A small set of long-form essays. Fewer than one per week, because each is written slowly. Topics range from interview patterns to the craft of explanation to the books that shaped this curriculum.
The essays here are intentionally different from the module pages. Modules are structured curriculum. They cover an entire data structure or pattern from first principles. Essays are arguments. They make a claim, defend it with examples, and sometimes annoy people who hold the opposite position. That's the point.
We publish on no schedule. A new essay appears when one is finished, not when a calendar says it should. Each piece goes through at least three drafts before publication; the goal is the writing density of a careful textbook chapter, not the cadence of a blog. If you want every essay delivered, the RSS feed picks up new pieces within an hour of publication.
Essays draw on the same engineering experience that informs the modules: production performance debugging, technical interviews from both sides of the table, and the specific cases where the textbook answer is wrong. They link freely back into the modules where the underlying technique gets a proper treatment. Read them in either order; the cross-references work both ways.
Three essays are currently live. Two more are in draft. If a topic interests you that isn't covered yet, the contact page is the right channel for requests. Topic suggestions land in the queue; not every one ships, but most do.
How long does it take to learn data structures and algorithms? Six to twelve weeks, if the plan matches your deadline. Here are the three study plans behind AlgoMastery's pathways,…
Why is dynamic programming so hard? Because it is taught as a bag of solved problems when it is really a single skill: defining a state small enough to store and complete enough to…
Read →Essay · CraftWhy is binary search so hard to get right? Because the idea is trivial and the boundaries are not: which interval you maintain, how you compute the midpoint, and when you stop each…
Essay · Data StructuresWhen should you use a heap instead of sorting? When you need only the k smallest or largest, when items arrive over time, or when you repeatedly need the current minimum. Sorting p…
Essay · PerformanceIs recursion slower than iteration? Usually by a small constant, sometimes not at all, and occasionally catastrophically, when the recursion recomputes subproblems or exhausts the …
Essay · PerformanceWhy is my hash map slow? Almost always one of four things: a bad hash function, a load factor allowed to climb, keys that are expensive to hash or compare, or cache misses from a m…
Essay · InterviewsHow many LeetCode problems are enough before an interview? Around 100 to 150, chosen to cover the core patterns, beats 500 picked at random. The number that predicts your interview…
Essay · InterviewsAre brain teasers still asked in coding interviews? Big tech formally dropped them years ago, yet the reasoning they test never left: it just moved inside algorithm questions, esti…
Essay · Complexity AnalysisThe difference between O(log n) and O(n log n) is one question: does your algorithm have to touch every element? Binary search discards half the data and never reads most of it. Me…
Essay · Interview PreparationMost coding interview patterns lists are just problem tags. This is a working catalogue: 15 patterns, the cue that identifies each one, the invariant it protects, what it costs, an…
Essay · Craft of ProgrammingMost developers can write a recursive function that passes tests. Far fewer can trace the call stack, name the invariant each frame maintains, or explain why the base case is suffi…
Essay · PerformanceArrays beat linked lists in most real code, and the reason is the memory hierarchy, not Big-O. Here is the cache-locality argument, an honest benchmark sketch, and the short list o…
Essay · Engineering TasteIn algorithm design and in engineering generally, the most expensive bugs are not the ones we make, they are the abstractions we built before we understood the problem. This essay …
Essay · PedagogyA slow reading list: four books that did the heavy lifting when I was learning. What each does best, what each is bad at, and why their strengths don't overlap as much as a glance …
Essay · Pattern RecognitionInterview problems reuse a small catalogue of shapes. The candidate who memorises two hundred problems is running a losing race against the candidate who can classify a new problem…
Essay · Reasoning"O(n)" is not a measurement. It's a contract: a promise about how running time scales <em>given certain assumptions</em>. When those assumptions fail, the contract is void, and fas…
More essays arrive when they're ready. There is no schedule.