Configuration Languages
The config that runs modern infrastructure — write and fix real JSON, YAML, JSON Schema, Terraform HCL, and Azure Bicep in browser-graded drills, the traps included.
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JSON Essentials22 cards — step 1 of 7Flashcard decks
7 decks · 149 cards · in study order1JSON EssentialsThe lingua franca of APIs and config: the six data types, strict syntax (double quotes, no comments, no trailing commas), nesting, and the parse/serialize model. Pairs with the /config JSON drills.222YAML EssentialsThe language of Kubernetes, CI, and Compose: indentation-as-structure, block vs flow style, block scalars, anchors/aliases, multi-document files, and the infamous type traps. Pairs with the /config YAML drills.243TOML EssentialsTom's Obvious Minimal Language: key = value pairs, [tables] and dotted keys, the string flavors, real typed values (int/float/bool/datetime), arrays, inline tables, and [[array-of-tables]]. The format behind pyproject.toml and Cargo.toml. Pairs with the /config TOML drills.224JSON SchemaThe contract that validates config: type/properties/required, value constraints, enum/const, combinators (oneOf/anyOf/allOf), conditionals (if/then/else), and reuse with $ref. Pairs with the /config JSON Schema drills.215Terraform HCLHashiCorp Configuration Language: blocks & arguments, the core block types (resource/variable/output/module/provider/locals), types & expressions, references & interpolation, and meta-arguments like count/for_each. Pairs with the /config HCL drills.246Azure BicepAzure's infrastructure-as-code DSL that transpiles to ARM JSON: param/var/resource/output/module, single-quoted strings, colon-newline objects, decorators (@secure/@allowed), interpolation, loops and conditions. Pairs with the /config Bicep drills.227Config Languages ComparedThe big picture across JSON, YAML, JSON Schema, HCL, Bicep (and TOML/INI): what each is for, comments, quoting, data types, and how they relate — so you pick the right one and switch between them fluently.14
Config drills
43 drillsCurated resources
verified July 2026Official specs lead. YAML learning is genuinely thin beyond the dense 1.2.2 spec — there's no canonical YAML tutorial, so js-yaml is included as the closest reputable hands-on tool.
Official specs
Introducing JSON (json.org)free · officialThe canonical JSON syntax reference with railroad diagrams for objects, arrays, strings, and numbers.ECMA-404: The JSON Data Interchange Syntaxfree · official specThe formal standards-body definition of valid JSON text (also ISO/IEC 21778) — the authority behind every parser.YAML 1.2.2 Specificationfree · official specThe current YAML spec covering indentation, anchors, and the type rules behind traps like the Norway problem.JSON Schema Specificationfree · official specLists the Core and Validation drafts (current 2020-12) with meta-schemas and migration notes between versions.Terraform Language Documentation (HCL)free · official docsHashiCorp's authoritative reference for HCL syntax, blocks, arguments, expressions, and resource declarations.Bicep Documentationfree · official docsMicrosoft's official hub for Bicep file structure, data types, functions, and deployment — the declarative ARM alternative.
Docs & interactive learning
JSON Schema — Learnfree · officialGuided path from schema basics to building your first schema, plus a Tour of JSON Schema and glossary.Terraform Tutorials (HashiCorp)free · officialHands-on learning hub with Get Started and Fundamentals tracks for writing and applying real HCL.Fundamentals of Bicep (Microsoft Learn path)free · officialThree-module beginner path teaching Bicep syntax, parameters, conditions, loops, and modules with VS Code.
Validators & tools
Ajv — JSON Schema Validatorfree · open sourceThe de facto JavaScript JSON Schema validator (drafts 04 through 2020-12) — used by ESLint, Webpack, and Fastify.js-yaml — YAML parser & dumperfree · open sourceWidely used JS YAML parser passing the full YAML test suite — great for seeing how YAML actually loads.