[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"me":3,"catalog:en:frontend\u002Ftypescript":4,"config":235},null,{"field_key":5,"field_name":6,"seniority":7,"topic_key":7,"topic_name":7,"spec_key":8,"spec_name":9,"locale":10,"cell_total":11,"field_total":12,"seniorities":13,"topics":17,"specs":136,"samples":150},"frontend","Frontend","","typescript","TypeScript","en",450,2925,[14,15,16],"junior","mid","senior",[18,22,25,28,31,34,37,40,43,46,49,52,55,58,61,64,67,70,73,76,79,82,85,88,91,94,97,100,103,106,109,112,115,118,121,124,127,130,133],{"key":19,"name":20,"count":21},"accessibility","Accessibility",75,{"key":23,"name":24,"count":21},"angular-change-detection","Angular Change Detection",{"key":26,"name":27,"count":21},"angular-components-lifecycle","Angular Components Lifecycle",{"key":29,"name":30,"count":21},"angular-dependency-injection","Angular Dependency Injection",{"key":32,"name":33,"count":21},"angular-directives-pipes","Angular Directives Pipes",{"key":35,"name":36,"count":21},"angular-router-forms","Angular Router Forms",{"key":38,"name":39,"count":21},"angular-testing-performance","Angular Testing Performance",{"key":41,"name":42,"count":21},"css-layout","Css Layout",{"key":44,"name":45,"count":21},"dom-browser-apis","Dom Browser Apis",{"key":47,"name":48,"count":21},"javascript-async-concurrency","Javascript Async Concurrency",{"key":50,"name":51,"count":21},"javascript-language","Javascript Language",{"key":53,"name":54,"count":21},"javascript-memory-performance","Javascript Memory Performance",{"key":56,"name":57,"count":21},"javascript-modules-bundling","Javascript Modules Bundling",{"key":59,"name":60,"count":21},"javascript-prototypes-oop","Javascript Prototypes Oop",{"key":62,"name":63,"count":21},"javascript-runtime-apis","Javascript Runtime Apis",{"key":65,"name":66,"count":21},"javascript-testing-tooling","Javascript Testing Tooling",{"key":68,"name":69,"count":21},"performance","Performance",{"key":71,"name":72,"count":21},"react-components-jsx","React Components Jsx",{"key":74,"name":75,"count":21},"react-context-state","React Context State",{"key":77,"name":78,"count":21},"react-effects-lifecycle","React Effects Lifecycle",{"key":80,"name":81,"count":21},"react-forms-suspense","React Forms Suspense",{"key":83,"name":84,"count":21},"react-hooks-state","React Hooks State",{"key":86,"name":87,"count":21},"react-rendering-performance","React Rendering Performance",{"key":89,"name":90,"count":21},"rendering-reactivity","Rendering Reactivity",{"key":92,"name":93,"count":21},"state-management","State Management",{"key":95,"name":96,"count":21},"testing","Testing",{"key":98,"name":99,"count":21},"typescript-advanced-types","Typescript Advanced Types",{"key":101,"name":102,"count":21},"typescript-generics","Typescript Generics",{"key":104,"name":105,"count":21},"typescript-modules-declarations","Typescript Modules Declarations",{"key":107,"name":108,"count":21},"typescript-narrowing-control-flow","Typescript Narrowing Control Flow",{"key":110,"name":111,"count":21},"typescript-tooling-config","Typescript Tooling Config",{"key":113,"name":114,"count":21},"typescript-type-fundamentals","Typescript Type Fundamentals",{"key":116,"name":117,"count":21},"vue-components-props","Vue Components Props",{"key":119,"name":120,"count":21},"vue-composition-api","Vue Composition Api",{"key":122,"name":123,"count":21},"vue-directives-templates","Vue Directives Templates",{"key":125,"name":126,"count":21},"vue-performance-testing","Vue Performance Testing",{"key":128,"name":129,"count":21},"vue-reactivity-system","Vue Reactivity System",{"key":131,"name":132,"count":21},"vue-router-state-management","Vue Router State Management",{"key":134,"name":135,"count":21},"web-security","Web Security",[137,140,143,146,147],{"key":138,"name":139,"count":11},"angular","Angular",{"key":141,"name":142,"count":11},"javascript","JavaScript",{"key":144,"name":145,"count":11},"react","React",{"key":8,"name":9,"count":11},{"key":148,"name":149,"count":11},"vue","Vue",[151,169,182,196,209,222],{"id":152,"topic":99,"difficulty":153,"body":154,"options":155,"correct_key":160,"explanation":168},"019f7611-bcef-7f28-b0ba-ab2365f0e274",1,"TypeScript ships several built-in utility types that transform an existing type into a new one. Which of these is a built-in utility type?",[156,159,162,165],{"key":157,"text":158},"a","`Optional\u003CT>`",{"key":160,"text":161},"b","`Partial\u003CT>`",{"key":163,"text":164},"c","`Nullable\u003CT>`",{"key":166,"text":167},"d","`Mutable\u003CT>`","`Partial\u003CT>` is one of TypeScript's built-in utility types — it produces a new type where every property of `T` is optional. `Optional`, `Nullable`, and `Mutable` are not part of the standard library (teams sometimes define their own similarly-named helpers, but they aren't built in).",{"id":170,"topic":99,"difficulty":153,"body":171,"options":172,"correct_key":157,"explanation":181},"019f7611-bcf5-7bca-843a-e4227b59f751","```typescript\ninterface User {\n  id: number;\n  name: string;\n  email: string;\n}\ntype UserUpdate = Partial\u003CUser>;\nconst update: UserUpdate = { name: 'Ada' };\n```\nDoes this compile?",[173,175,177,179],{"key":157,"text":174},"Yes — `Partial\u003CUser>` makes every property of `User` optional, so a subset object is valid",{"key":160,"text":176},"No — `update` is missing `id` and `email`, which `User` requires",{"key":163,"text":178},"No — `Partial` can only be applied to classes, not interfaces",{"key":166,"text":180},"Yes, but only because `name` happens to be the first property declared in `User`","`Partial\u003CT>` maps over every property of `T` and marks it optional (`?`). Since `UserUpdate = Partial\u003CUser>`, all of `id`, `name`, and `email` become optional, so an object supplying only `name` satisfies the type. Property declaration order doesn't matter (d).",{"id":183,"topic":99,"difficulty":184,"body":185,"options":186,"correct_key":163,"explanation":195},"019f7611-bcf7-7704-89bc-31d827eba324",2,"```typescript\ninterface Product {\n  id: number;\n  name: string;\n  price: number;\n}\ntype ProductPreview = Pick\u003CProduct, 'id' | 'name'>;\n```\nWhat properties does `ProductPreview` have?",[187,189,191,193],{"key":157,"text":188},"All of `Product`'s properties, with `price` made optional",{"key":160,"text":190},"Only `price`, since `Pick` selects everything NOT listed",{"key":163,"text":192},"Only `id` and `name`, exactly as listed in the second type argument",{"key":166,"text":194},"`id`, `name`, and `price`, since `Pick` keeps the original shape unchanged","`Pick\u003CT, K>` builds a new type containing only the properties named in the union `K`. Here `K` is `'id' | 'name'`, so `ProductPreview` has exactly those two properties — `price` is excluded entirely, not made optional.",{"id":197,"topic":99,"difficulty":184,"body":198,"options":199,"correct_key":166,"explanation":208},"019f7611-bcf8-7415-8106-ee0ce35cab53","```typescript\ninterface Product {\n  id: number;\n  name: string;\n  price: number;\n  internalCode: string;\n}\ntype PublicProduct = Omit\u003CProduct, 'internalCode'>;\n```\nWhat properties does `PublicProduct` have?",[200,202,204,206],{"key":157,"text":201},"Only `internalCode`",{"key":160,"text":203},"All of `Product`'s properties unchanged, including `internalCode`",{"key":163,"text":205},"None — `Omit` with a single string removes all properties",{"key":166,"text":207},"`id`, `name`, and `price` — every property of `Product` except `internalCode`","`Omit\u003CT, K>` is the inverse of `Pick`: it keeps every property of `T` EXCEPT those named in `K`. Here `K` is just `'internalCode'`, so `PublicProduct` retains `id`, `name`, and `price` and drops `internalCode`.",{"id":210,"topic":99,"difficulty":184,"body":211,"options":212,"correct_key":160,"explanation":221},"019f7611-bcf9-717b-ad10-adbfc87a0737","```typescript\ntype Scores = Record\u003C'math' | 'science' | 'art', number>;\nconst s: Scores = { math: 90, science: 85, art: 70 };\n```\nWhat does `Record\u003C'math' | 'science' | 'art', number>` describe?",[213,215,217,219],{"key":157,"text":214},"An array of numbers with exactly 3 elements",{"key":160,"text":216},"An object type with exactly the keys `'math'`, `'science'`, `'art'`, each mapped to a `number`",{"key":163,"text":218},"A union type meaning 'either a string literal or a number'",{"key":166,"text":220},"An object type where any string key is allowed, as long as the value is a `number`","`Record\u003CK, V>` builds an object type whose keys are exactly the members of union `K`, each with value type `V`. So `Record\u003C'math' | 'science' | 'art', number>` requires an object with precisely those three keys, each holding a `number` — omitting one of them, or adding an unlisted key, is a type error.",{"id":223,"topic":99,"difficulty":184,"body":224,"options":225,"correct_key":163,"explanation":234},"019f7611-bcfa-7040-a71c-a69d27818f52","```typescript\nfunction createUser(name: string, age: number) {\n  return { name, age, createdAt: new Date() };\n}\ntype NewUser = ReturnType\u003Ctypeof createUser>;\n```\nWhat does `ReturnType\u003Ctypeof createUser>` produce?",[226,228,230,232],{"key":157,"text":227},"`typeof createUser`, i.e. the literal string `'function'`",{"key":160,"text":229},"`void`, since `ReturnType` only works on functions with no return value",{"key":163,"text":231},"The type of whatever `createUser` returns: `{ name: string; age: number; createdAt: Date }`",{"key":166,"text":233},"A function type identical to `createUser`'s own signature","`typeof createUser` gets the function's TYPE (its call signature), and `ReturnType\u003CF>` extracts the type of what a function type `F` returns. So `NewUser` becomes the inferred return object shape `{ name: string; age: number; createdAt: Date }` — it does not preserve the function signature itself (d), and it isn't a literal string (a).",{"fields":236,"seniorities":410,"interview_shapes":411,"locales":416,"oauth":418,"question_count":421,"coach_enabled":422,"jd_match_enabled":422},[237,262,270,287,311,324,343,362,384,391,397,404],{"key":238,"name_tr":239,"name_en":239,"sort":153,"specializations":240},"backend","Backend",[241,244,247,250,253,256,259],{"key":242,"name":243,"field":238},"general","Genel",{"key":245,"name":246,"field":238},"go","Go",{"key":248,"name":249,"field":238},"python","Python",{"key":251,"name":252,"field":238},"java","Java",{"key":254,"name":255,"field":238},"csharp","C#\u002F.NET",{"key":257,"name":258,"field":238},"nodejs","Node.js",{"key":260,"name":261,"field":238},"php","PHP",{"key":5,"name_tr":6,"name_en":6,"sort":184,"specializations":263},[264,265,266,267,268,269],{"key":242,"name":243,"field":5},{"key":141,"name":142,"field":5},{"key":8,"name":9,"field":5},{"key":144,"name":145,"field":5},{"key":148,"name":149,"field":5},{"key":138,"name":139,"field":5},{"key":271,"name_tr":272,"name_en":272,"sort":273,"specializations":274},"fullstack","Fullstack",3,[275,276,277,278,279,280,281,282,283,284,285,286],{"key":242,"name":243,"field":271},{"key":245,"name":246,"field":238},{"key":248,"name":249,"field":238},{"key":251,"name":252,"field":238},{"key":254,"name":255,"field":238},{"key":257,"name":258,"field":238},{"key":260,"name":261,"field":238},{"key":141,"name":142,"field":5},{"key":8,"name":9,"field":5},{"key":144,"name":145,"field":5},{"key":148,"name":149,"field":5},{"key":138,"name":139,"field":5},{"key":288,"name_tr":289,"name_en":289,"sort":290,"specializations":291},"devops-cloud","DevOps \u002F Cloud",4,[292,293,296,299,302,305,308],{"key":242,"name":243,"field":288},{"key":294,"name":295,"field":288},"aws","AWS",{"key":297,"name":298,"field":288},"gcp","GCP",{"key":300,"name":301,"field":288},"azure","Azure",{"key":303,"name":304,"field":288},"kubernetes","Kubernetes",{"key":306,"name":307,"field":288},"terraform","Terraform",{"key":309,"name":310,"field":288},"linux","Linux",{"key":312,"name_tr":313,"name_en":313,"sort":314,"specializations":315},"ai-engineer","AI Engineer",5,[316,317,318,321],{"key":242,"name":243,"field":312},{"key":248,"name":249,"field":312},{"key":319,"name":320,"field":312},"llm-rag","LLM\u002FRAG",{"key":322,"name":323,"field":312},"mlops","MLOps",{"key":325,"name_tr":326,"name_en":327,"sort":328,"specializations":329},"database","Veritabanı","Database",6,[330,331,334,337,340],{"key":242,"name":243,"field":325},{"key":332,"name":333,"field":325},"postgresql","PostgreSQL",{"key":335,"name":336,"field":325},"mysql","MySQL",{"key":338,"name":339,"field":325},"mongodb","MongoDB",{"key":341,"name":342,"field":325},"redis","Redis",{"key":344,"name_tr":345,"name_en":346,"sort":347,"specializations":348},"mobile","Mobil","Mobile",7,[349,350,353,356,359],{"key":242,"name":243,"field":344},{"key":351,"name":352,"field":344},"ios-swift","iOS (Swift)",{"key":354,"name":355,"field":344},"android-kotlin","Android (Kotlin)",{"key":357,"name":358,"field":344},"flutter","Flutter",{"key":360,"name":361,"field":344},"react-native","React Native",{"key":363,"name_tr":364,"name_en":365,"sort":366,"specializations":367},"security","Güvenlik","Security",8,[368,369,372,375,378,381],{"key":242,"name":243,"field":363},{"key":370,"name":371,"field":363},"appsec","AppSec",{"key":373,"name":374,"field":363},"offensive-pentest","Offensive \u002F Pentest",{"key":376,"name":377,"field":363},"cloud-security","Cloud Security",{"key":379,"name":380,"field":363},"devsecops","DevSecOps",{"key":382,"name":383,"field":363},"blue-team-incident","Blue Team \u002F Incident",{"key":385,"name_tr":386,"name_en":387,"sort":388,"specializations":389},"qa-test-automation","QA \u002F Test Otomasyonu","QA \u002F Test Automation",9,[390],{"key":242,"name":243,"field":385},{"key":392,"name_tr":393,"name_en":393,"sort":394,"specializations":395},"data-engineer","Data Engineer",10,[396],{"key":242,"name":243,"field":392},{"key":398,"name_tr":399,"name_en":400,"sort":401,"specializations":402},"game-dev","Oyun Geliştirme","Game Development",11,[403],{"key":242,"name":243,"field":398},{"key":405,"name_tr":406,"name_en":406,"sort":407,"specializations":408},"ml-engineer","ML Engineer",12,[409],{"key":242,"name":243,"field":405},[14,15,16],{"junior":412,"mid":414,"senior":415},{"questions":413,"median_sec":3},20,{"questions":413,"median_sec":3},{"questions":413,"median_sec":3},[417,10],"tr",[419,420],"google","github",21750,true]