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I am bad at my job. App Academy September 28th 2017 Matt Robenolt Matt

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hello @mattrobenolt

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Principal Software Engineer

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This computer stuff is really hard.

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#include int main() { int i = 0; int things[] = {10, 20}; for (; i < 3; i++) { printf("%d\n", things[i]); } return 0; }

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#include int main() { int i = 0; int things[] = {10, 20}; for (; i < 3; i++) { printf("%d\n", things[i]); } return 0; } $ ./program

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#include int main() { int i = 0; int things[] = {10, 20}; for (; i < 3; i++) { printf("%d\n", things[i]); } return 0; } $ ./program 10 20 619512036

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#include int main() { int i = 0; int things[] = {10, 20}; for (; i < 3; i++) { printf("%d\n", things[i]); } return 0; } $ ./program 10 20 619512036 $ ./program 10 20 369033241

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#include int main() { int i = 0; int things[] = {10, 20}; for (; i < 3; i++) { printf("%d\n", things[i]); } return 0; } Physical Memory Chip 0x0000 0x0004 4 bytes 0x0008 0x000C 0xFFFF

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#include int main() { int i = 0; int things[] = {10, 20}; for (; i < 3; i++) { printf("%d\n", things[i]); } return 0; } Physical Memory Chip 0x0000 0x0004 4 bytes 0x0008 0x000C 0xFFFF 0x0000 (0)

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#include int main() { int i = 0; int things[] = {10, 20}; for (; i < 3; i++) { printf("%d\n", things[i]); } return 0; } Physical Memory Chip 0x0000 0x0004 4 bytes 0x0008 0x000C 0xFFFF 0x000A (10) 0x0014 (20) 0x0000 (0)

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#include int main() { int i = 0; int things[] = {10, 20}; for (; i < 3; i++) { printf("%d\n", things[i]); } return 0; } Physical Memory Chip 0x0000 4 bytes 0x0008 0x000C 0xFFFF 0x000A (10) 0x0014 (20) 0x0000 (0) 0x0004

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#include int main() { int i = 0; int things[] = {10, 20}; for (; i < 3; i++) { printf("%d\n", things[i]); } return 0; } Physical Memory Chip 0x0000 4 bytes 0x0008 0x000C 0xFFFF 0x000A (10) 0x0014 (20) 0x0000 (0) 0x0004 “address of things” + (i * sizeof(int))

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#include int main() { int i = 0; int things[] = {10, 20}; for (; i < 3; i++) { printf("%d\n", things[i]); } return 0; } Physical Memory Chip 0x0000 4 bytes 0x0008 0x000C 0xFFFF 0x000A (10) 0x0014 (20) 0x0000 (0) 0x0004 0x0004 + (0 * 4) == 0x0004 &0x0004 == 0x000A (10)

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#include int main() { int i = 0; int things[] = {10, 20}; for (; i < 3; i++) { printf("%d\n", things[i]); } return 0; } Physical Memory Chip 0x0000 4 bytes 0x0008 0x000C 0xFFFF 0x000A (10) 0x0014 (20) 0x0001 (1) 0x0004

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#include int main() { int i = 0; int things[] = {10, 20}; for (; i < 3; i++) { printf("%d\n", things[i]); } return 0; } Physical Memory Chip 0x0000 4 bytes 0x0008 0x000C 0xFFFF 0x000A (10) 0x0014 (20) 0x0001 (1) 0x0004 0x0004 + (1 * 4) == 0x0008 &0x0008 == 0x0014 (20)

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#include int main() { int i = 0; int things[] = {10, 20}; for (; i < 3; i++) { printf("%d\n", things[i]); } return 0; } Physical Memory Chip 0x0000 4 bytes 0x0008 0x000C 0xFFFF 0x000A (10) 0x0014 (20) 0x0002 (2) 0x0004

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#include int main() { int i = 0; int things[] = {10, 20}; for (; i < 3; i++) { printf("%d\n", things[i]); } return 0; } Physical Memory Chip 0x0000 4 bytes 0x0008 0x000C 0xFFFF 0x000A (10) 0x0014 (20) 0x0002 (2) 0x0004 0x0004 + (2 * 4) == 0x000C &0x000C == ???? ????

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JavaScript is especially hard.

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sentry $ find node_modules -type f | wc -l 36882 sentry $ du -hs node_modules 308M node_modules

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function multiply() { var rv = 1; for (var i = 0; i < arguments.length; i++) rv += arguments[i]; return rv; } > multiply(2, 2) <- 4

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test('multiply 2 * 2 to equal 4', () => { expect(multiply(2, 2)).toBe(4); }); 100% test coverage btw

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> multiply(2, 2) <- 4

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> multiply(2, 2) <- 4 > multiply() <- 1

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> multiply(2, 2) <- 4 > multiply() <- 1 > multiply(1, 1) <- 3

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> multiply(2, 2) <- 4 > multiply() <- 1 > multiply(1, 1) <- 3 > multiply(1, {}) <- "2[object Object]"

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Shipping code is the worst.

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window.Notification.requestPermission().then(function() { new Notification("I see you."); });

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Yas, I did it!

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I think my computer is broken.

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Step 1:

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Step 1: Acceptance

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This is hard. But that’s ok.

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Step 2:

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Step 2: Self-awareness

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You won’t know everything. You will make mistakes. But that’s OK.

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Step 3:

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Step 3: Do your best

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Learn from mistakes. assume the worst.

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How to deal with production.

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Bug-free code is very rare.

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Respond quickly when things are broken.

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Monitoring is good.

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Meet Sentry.

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Error reporting

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window.Notification.requestPermission().then(function() { new Notification("I see you."); });

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Context is good.

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Questions? I may or may not have answers. @mattrobenolt github.com/mattrobenolt sentry.io github.com/getsentry/sentry