https://knowledge-base.somyashrestha.space/ In-depth technical study notes — Java, C++, DSA. en Thu, 06 Aug 2026 08:00:00 GMT https://knowledge-base.somyashrestha.space/systemdesign/architecture-styles-modular-monoliths-microservices-service-boundaries.html https://knowledge-base.somyashrestha.space/systemdesign/architecture-styles-modular-monoliths-microservices-service-boundaries.html System Design and Distributed Systems Thu, 06 Aug 2026 08:00:00 GMT A language-neutral guide to choosing architecture constraints, finding cohesive business boundaries, building a disciplined modular monolith, distributing only when the evidence justifies it, and evolving an order platform without creating a distributed monolith. https://knowledge-base.somyashrestha.space/systemdesign/distributed-transactions-sagas-outbox-reliable-workflows.html https://knowledge-base.somyashrestha.space/systemdesign/distributed-transactions-sagas-outbox-reliable-workflows.html System Design and Distributed Systems Thu, 06 Aug 2026 07:58:27 GMT A language-neutral guide to preserving business invariants across independently failing services, choosing between atomic commit and semantic recovery, building sagas and durable workflows, publishing database changes reliably, and operating the complete design in production. https://knowledge-base.somyashrestha.space/systemdesign/observability-sre-capacity-planning-incident-response.html https://knowledge-base.somyashrestha.space/systemdesign/observability-sre-capacity-planning-incident-response.html System Design and Distributed Systems Thu, 06 Aug 2026 07:57:13 GMT A language-neutral guide to producing trustworthy evidence, defining reliability promises, predicting capacity, detecting fast error-budget burn, and leading distributed-system incidents from first alert through verified recovery and lasting improvement. https://knowledge-base.somyashrestha.space/systemdesign/messaging-event-driven-stream-processing.html https://knowledge-base.somyashrestha.space/systemdesign/messaging-event-driven-stream-processing.html System Design and Distributed Systems Thu, 06 Aug 2026 07:51:18 GMT A language-neutral guide to messages, queues, event logs, delivery guarantees, consumer state, replay, schema evolution, stream-time reasoning, production operations, and interview design. https://knowledge-base.somyashrestha.space/systemdesign/replication-partitioning-sharding-quorum-systems.html https://knowledge-base.somyashrestha.space/systemdesign/replication-partitioning-sharding-quorum-systems.html System Design and Distributed Systems Thu, 06 Aug 2026 07:50:48 GMT A language-neutral guide to copying and distributing data, choosing quorum behavior, moving partitions safely, generating identifiers, and reasoning about correctness during replica, network, and routing failures. https://knowledge-base.somyashrestha.space/systemdesign/coordination-consensus-leases-locks.html https://knowledge-base.somyashrestha.space/systemdesign/coordination-consensus-leases-locks.html System Design and Distributed Systems Sun, 02 Aug 2026 09:04:12 GMT A language-neutral guide to making safe shared decisions under partial failure, understanding Raft, using leaders and leases correctly, fencing stale owners, choosing coordination primitives, and explaining production trade-offs in system-design interviews. https://knowledge-base.somyashrestha.space/systemdesign/resilience-retries-backpressure-overload.html https://knowledge-base.somyashrestha.space/systemdesign/resilience-retries-backpressure-overload.html System Design and Distributed Systems Sun, 02 Aug 2026 08:57:30 GMT A language-neutral guide to containing partial failures, budgeting time and retry load, controlling queues and concurrency, surviving overload, recovering dependencies safely, and explaining every trade-off in production and system-design interviews. https://knowledge-base.somyashrestha.space/systemdesign/distributed-systems-time-ordering-consistency.html https://knowledge-base.somyashrestha.space/systemdesign/distributed-systems-time-ordering-consistency.html System Design and Distributed Systems Sun, 02 Aug 2026 08:47:54 GMT A language-neutral guide to reasoning about partial failure, uncertain time, causal order, consistency contracts, partitions, and the production choices that make distributed behavior understandable, testable, and safe. https://knowledge-base.somyashrestha.space/systemdesign/networking-dns-tcp-tls-http-rpc.html https://knowledge-base.somyashrestha.space/systemdesign/networking-dns-tcp-tls-http-rpc.html System Design and Distributed Systems Fri, 31 Jul 2026 06:33:49 GMT A language-neutral guide to how a secure request moves from a name in a client to a backend response, including protocol internals, failure behavior, API choices, production operations, and interview reasoning. https://knowledge-base.somyashrestha.space/systemdesign/scalability-load-balancing-service-discovery-rate-control.html https://knowledge-base.somyashrestha.space/systemdesign/scalability-load-balancing-service-discovery-rate-control.html System Design and Distributed Systems Fri, 31 Jul 2026 06:32:11 GMT A language-neutral guide to growing a service safely, spreading work across changing instances, finding healthy destinations, and controlling demand before overload becomes a cascading failure. https://knowledge-base.somyashrestha.space/systemdesign/data-storage-data-model-selection.html https://knowledge-base.somyashrestha.space/systemdesign/data-storage-data-model-selection.html System Design and Distributed Systems Fri, 31 Jul 2026 06:30:13 GMT A language-neutral guide to choosing data models and storage engines from access patterns, correctness, scale, retention, recovery, security, operations, and cost instead of choosing from product labels. https://knowledge-base.somyashrestha.space/systemdesign/caching-content-delivery.html https://knowledge-base.somyashrestha.space/systemdesign/caching-content-delivery.html System Design and Distributed Systems Fri, 31 Jul 2026 06:24:00 GMT A language-neutral guide to placing reusable copies of data safely, reasoning about freshness and invalidation, protecting origins from bursts, operating multi-layer caches, and explaining the trade-offs clearly in production and system-design interviews. https://knowledge-base.somyashrestha.space/systemdesign/system-design-fundamentals-capacity-estimation.html https://knowledge-base.somyashrestha.space/systemdesign/system-design-fundamentals-capacity-estimation.html System Design and Distributed Systems Thu, 30 Jul 2026 10:40:10 GMT A language-neutral method for turning an unclear product idea into measurable requirements, capacity estimates, architecture decisions, failure plans, and a design that can be explained, tested, operated, and improved. https://knowledge-base.somyashrestha.space/spring/spring-internals-interview-preparation.html https://knowledge-base.somyashrestha.space/spring/spring-internals-interview-preparation.html Spring Thu, 30 Jul 2026 05:11:52 GMT A practical guide to how Spring creates beans, resolves dependencies, applies post-processors, builds proxies, selects auto-configuration, publishes startup events, diagnoses failures, and turns framework knowledge into strong interview and system-design reasoning. https://knowledge-base.somyashrestha.space/spring/caching-scheduling-async-events.html https://knowledge-base.somyashrestha.space/spring/caching-scheduling-async-events.html Spring Wed, 29 Jul 2026 08:53:07 GMT An in-depth and interview-focused guide to Spring Cache, Redis, cache consistency, scheduled work, asynchronous execution, thread pools, application and transactional events, retries, idempotency, and the point where durable messaging becomes necessary. https://knowledge-base.somyashrestha.space/spring/testing-spring-applications.html https://knowledge-base.somyashrestha.space/spring/testing-spring-applications.html Spring Wed, 29 Jul 2026 08:50:31 GMT A practical and interview-focused guide to test strategy, JUnit, Mockito, Spring test slices, full application tests, web and data testing, PostgreSQL Testcontainers, security, contracts, isolation, performance, and reliable production test suites. https://knowledge-base.somyashrestha.space/spring/observability-production-operations.html https://knowledge-base.somyashrestha.space/spring/observability-production-operations.html Spring Wed, 29 Jul 2026 08:49:19 GMT A practical and interview-focused guide to Actuator, health probes, Micrometer metrics, structured logs, correlation, distributed tracing, secure configuration, graceful shutdown, JVM diagnostics, containers, deployment safety, and evidence-based incident troubleshooting. https://knowledge-base.somyashrestha.space/spring/spring-security.html https://knowledge-base.somyashrestha.space/spring/spring-security.html Spring Wed, 29 Jul 2026 08:44:47 GMT A practical and interview-focused guide to authentication, authorization, the servlet security filter chain, sessions, passwords, JWTs, OAuth 2.0, OpenID Connect, method security, browser protections, testing, and production hardening. https://knowledge-base.somyashrestha.space/spring/spring-jdbc-database-access.html https://knowledge-base.somyashrestha.space/spring/spring-jdbc-database-access.html Spring Tue, 28 Jul 2026 05:10:49 GMT A complete guide to JDBC foundations, DataSource and HikariCP, JdbcTemplate, named parameters, row mapping, batching, generated keys, exception translation, transactions, PostgreSQL, security, testing, performance, production operations, and choosing JDBC instead of an ORM. https://knowledge-base.somyashrestha.space/spring/jpa-hibernate-fundamentals.html 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https://knowledge-base.somyashrestha.space/spring/spring-transaction-management.html Spring Tue, 28 Jul 2026 05:02:21 GMT A practical and interview-focused guide to local database transactions, Spring transaction abstractions, declarative boundaries, propagation, isolation, rollback rules, proxies, savepoints, testing, connection pools, external side effects, and production troubleshooting. https://knowledge-base.somyashrestha.space/spring/spring-mvc-rest-apis.html https://knowledge-base.somyashrestha.space/spring/spring-mvc-rest-apis.html Spring Mon, 27 Jul 2026 12:06:53 GMT A complete guide to the servlet request lifecycle, DispatcherServlet, annotated controllers, request and response binding, DTOs, validation, error contracts, HTTP semantics, pagination, versioning, idempotency, file handling, CORS, and production-quality API design. https://knowledge-base.somyashrestha.space/spring/spring-core-fundamentals.html https://knowledge-base.somyashrestha.space/spring/spring-core-fundamentals.html Spring Mon, 27 Jul 2026 12:06:38 GMT A complete mental model of Spring's IoC container, dependency injection, beans, configuration, scopes, lifecycle, component scanning, dependency selection, extension points, and common interview traps. https://knowledge-base.somyashrestha.space/spring/spring-boot-fundamentals.html https://knowledge-base.somyashrestha.space/spring/spring-boot-fundamentals.html Spring Mon, 27 Jul 2026 12:06:21 GMT A practical and interview-focused guide to Spring Boot project structure, starters, auto-configuration, dependency management, startup, external configuration, profiles, embedded servers, executable archives, DevTools, diagnostics, and production-ready foundations. https://knowledge-base.somyashrestha.space/postgresql/extensions-specialized-features.html https://knowledge-base.somyashrestha.space/postgresql/extensions-specialized-features.html PostgreSQL Mon, 27 Jul 2026 06:47:11 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interview-focused guide to B-tree, Hash, GIN, GiST, SP-GiST and BRIN indexes, composite column order, partial and covering indexes, expression indexes, planner decisions and production-safe index design. https://knowledge-base.somyashrestha.space/postgresql/schema-design-data-modeling.html https://knowledge-base.somyashrestha.space/postgresql/schema-design-data-modeling.html PostgreSQL Thu, 23 Jul 2026 08:12:43 GMT A practical and interview-focused guide to relational modeling, normalization, keys, constraints, PostgreSQL data types, deliberate denormalization, arrays, enums and JSONB design. https://knowledge-base.somyashrestha.space/postgresql/advanced-querying.html https://knowledge-base.somyashrestha.space/postgresql/advanced-querying.html PostgreSQL Tue, 21 Jul 2026 06:28:57 GMT A practical and interview-focused guide to composing complex queries with CTEs, recursion, window functions, DISTINCT ON, LATERAL joins and conditional expressions. 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This is the difference between code that looks current and code that looks like 2012. https://knowledge-base.somyashrestha.space/java/exceptions.html https://knowledge-base.somyashrestha.space/java/exceptions.html Java Thu, 16 Jul 2026 12:24:33 GMT Checked vs unchecked, the hierarchy, try-with-resources, custom exceptions, and the judgment call that actually matters in real code — when to wrap, when to propagate, and when to shut up and let it fly. https://knowledge-base.somyashrestha.space/java/generics.html https://knowledge-base.somyashrestha.space/java/generics.html Java Mon, 13 Jul 2026 16:05:11 GMT Type parameters, bounds, wildcards, PECS and type erasure — everything you need to read and write modern Java confidently, explained from the problem they solve up to the tricks the compiler plays behind your back. https://knowledge-base.somyashrestha.space/java/collections.html https://knowledge-base.somyashrestha.space/java/collections.html Java Mon, 13 Jul 2026 16:05:11 GMT Every list, set, map and queue in Java, explained from the ground up in plain language — then taken all the way down to the internals interviewers actually dig into (especially how HashMap really works).