| # | title | topic | type | difficulty |
|---|---|---|---|---|
| 151 | Mixin pattern: compose behaviors | Patterns & Performance | Coding | Medium |
| 152 | Factory functions vs constructors | Patterns & Performance | Multiple choice | Easy |
| 153 | script: async vs defer | Web Platform | Multiple choice | Medium |
| 154 | What triggers a CORS preflight? | Web Platform | Multiple choice | Hard |
| 155 | no-cache does not mean no cache |
| Web Platform |
| Multiple choice |
| Hard |
| 156 | localStorage, sessionStorage, cookies | Web Platform | Multiple choice | Easy |
| 157 | The call stack: push, run, pop | Event Loop & Memory | Multiple choice | Easy |
| 158 | Two async functions interleave | Event Loop & Memory | Drag & drop | Medium |
| 159 | Microtask starvation | Event Loop & Memory | Multiple choice | Hard |
| 160 | Stack frames and the heap | Event Loop & Memory | Multiple choice | Medium |
| 161 | Find the leak-proof cache | Event Loop & Memory | Multiple choice | Hard |
| 162 | Drag the output: timers scheduling timers | Event Loop & Memory | Drag & drop | Hard |
| 163 | Test the tester: total() | Unit Testing | Write the tests | Easy |
| 164 | Test the tester: maxOf() | Unit Testing | Write the tests | Easy |
| 165 | Test the tester: capitalize() | Unit Testing | Write the tests | Easy |
| 166 | Test the tester: dedupe() | Unit Testing | Write the tests | Medium |
| 167 | Test the tester: clamp() | Unit Testing | Write the tests | Medium |
| 168 | Test the tester: slugify() | Unit Testing | Write the tests | Medium |
| 169 | Test the tester: toCents() | Unit Testing | Write the tests | Hard |
| 170 | Test the tester: range() | Unit Testing | Write the tests | Hard |
| 171 | Test the tester: escapeHtml() | Unit Testing | Write the tests | Hard |
| 172 | Test the tester: LRU cache | Unit Testing | Write the tests | Hard |
| 173 | Test the tester: curry() | Unit Testing | Write the tests | Hard |
| 174 | Test the tester: searchInsert() | Unit Testing | Write the tests | Hard |
| 175 | Test the tester: deepClone() | Unit Testing | Write the tests | Hard |
| 176 | Test the tester: createEmitter() | Unit Testing | Write the tests | Hard |
| 177 | Test the tester: addStrings() | Unit Testing | Write the tests | Hard |
| 178 | Test the tester: memoize() | Unit Testing | Write the tests | Hard |
| 179 | Test the tester: once() | Unit Testing | Write the tests | Medium |
| 180 | Test the tester: reverseString() | Unit Testing | Write the tests | Easy |