id=458709
usa developer vacancies
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@hollycummins.com #RedHat
Source: indeed.com via https://newsletter.pragmaticengineer.com/p/software-engineering-job-openings?publication_id=458709
uk developer vacancies
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interest rates
macroeconomics
101
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@hollycummins.com #RedHat
ZIRP
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@hollycummins.com #RedHat
ZIRP
“zero interest-rate phenomenon”
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@hollycummins.com #RedHat
0%
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@hollycummins.com #RedHat
<1%
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@hollycummins.com #RedHat
Source: Bank of England
UK interest rates
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@hollycummins.com #RedHat
Source: Bank of England
averting
subprime
collapse
UK interest rates
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@hollycummins.com #RedHat
Source: Bank of England
averting
subprime
collapse
covid
UK interest rates
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@hollycummins.com #RedHat
Source: Bank of England
averting
subprime
collapse
covid
0.1% (!)
UK interest rates
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@hollycummins.com #RedHat
Source: Bank of England
averting
subprime
collapse
covid
0.1% (!)
inflation
shortages
war
UK interest rates
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@hollycummins.com #RedHat
Source: Bank of England
UK interest rates
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@hollycummins.com #RedHat
exit
attracted investment
baby company
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@hollycummins.com #RedHat
exit
attracted investment
baby company
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@hollycummins.com #RedHat
exit
attracted investment
baby company
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@hollycummins.com #RedHat
exit
attracted investment
baby company
risk
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@hollycummins.com #RedHat
ZIRP
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@hollycummins.com #RedHat
software company
ZIRP
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@hollycummins.com #RedHat
government bond
software company
ZIRP
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@hollycummins.com #RedHat
government bond
risk
return
software company
ZIRP
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@hollycummins.com #RedHat
government bond
risk
return
software company
high
ZIRP
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@hollycummins.com #RedHat
government bond
risk
return
software company
high
20% - 500%
ZIRP
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@hollycummins.com #RedHat
government bond
low
risk
return
software company
high
20% - 500%
ZIRP
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@hollycummins.com #RedHat
government bond
low
0%
risk
return
software company
high
20% - 500%
ZIRP
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@hollycummins.com #RedHat
government bond
low
0%
risk
return
software company
high
20% - 500%
ZIRP
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@hollycummins.com #RedHat
government bond
low
4%
risk
return
software company
high
20% - 500%
post-ZIRP
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@hollycummins.com #RedHat
government bond
low
4%
risk
return
software company
high
20% - 500%
post-ZIRP
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@hollycummins.com #RedHat
less investment means less hiring
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@hollycummins.com #RedHat
less investment means less hiring
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what about the ai-lephant in the room?
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is AI killing jobs?
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AI is attracting heavy investment
exit
hype generation
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just because AI makes developers more productive,
doesn’t mean it will reduce the number of developers
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jevon’s paradox
economics 101
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@holly_cummins #RedHat
jevon’s paradox
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@holly_cummins #RedHat
jevon’s paradox
“efficiency improvements can
lead to increased consumption”
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@holly_cummins #RedHat
what we imagine
when we widen roads
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@holly_cummins #RedHat
what we get
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@hollycummins.com #RedHat
software is not going away
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@hollycummins.com #RedHat
1800s
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@hollycummins.com #RedHat
“knocker-up”
1800s
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@hollycummins.com #RedHat
“knocker-up”
1800s
human alarm clock
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@hollycummins.com #RedHat
“knocker-up”
1800s - 1940s
human alarm clock
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@hollycummins.com #RedHat
“knocker-up”
1800s
finite demand
- 1940s
human alarm clock
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@hollycummins.com #RedHat
“knocker-up”
1800s
finite demand
only employees need waking up
- 1940s
human alarm clock
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@hollycummins.com #RedHat
“knocker-up”
1800s
finite demand
only employees need waking up
no one needs waking up more than once
- 1940s
human alarm clock
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@hollycummins.com #RedHat
the more software we have,
the more we want
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
software to do stuff
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@hollycummins.com #RedHat
software to do stuff
software to do more stuff
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@hollycummins.com #RedHat
software to do stuff
software to do more stuff
software to tell people about software
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@hollycummins.com #RedHat
software to do stuff
software to do more stuff
software to tell people about software
software to bypass advertisements in the software
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@hollycummins.com #RedHat
software to do stuff
software to do more stuff
software to tell people about software
software to bypass advertisements in the software
software to bypass the bypass software so ads still show
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@hollycummins.com #RedHat
software to do stuff
software to do more stuff
software to tell people about software
software to bypass advertisements in the software
software to bypass the bypass software so ads still show
software to gamify software
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@hollycummins.com #RedHat
software to do stuff
software to do more stuff
software to tell people about software
software to bypass advertisements in the software
software to bypass the bypass software so ads still show
software to gamify software
software to monitor the software
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@hollycummins.com #RedHat
software to do stuff
software to do more stuff
software to tell people about software
software to bypass advertisements in the software
software to bypass the bypass software so ads still show
software to gamify software
software to monitor the software
software to debug the software
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@hollycummins.com #RedHat
software to do stuff
software to do more stuff
software to tell people about software
software to bypass advertisements in the software
software to bypass the bypass software so ads still show
software to gamify software
software to monitor the software
software to debug the software
software to manage the software
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@hollycummins.com #RedHat
software to do stuff
software to do more stuff
software to tell people about software
software to bypass advertisements in the software
software to bypass the bypass software so ads still show
software to gamify software
software to monitor the software
software to debug the software
software to manage the software
software to write the software
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@hollycummins.com #RedHat
software to do stuff
software to do more stuff
software to tell people about software
software to bypass advertisements in the software
software to bypass the bypass software so ads still show
software to gamify software
software to monitor the software
software to debug the software
software to manage the software
software to write the software
software to manage the software that writes the software
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@hollycummins.com #RedHat
software to do stuff
software to do more stuff
software to tell people about software
software to bypass advertisements in the software
software to bypass the bypass software so ads still show
software to gamify software
software to monitor the software
software to debug the software
software to manage the software
software to write the software
software to manage the software that writes the software
software to try and avoid skynet
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@hollycummins.com #RedHat
software to do stuff
software to do more stuff
software to tell people about software
software to bypass advertisements in the software
software to bypass the bypass software so ads still show
software to gamify software
software to monitor the software
software to debug the software
software to manage the software
software to write the software
software to manage the software that writes the software
software to try and avoid skynet
software to work out the meaning of life
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@hollycummins.com #RedHat
software to do stuff
software to do more stuff
software to tell people about software
software to bypass advertisements in the software
software to bypass the bypass software so ads still show
software to gamify software
software to monitor the software
software to debug the software
software to manage the software
software to write the software
software to manage the software that writes the software
software to try and avoid skynet
software to work out the meaning of life
…
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@hollycummins.com #RedHat
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@hollycummins.com #RedHat
Source: indeed.com via https://newsletter.pragmaticengineer.com/p/software-engineering-job-openings?publication_id=458709
usa developer vacancies
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@hollycummins.com #RedHat
Source: indeed.com via https://newsletter.pragmaticengineer.com/p/software-engineering-job-openings?publication_id=458709
usa developer vacancies
chatgpt
released
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@holly_cummins #RedHat
tl;dpa
(too long; didn’t pay attention)
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@holly_cummins #RedHat
tl;dpa
⁃ statistics is (annoyingly) important, especially bayes
(too long; didn’t pay attention)
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@holly_cummins #RedHat
tl;dpa
⁃ statistics is (annoyingly) important, especially bayes
⁃ to achieve more power, computers have to add more cores
(too long; didn’t pay attention)
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@holly_cummins #RedHat
tl;dpa
⁃ statistics is (annoyingly) important, especially bayes
⁃ to achieve more power, computers have to add more cores
⁃ software is not very good at taking advantage of these cores
(too long; didn’t pay attention)
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@holly_cummins #RedHat
tl;dpa
⁃ statistics is (annoyingly) important, especially bayes
⁃ to achieve more power, computers have to add more cores
⁃ software is not very good at taking advantage of these cores
⁃ for data you want to be secret in 10 years, use quantum-safe crypto
(too long; didn’t pay attention)
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@holly_cummins #RedHat
tl;dpa
⁃ statistics is (annoyingly) important, especially bayes
⁃ to achieve more power, computers have to add more cores
⁃ software is not very good at taking advantage of these cores
⁃ for data you want to be secret in 10 years, use quantum-safe crypto
⁃ the rise of interest rates means a tougher job market
(too long; didn’t pay attention)
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@holly_cummins #RedHat
tl;dpa
⁃ statistics is (annoyingly) important, especially bayes
⁃ to achieve more power, computers have to add more cores
⁃ software is not very good at taking advantage of these cores
⁃ for data you want to be secret in 10 years, use quantum-safe crypto
⁃ the rise of interest rates means a tougher job market
⁃ jevon’s paradox means demand for software will go up even if ai
makes producing software cheaper
(too long; didn’t pay attention)
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slides
@hollycummins.com