Episode 2 — React Frontend Architecture NextJS / 2.9 — Custom Hooks and Reusable Logic

2.9.d — Maintainability: naming, structure, and testing hooks

Learning outcomes

Name hooks so grep and onboarding win.
Choose object vs tuple return APIs deliberately.
Test hooks with renderHook and MSW where appropriate.

Naming

useUserSession not useStuff
Prefer verb+noun for actions: useSignOut, useUploadAvatar

Return shape

Objects scale better as fields grow:

return { data, error, refetch };

Tuples (return [x, setX]) are fine for tiny hooks (useToggle) but document order.

Testing

Use @testing-library/react renderHook (or React test utils per version) to assert state transitions without mounting full pages for every branch.

Appendix — Scenario bank (basic → advanced)

Flashcard: symptom → cause → fix → interview phrase.

CH3-001 — Maintainability #1

Level: Beginner
Symptom: duplicate useEffect blocks across 13 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-002 — Maintainability #2

Level: Beginner+
Symptom: duplicate useEffect blocks across 26 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-003 — Maintainability #3

Level: Intermediate
Symptom: duplicate useEffect blocks across 39 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-004 — Maintainability #4

Level: Intermediate+
Symptom: duplicate useEffect blocks across 52 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-005 — Maintainability #5

Level: Advanced
Symptom: duplicate useEffect blocks across 65 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-006 — Maintainability #6

Level: Advanced+
Symptom: duplicate useEffect blocks across 78 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-007 — Maintainability #7

Level: Beginner
Symptom: duplicate useEffect blocks across 91 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-008 — Maintainability #8

Level: Beginner+
Symptom: duplicate useEffect blocks across 104 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-009 — Maintainability #9

Level: Intermediate
Symptom: duplicate useEffect blocks across 117 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-010 — Maintainability #10

Level: Intermediate+
Symptom: duplicate useEffect blocks across 130 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-011 — Maintainability #11

Level: Advanced
Symptom: duplicate useEffect blocks across 143 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-012 — Maintainability #12

Level: Advanced+
Symptom: duplicate useEffect blocks across 156 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-013 — Maintainability #13

Level: Beginner
Symptom: duplicate useEffect blocks across 169 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-014 — Maintainability #14

Level: Beginner+
Symptom: duplicate useEffect blocks across 182 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-015 — Maintainability #15

Level: Intermediate
Symptom: duplicate useEffect blocks across 195 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-016 — Maintainability #16

Level: Intermediate+
Symptom: duplicate useEffect blocks across 8 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-017 — Maintainability #17

Level: Advanced
Symptom: duplicate useEffect blocks across 21 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-018 — Maintainability #18

Level: Advanced+
Symptom: duplicate useEffect blocks across 34 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-019 — Maintainability #19

Level: Beginner
Symptom: duplicate useEffect blocks across 47 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-020 — Maintainability #20

Level: Beginner+
Symptom: duplicate useEffect blocks across 60 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-021 — Maintainability #21

Level: Intermediate
Symptom: duplicate useEffect blocks across 73 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-022 — Maintainability #22

Level: Intermediate+
Symptom: duplicate useEffect blocks across 86 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-023 — Maintainability #23

Level: Advanced
Symptom: duplicate useEffect blocks across 99 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-024 — Maintainability #24

Level: Advanced+
Symptom: duplicate useEffect blocks across 112 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-025 — Maintainability #25

Level: Beginner
Symptom: duplicate useEffect blocks across 125 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-026 — Maintainability #26

Level: Beginner+
Symptom: duplicate useEffect blocks across 138 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-027 — Maintainability #27

Level: Intermediate
Symptom: duplicate useEffect blocks across 151 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-028 — Maintainability #28

Level: Intermediate+
Symptom: duplicate useEffect blocks across 164 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-029 — Maintainability #29

Level: Advanced
Symptom: duplicate useEffect blocks across 177 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-030 — Maintainability #30

Level: Advanced+
Symptom: duplicate useEffect blocks across 190 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-031 — Maintainability #31

Level: Beginner
Symptom: duplicate useEffect blocks across 3 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-032 — Maintainability #32

Level: Beginner+
Symptom: duplicate useEffect blocks across 16 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-033 — Maintainability #33

Level: Intermediate
Symptom: duplicate useEffect blocks across 29 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-034 — Maintainability #34

Level: Intermediate+
Symptom: duplicate useEffect blocks across 42 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-035 — Maintainability #35

Level: Advanced
Symptom: duplicate useEffect blocks across 55 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-036 — Maintainability #36

Level: Advanced+
Symptom: duplicate useEffect blocks across 68 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-037 — Maintainability #37

Level: Beginner
Symptom: duplicate useEffect blocks across 81 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-038 — Maintainability #38

Level: Beginner+
Symptom: duplicate useEffect blocks across 94 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-039 — Maintainability #39

Level: Intermediate
Symptom: duplicate useEffect blocks across 107 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-040 — Maintainability #40

Level: Intermediate+
Symptom: duplicate useEffect blocks across 120 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-041 — Maintainability #41

Level: Advanced
Symptom: duplicate useEffect blocks across 133 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-042 — Maintainability #42

Level: Advanced+
Symptom: duplicate useEffect blocks across 146 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-043 — Maintainability #43

Level: Beginner
Symptom: duplicate useEffect blocks across 159 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-044 — Maintainability #44

Level: Beginner+
Symptom: duplicate useEffect blocks across 172 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-045 — Maintainability #45

Level: Intermediate
Symptom: duplicate useEffect blocks across 185 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-046 — Maintainability #46

Level: Intermediate+
Symptom: duplicate useEffect blocks across 198 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-047 — Maintainability #47

Level: Advanced
Symptom: duplicate useEffect blocks across 11 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-048 — Maintainability #48

Level: Advanced+
Symptom: duplicate useEffect blocks across 24 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-049 — Maintainability #49

Level: Beginner
Symptom: duplicate useEffect blocks across 37 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-050 — Maintainability #50

Level: Beginner+
Symptom: duplicate useEffect blocks across 50 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-051 — Maintainability #51

Level: Intermediate
Symptom: duplicate useEffect blocks across 63 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-052 — Maintainability #52

Level: Intermediate+
Symptom: duplicate useEffect blocks across 76 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-053 — Maintainability #53

Level: Advanced
Symptom: duplicate useEffect blocks across 89 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-054 — Maintainability #54

Level: Advanced+
Symptom: duplicate useEffect blocks across 102 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-055 — Maintainability #55

Level: Beginner
Symptom: duplicate useEffect blocks across 115 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-056 — Maintainability #56

Level: Beginner+
Symptom: duplicate useEffect blocks across 128 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-057 — Maintainability #57

Level: Intermediate
Symptom: duplicate useEffect blocks across 141 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-058 — Maintainability #58

Level: Intermediate+
Symptom: duplicate useEffect blocks across 154 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-059 — Maintainability #59

Level: Advanced
Symptom: duplicate useEffect blocks across 167 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-060 — Maintainability #60

Level: Advanced+
Symptom: duplicate useEffect blocks across 180 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-061 — Maintainability #61

Level: Beginner
Symptom: duplicate useEffect blocks across 193 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-062 — Maintainability #62

Level: Beginner+
Symptom: duplicate useEffect blocks across 6 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-063 — Maintainability #63

Level: Intermediate
Symptom: duplicate useEffect blocks across 19 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-064 — Maintainability #64

Level: Intermediate+
Symptom: duplicate useEffect blocks across 32 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-065 — Maintainability #65

Level: Advanced
Symptom: duplicate useEffect blocks across 45 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-066 — Maintainability #66

Level: Advanced+
Symptom: duplicate useEffect blocks across 58 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-067 — Maintainability #67

Level: Beginner
Symptom: duplicate useEffect blocks across 71 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-068 — Maintainability #68

Level: Beginner+
Symptom: duplicate useEffect blocks across 84 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-069 — Maintainability #69

Level: Intermediate
Symptom: duplicate useEffect blocks across 97 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-070 — Maintainability #70

Level: Intermediate+
Symptom: duplicate useEffect blocks across 110 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-071 — Maintainability #71

Level: Advanced
Symptom: duplicate useEffect blocks across 123 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-072 — Maintainability #72

Level: Advanced+
Symptom: duplicate useEffect blocks across 136 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-073 — Maintainability #73

Level: Beginner
Symptom: duplicate useEffect blocks across 149 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-074 — Maintainability #74

Level: Beginner+
Symptom: duplicate useEffect blocks across 162 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-075 — Maintainability #75

Level: Intermediate
Symptom: duplicate useEffect blocks across 175 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-076 — Maintainability #76

Level: Intermediate+
Symptom: duplicate useEffect blocks across 188 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-077 — Maintainability #77

Level: Advanced
Symptom: duplicate useEffect blocks across 1 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-078 — Maintainability #78

Level: Advanced+
Symptom: duplicate useEffect blocks across 14 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-079 — Maintainability #79

Level: Beginner
Symptom: duplicate useEffect blocks across 27 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-080 — Maintainability #80

Level: Beginner+
Symptom: duplicate useEffect blocks across 40 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-081 — Maintainability #81

Level: Intermediate
Symptom: duplicate useEffect blocks across 53 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-082 — Maintainability #82

Level: Intermediate+
Symptom: duplicate useEffect blocks across 66 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-083 — Maintainability #83

Level: Advanced
Symptom: duplicate useEffect blocks across 79 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-084 — Maintainability #84

Level: Advanced+
Symptom: duplicate useEffect blocks across 92 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-085 — Maintainability #85

Level: Beginner
Symptom: duplicate useEffect blocks across 105 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-086 — Maintainability #86

Level: Beginner+
Symptom: duplicate useEffect blocks across 118 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-087 — Maintainability #87

Level: Intermediate
Symptom: duplicate useEffect blocks across 131 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-088 — Maintainability #88

Level: Intermediate+
Symptom: duplicate useEffect blocks across 144 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-089 — Maintainability #89

Level: Advanced
Symptom: duplicate useEffect blocks across 157 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-090 — Maintainability #90

Level: Advanced+
Symptom: duplicate useEffect blocks across 170 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-091 — Maintainability #91

Level: Beginner
Symptom: duplicate useEffect blocks across 183 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-092 — Maintainability #92

Level: Beginner+
Symptom: duplicate useEffect blocks across 196 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-093 — Maintainability #93

Level: Intermediate
Symptom: duplicate useEffect blocks across 9 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-094 — Maintainability #94

Level: Intermediate+
Symptom: duplicate useEffect blocks across 22 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-095 — Maintainability #95

Level: Advanced
Symptom: duplicate useEffect blocks across 35 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-096 — Maintainability #96

Level: Advanced+
Symptom: duplicate useEffect blocks across 48 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-097 — Maintainability #97

Level: Beginner
Symptom: duplicate useEffect blocks across 61 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-098 — Maintainability #98

Level: Beginner+
Symptom: duplicate useEffect blocks across 74 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-099 — Maintainability #99

Level: Intermediate
Symptom: duplicate useEffect blocks across 87 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-100 — Maintainability #100

Level: Intermediate+
Symptom: duplicate useEffect blocks across 100 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-101 — Maintainability #101

Level: Advanced
Symptom: duplicate useEffect blocks across 113 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-102 — Maintainability #102

Level: Advanced+
Symptom: duplicate useEffect blocks across 126 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-103 — Maintainability #103

Level: Beginner
Symptom: duplicate useEffect blocks across 139 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-104 — Maintainability #104

Level: Beginner+
Symptom: duplicate useEffect blocks across 152 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-105 — Maintainability #105

Level: Intermediate
Symptom: duplicate useEffect blocks across 165 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-106 — Maintainability #106

Level: Intermediate+
Symptom: duplicate useEffect blocks across 178 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-107 — Maintainability #107

Level: Advanced
Symptom: duplicate useEffect blocks across 191 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-108 — Maintainability #108

Level: Advanced+
Symptom: duplicate useEffect blocks across 4 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-109 — Maintainability #109

Level: Beginner
Symptom: duplicate useEffect blocks across 17 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-110 — Maintainability #110

Level: Beginner+
Symptom: duplicate useEffect blocks across 30 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-111 — Maintainability #111

Level: Intermediate
Symptom: duplicate useEffect blocks across 43 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-112 — Maintainability #112

Level: Intermediate+
Symptom: duplicate useEffect blocks across 56 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-113 — Maintainability #113

Level: Advanced
Symptom: duplicate useEffect blocks across 69 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-114 — Maintainability #114

Level: Advanced+
Symptom: duplicate useEffect blocks across 82 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-115 — Maintainability #115

Level: Beginner
Symptom: duplicate useEffect blocks across 95 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-116 — Maintainability #116

Level: Beginner+
Symptom: duplicate useEffect blocks across 108 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-117 — Maintainability #117

Level: Intermediate
Symptom: duplicate useEffect blocks across 121 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-118 — Maintainability #118

Level: Intermediate+
Symptom: duplicate useEffect blocks across 134 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-119 — Maintainability #119

Level: Advanced
Symptom: duplicate useEffect blocks across 147 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-120 — Maintainability #120

Level: Advanced+
Symptom: duplicate useEffect blocks across 160 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-121 — Maintainability #121

Level: Beginner
Symptom: duplicate useEffect blocks across 173 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-122 — Maintainability #122

Level: Beginner+
Symptom: duplicate useEffect blocks across 186 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-123 — Maintainability #123

Level: Intermediate
Symptom: duplicate useEffect blocks across 199 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-124 — Maintainability #124

Level: Intermediate+
Symptom: duplicate useEffect blocks across 12 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-125 — Maintainability #125

Level: Advanced
Symptom: duplicate useEffect blocks across 25 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-126 — Maintainability #126

Level: Advanced+
Symptom: duplicate useEffect blocks across 38 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-127 — Maintainability #127

Level: Beginner
Symptom: duplicate useEffect blocks across 51 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-128 — Maintainability #128

Level: Beginner+
Symptom: duplicate useEffect blocks across 64 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-129 — Maintainability #129

Level: Intermediate
Symptom: duplicate useEffect blocks across 77 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-130 — Maintainability #130

Level: Intermediate+
Symptom: duplicate useEffect blocks across 90 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-131 — Maintainability #131

Level: Advanced
Symptom: duplicate useEffect blocks across 103 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-132 — Maintainability #132

Level: Advanced+
Symptom: duplicate useEffect blocks across 116 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-133 — Maintainability #133

Level: Beginner
Symptom: duplicate useEffect blocks across 129 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-134 — Maintainability #134

Level: Beginner+
Symptom: duplicate useEffect blocks across 142 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-135 — Maintainability #135

Level: Intermediate
Symptom: duplicate useEffect blocks across 155 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-136 — Maintainability #136

Level: Intermediate+
Symptom: duplicate useEffect blocks across 168 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-137 — Maintainability #137

Level: Advanced
Symptom: duplicate useEffect blocks across 181 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-138 — Maintainability #138

Level: Advanced+
Symptom: duplicate useEffect blocks across 194 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-139 — Maintainability #139

Level: Beginner
Symptom: duplicate useEffect blocks across 7 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-140 — Maintainability #140

Level: Beginner+
Symptom: duplicate useEffect blocks across 20 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-141 — Maintainability #141

Level: Intermediate
Symptom: duplicate useEffect blocks across 33 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-142 — Maintainability #142

Level: Intermediate+
Symptom: duplicate useEffect blocks across 46 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-143 — Maintainability #143

Level: Advanced
Symptom: duplicate useEffect blocks across 59 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-144 — Maintainability #144

Level: Advanced+
Symptom: duplicate useEffect blocks across 72 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-145 — Maintainability #145

Level: Beginner
Symptom: duplicate useEffect blocks across 85 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-146 — Maintainability #146

Level: Beginner+
Symptom: duplicate useEffect blocks across 98 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-147 — Maintainability #147

Level: Intermediate
Symptom: duplicate useEffect blocks across 111 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-148 — Maintainability #148

Level: Intermediate+
Symptom: duplicate useEffect blocks across 124 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-149 — Maintainability #149

Level: Advanced
Symptom: duplicate useEffect blocks across 137 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-150 — Maintainability #150

Level: Advanced+
Symptom: duplicate useEffect blocks across 150 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-151 — Maintainability #151

Level: Beginner
Symptom: duplicate useEffect blocks across 163 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-152 — Maintainability #152

Level: Beginner+
Symptom: duplicate useEffect blocks across 176 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-153 — Maintainability #153

Level: Intermediate
Symptom: duplicate useEffect blocks across 189 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-154 — Maintainability #154

Level: Intermediate+
Symptom: duplicate useEffect blocks across 2 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-155 — Maintainability #155

Level: Advanced
Symptom: duplicate useEffect blocks across 15 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-156 — Maintainability #156

Level: Advanced+
Symptom: duplicate useEffect blocks across 28 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-157 — Maintainability #157

Level: Beginner
Symptom: duplicate useEffect blocks across 41 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-158 — Maintainability #158

Level: Beginner+
Symptom: duplicate useEffect blocks across 54 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-159 — Maintainability #159

Level: Intermediate
Symptom: duplicate useEffect blocks across 67 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-160 — Maintainability #160

Level: Intermediate+
Symptom: duplicate useEffect blocks across 80 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-161 — Maintainability #161

Level: Advanced
Symptom: duplicate useEffect blocks across 93 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-162 — Maintainability #162

Level: Advanced+
Symptom: duplicate useEffect blocks across 106 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Cross-feature imports creating cycles.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-163 — Maintainability #163

Level: Beginner
Symptom: duplicate useEffect blocks across 119 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Inconsistent error handling across hooks.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-164 — Maintainability #164

Level: Beginner+
Symptom: duplicate useEffect blocks across 132 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Barrel exports re-export everything slowing IDE.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-165 — Maintainability #165

Level: Intermediate
Symptom: duplicate useEffect blocks across 145 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Testing only snapshots of giant components instead of hook contracts.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-166 — Maintainability #166

Level: Intermediate+
Symptom: duplicate useEffect blocks across 158 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Dead hooks never deleted after feature removal.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-167 — Maintainability #167

Level: Advanced
Symptom: duplicate useEffect blocks across 171 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: Hook undocumented; return tuple order memorized wrongly.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

CH3-168 — Maintainability #168

Level: Advanced+
Symptom: duplicate useEffect blocks across 184 screens or flaky tests after hook refactor.
Maintainability smell: hook name does not match behavior; grep fails.
Root cause class: hooks/ folder becomes junk drawer without prefixes or domains.
Primary remediation: Prefix useDomainAction; group by feature subfolders when scale demands.
Verify: RTL hook test + one story + bundle diff if heavy.
Interview one-liner: Maintainability is grep + tests + naming: hooks should read like a table of contents for behavior.

<< 2.9 Overview