A complete guide to JSON in Kotlin — kotlinx.serialization as the primary choice, Json configuration, SerialName and Transient annotations, nullable and default values, sealed class polymorphism, custom serializers, Gson for Java interop, Moshi, and a library comparison.
A complete guide to YAML in Kotlin — YAML syntax, SnakeYAML for parsing and dumping, reading application configs, kaml with @Serializable, multi-document YAML, YAML vs JSON, validation, and good configuration management patterns.
SQL # MySQL A complete guide to MySQL in Kotlin — connecting with JDBC, HikariCP connection pooling, CRUD with PreparedStatement, transactions, the Exposed ORM with its DSL and DAO APIs, Flyway migrations, and good repository patterns. MSSQL A complete guide to Microsoft SQL Server in Kotlin — JDBC connections with the SQL Server driver, HikariCP, CRUD with PreparedStatement, distinctive T-SQL features, the Exposed ORM with MSSQL, Windows Authentication, stored procedures, and the differences from MySQL.
NoSQL # MongoDB A complete guide to MongoDB in Kotlin — the official MongoDB Driver, MongoClient connections, CRUD with BSON and data classes, filters and projections, aggregation pipelines, indexes, multi-document transactions, KMongo as an idiomatic alternative, and when to choose MongoDB. Elasticsearch A complete guide to Elasticsearch in Kotlin — index and mapping concepts, the Elasticsearch Java Client, document indexing, full-text search, query DSL, aggregations, filters, highlighting, bulk indexing, synchronization patterns with a primary database, and production tips.
Broker # Kafka A complete guide to Apache Kafka in Kotlin — topic and partition concepts, Producers with serialization, Consumers with consumer groups, exactly-once semantics, Kafka with coroutines, error handling and dead letter topics, Kafka Streams, and production tips. RabbitMQ A complete guide to RabbitMQ in Kotlin — Exchange and Queue concepts, Direct, Fanout, Topic, and Headers exchange types, publishing and consuming with the AMQP client, manual acks, dead letter exchanges, the RPC pattern, coroutine integration, and a comparison with Kafka.
Cache # Redis A complete guide to Redis in Kotlin — Lettuce and Jedis as clients, the String, Hash, List, Set, and Sorted Set data types, atomic operations, TTL, caching patterns, session stores, rate limiting, distributed locks, Redis Pub/Sub, pipelines, and connection pools. Memcached A complete guide to Memcached in Kotlin — Memcached vs Redis differences, Spymemcached and XMemcached as clients, basic set/get/delete operations, TTL, CAS (Check-And-Set), multi-get, caching patterns, distributed caching with consistent hashing, and when to choose Memcached.
Frameworks # Quarkus A complete guide to Quarkus in Kotlin — project setup, REST APIs with RESTEasy Reactive, dependency injection with CDI, the Panache ORM, configuration, Bean Validation, testing, GraalVM native images, and a comparison with Spring Boot and Ktor. Ktor A complete guide to Ktor in Kotlin — its plugin architecture, nested routing, JSON serialization, JWT authentication, CORS, rate limiting, validation, the Ktor client for HTTP, WebSockets, testing with testApplication, deployment, and comparisons with other frameworks.
Libraries # Kotlinx.html A complete guide to kotlinx.html in Kotlin — a DSL for generating type-safe HTML, all basic HTML elements, attributes and inline CSS, forms, tables, templates and layouts, Ktor integration, testing HTML output, and when to use kotlinx.html vs a template engine.
A curated collection of resources for learning Kotlin more deeply — official documentation, books, courses, podcasts, YouTube channels, communities, tools and plugins, newsletters, blogs from leading Kotlin developers, and structured learning path guides.