Long-form writing about Go, distributed systems, databases, performance, and the craft of building software.https://ankuranand.com/en-ushttps://ankuranand.com/blog/2026/08/12/building-a-key-value-database-on-s3-in-go/https://ankuranand.com/blog/2026/08/12/building-a-key-value-database-on-s3-in-go/How an LSM tree gives us the right building blocks, and where object storage changes the design.Wed, 12 Aug 2026 00:00:00 GMTGoDatabasesObject storageLSM treeshttps://ankuranand.com/blog/2025/10/04/killing-o-n-how-timing-wheels-expire-10-million-keys-effortlessly-in-golang/https://ankuranand.com/blog/2025/10/04/killing-o-n-how-timing-wheels-expire-10-million-keys-effortlessly-in-golang/How hierarchical timing wheels expire millions of cache entries efficiently in Go without periodic O(n) scans or a timer per key.Sat, 04 Oct 2025 00:00:00 GMTGoData structuresPerformanceCachinghttps://ankuranand.com/blog/2020/03/19/illustrated-tales-of-go-runtime-scheduler/https://ankuranand.com/blog/2020/03/19/illustrated-tales-of-go-runtime-scheduler/An illustrated tour of Go’s runtime scheduler: operating-system foundations, the G-M-P model, work stealing, preemption, and scheduler traces.Thu, 19 Mar 2020 00:00:00 GMTGoRuntimeConcurrencySchedulinghttps://ankuranand.com/blog/2020/01/07/how-to-mock-in-your-go-golang-tests/https://ankuranand.com/blog/2020/01/07/how-to-mock-in-your-go-golang-tests/How to use small interfaces, structs, and hand-written test doubles to isolate dependencies and write focused unit tests with Go's standard library.Tue, 07 Jan 2020 00:00:00 GMTGoTestingMockinghttps://ankuranand.com/blog/2019/09/29/an-in-depth-introduction-to-99-percentile-for-programmers/https://ankuranand.com/blog/2019/09/29/an-in-depth-introduction-to-99-percentile-for-programmers/Why averages and medians hide tail latency, how the 99th percentile exposes it, and how to calculate and interpret p99 with examples in Go.Sun, 29 Sep 2019 00:00:00 GMTGoPerformanceStatisticsLatencyhttps://ankuranand.com/blog/2019/03/14/communicating-sequential-processes-csp-for-go-developer-in-a-nutshell/https://ankuranand.com/blog/2019/03/14/communicating-sequential-processes-csp-for-go-developer-in-a-nutshell/A concise introduction to CSP through processes, synchronous input and output, guarded commands, and the ideas that shaped Go channels.Thu, 14 Mar 2019 00:00:00 GMTGocsppaperhttps://ankuranand.com/blog/2019/02/20/a-visual-guide-to-golang-memory-allocator-from-ground-up/https://ankuranand.com/blog/2019/02/20/a-visual-guide-to-golang-memory-allocator-from-ground-up/A visual guide to Go's memory allocator, from virtual memory and TCMalloc to mspan, mcache, mcentral, mheap, arenas, and object allocation.Wed, 20 Feb 2019 00:00:00 GMTGomemoryinternalshttps://ankuranand.com/blog/2018/11/29/a-closer-look-at-go-golang-type-system/https://ankuranand.com/blog/2018/11/29/a-closer-look-at-go-golang-type-system/A practical guide to Go's named, unnamed, and underlying types, with examples of assignability, conversion, type identity, and compatibility.Thu, 29 Nov 2018 00:00:00 GMTGoType systemhttps://ankuranand.com/blog/2018/09/29/diving-deep-into-the-golang-channels/https://ankuranand.com/blog/2018/09/29/diving-deep-into-the-golang-channels/A source-level tour of Go channels: hchan, sudog, wait queues, buffered storage, blocking sends and receives, select, and goroutine wake-ups.Sat, 29 Sep 2018 00:00:00 GMTGochannelsinternalshttps://ankuranand.com/blog/2018/09/02/the-terrible-performance-cost-of-cors-api-on-the-single-page-application-spa/https://ankuranand.com/blog/2018/09/02/the-terrible-performance-cost-of-cors-api-on-the-single-page-application-spa/How CORS preflight requests add latency to cross-origin APIs, why URL-specific preflight caching may not help, and what SPA designers should consider.Sun, 02 Sep 2018 00:00:00 GMTJavaScriptspacorsperformancehttps://ankuranand.com/blog/2018/08/28/building-a-simple-single-sign-on-sso-server-and-solution-from-scratch-in-node-js/https://ankuranand.com/blog/2018/08/28/building-a-simple-single-sign-on-sso-server-and-solution-from-scratch-in-node-js/Build a minimal token-based single sign-on flow in Node.js, covering redirects, global and local sessions, consumer validation, and single sign-off.Tue, 28 Aug 2018 00:00:00 GMTJavaScriptNode.jsssohttps://ankuranand.com/blog/2018/06/29/es6s-function-destructuring-assignment-is-not-free-lunch/https://ankuranand.com/blog/2018/06/29/es6s-function-destructuring-assignment-is-not-free-lunch/Compare ordinary parameters with object destructuring in Node.js through V8 bytecode, heap usage, garbage collection, and microbenchmarks.Fri, 29 Jun 2018 00:00:00 GMTJavaScripthttps://ankuranand.com/blog/2018/06/15/implement-your-own-call-apply-and-bind-method-in-javascript/https://ankuranand.com/blog/2018/06/15/implement-your-own-call-apply-and-bind-method-in-javascript/Reimplement JavaScript's call(), apply(), and bind() to understand this binding, variable arguments, return values, constructor behavior, and edge cases.Fri, 15 Jun 2018 00:00:00 GMTJavaScripthttps://ankuranand.com/blog/2018/03/28/the-missing-introduction-of-react-js/https://ankuranand.com/blog/2018/03/28/the-missing-introduction-of-react-js/Build the ideas behind React step by step: reusable components, state, setState, declarative rendering, and efficient DOM updates.Wed, 28 Mar 2018 00:00:00 GMTJavaScriptReacthttps://ankuranand.com/blog/2018/03/23/learning-express-js-by-creating-one-from-scratch-part-1/https://ankuranand.com/blog/2018/03/23/learning-express-js-by-creating-one-from-scratch-part-1/Build a small Express-like framework in Node.js, starting with an HTTP server and GET routes, then adding Router, Route, and Layer abstractions.Fri, 23 Mar 2018 00:00:00 GMTJavaScriptNode.jsExpresshttps://ankuranand.com/blog/2017/12/28/learning-notes-javascript-prototype/https://ankuranand.com/blog/2017/12/28/learning-notes-javascript-prototype/How JavaScript's prototype chain works, how constructor prototype properties differ from object [[Prototype]] links, and how inheritance resolves properties.Thu, 28 Dec 2017 00:00:00 GMTJavaScriptPrototypeSelf notesNode.jshttps://ankuranand.com/blog/2017/08/31/learning-notes-node-js-buffer/https://ankuranand.com/blog/2017/08/31/learning-notes-node-js-buffer/How Node.js stores and transmits binary data with Buffer, including allocation APIs, memory behavior, performance, and the internal 8 KB slab pool.Thu, 31 Aug 2017 00:00:00 GMTJavaScriptBufferNode.js8k-poolSelf noteshttps://ankuranand.com/blog/2017/06/03/understanding-non-deterministic-order-of-execution-of-settimeout-vs-setimmediate-in-node-js-event-loop/https://ankuranand.com/blog/2017/06/03/understanding-non-deterministic-order-of-execution-of-settimeout-vs-setimmediate-in-node-js-event-loop/Why setTimeout(0) and setImmediate() can run in either order, explained through Node.js event-loop phases, libuv, clock updates, and process timing.Sat, 03 Jun 2017 00:00:00 GMTJavaScriptevent-loopNode.jslibuvsetImmediatesetTimeouthttps://ankuranand.com/blog/2016/06/18/the-basic-mathematics-of-sql/https://ankuranand.com/blog/2016/06/18/the-basic-mathematics-of-sql/A short introduction to relations, Cartesian products, schemas, attributes, and how those mathematical ideas are represented as SQL tables.Sat, 18 Jun 2016 00:00:00 GMTSQLMathematicsSelf notesProgramming Paradigmshttps://ankuranand.com/blog/2016/04/24/dont-use-mutable-as-defualt-parameter/https://ankuranand.com/blog/2016/04/24/dont-use-mutable-as-defualt-parameter/Why Python evaluates default arguments once, how mutable defaults retain state between calls, and how the None sentinel pattern avoids the problem.Sun, 24 Apr 2016 00:00:00 GMTPythonFunctionFirst-Class FunctionPython basicshttps://ankuranand.com/blog/2016/04/23/object-mechanism-in-python-part1/https://ankuranand.com/blog/2016/04/23/object-mechanism-in-python-part1/An introduction to CPython's object representation through PyObject, PyVarObject, reference counting, type pointers, and variable-sized objects.Sat, 23 Apr 2016 00:00:00 GMTPythonObjecthttps://ankuranand.com/blog/2016/04/23/private-access-in-java/https://ankuranand.com/blog/2016/04/23/private-access-in-java/Why code inside a Java class can access private fields on another instance of the same class, with examples using mutation and equals().Sat, 23 Apr 2016 00:00:00 GMTJavaOOPEncapsulationhttps://ankuranand.com/blog/2016/04/19/efficient-factorials-algorithms/https://ankuranand.com/blog/2016/04/19/efficient-factorials-algorithms/A comparison of recursive, iterative, paired-multiplication, and prime-decomposition approaches to computing large factorials in Python and Java.Tue, 19 Apr 2016 00:00:00 GMTFactorialEfficiencyPythonJavaAlgorithms