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The multi-part series and running themes, rather than one long pile.

• Series Cats Core

  Learning Typelevel Cats Core in Scala 2 through runnable examples: combining optional values, collecting validation errors, and understanding the type classes behind practical operations.

  9 posts · 50 min · updated 23 Oct 2026

• Series Scala and the JVM

  Learning Scala 2 and Play from a Java and Spring background, step by step: language fundamentals, sbt workflows, domain modelling, asynchronous services, with runnable examples and practical comparisons.

  20 posts · 109 min · updated 19 Oct 2026

• Series LLMs, the whole thing

  Working through large language models from the ground up — turning text into tokens, embeddings and the geometry of meaning, the transformer architecture, attention, how these models are trained, and what separates one generation from the next.

  11 posts · 90 min · updated 20 Sep 2026

• Series Building agents on the JVM with Embabel

  Learning Embabel by building with it, in order — planning, durable sessions, testing without a model, tools, human-in-the-loop, tracing, exposing it over MCP.

  10 posts · 62 min · updated 31 Jul 2026

• Series Shipping an AI feature into my own product

  Build it, attack it, keep extending it — the Ask Zakaria concierge from the first prompt through prompt-injection red-teaming to reading a job description and taking questions by voice.

  4 posts · 29 min · updated 1 Aug 2026

• Topic Traces, Tempo and the LGTM stack

  Instrument it, learn to query it, then point it at something that thinks.

  6 posts · 44 min · updated 17 Oct 2026

• Topic Working with Claude Code

  An agent as a collaborator rather than an autocomplete — design systems, durable knowledge, automation ladders, subagent fleets on my own source, and now in CI.

  28 posts · 199 min · updated 1 Nov 2026

• Topic Working with Codex / ChatGPT

  Using Codex and ChatGPT as engineering collaborators — repository workflows, security reviews, automation, and the practical boundaries that keep the work controlled.

  7 posts · 36 min · updated 8 Oct 2026

• Topic Security and privacy, in practice

  Attacking my own features and reading the protocols underneath them — secrets delivery, response headers, a published address for bad news, a cookie banner that sets no cookies, and what an auth flow is actually protecting you from.

  19 posts · 124 min · updated 1 Nov 2026

• Topic Building this site in public

  Shipping and operating my own product in public — one jar serving two hosts, making it findable, dropping experiments into it, shipping a free CV builder off the side.

  9 posts · 46 min · updated 14 Sep 2026

• Topic Patterns for engineers

  The design and architecture patterns every backend engineer should have at hand — each built as a small, runnable showcase you can watch work, with the trade-offs and the framework gotchas spelled out rather than hand-waved.

  2 posts · 16 min · updated 12 Oct 2026

• Series Learning enumeratum

  A hands-on, lesson-by-lesson walk through enumeratum, the Scala library that turns sealed traits into real enums: autogenerated values, safe parsing from strings, and integrations with JSON and databases. Each post starts from runnable sbt code on Scala 2.13 and compares it with what plain Scala gives you, scala.Enumeration and hand-rolled case objects, so you see why teams reach for it.

  3 posts · 14 min · updated 16 Oct 2026

• Series Guice and play and escaping DI hell

  4 posts · 21 min · updated 25 Oct 2026

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