guardian/prism
Tool for collecting live data about infrastructure so it can be easily queried by users and automated tooling
GitHub 
4.5K
lines of main code
53 files
1.8K
lines of test code
10 files
1K
lines of other code
16 files
13y
age
4,768 days
15%
main code touched
1 year (711 LOC)
ABCDE
ease of change
for people*
ABCDE
ease of change
for AI*
4.1K
scala
0.2K
ts
0.07K
html
0.04K
xml
0.04K
yaml
MJS
0.01K
mjs
30 days 2026 2025 2024 2023 2022 2021 2020 2019 2018 2017 2016 2015 2014 2013
+0
-0
+89
-53
+236
-120
+864
-380
+4.2K
-1.1K
+412
-161
+1.1K
-465
+6.5K
-5.7K
+432
-261
+489
-185
+896
-222
+1.5K
-558
+79
-199
+2.2K
-881
+2.1K
-626
0

19

31

62

121

55

104

546

58

54

66

119

25

129

83

0

17

20

38

26

41

65

143

16

12

25

37

4

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39

0

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4

4

7

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2

2

2

2026 2025 2024 2023 2022 2021 2020 2019 2018 2017 2016 2015 2014 2013
Rule-of-thumb estimates

Rebuild value

to rebuild
rebuild value

Maintenance effort

per year to maintain
maintenance cost per year
Rules of thumb, not measurements: one man-year rebuilds about 10,000 lines of main code (design, testing and coordination included), and keeping a code base alive takes about 15% of its rebuild value per year (20 man-years of rebuild value need about 3 man-years of maintenance every year). Your changes are remembered in this browser for every report.