• Fast Feedback Loops

    One of the reasons that I love TDD, is that it promotes fast feedback. You write a line, execute the tests, and see what the results are. I write outside-in-TDD most of the time. Occasionally, I don’t have a clear idea of what tests to write, or I am doing exploratory coding.

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  • Book Review: Designing Data-Intensive Applications

    Designing Data-Intensive Applications is one of the best technical books I’ve read in a long time. Data storage and retrieval is central to most software projects. There is ever-growing ecosystem of databases, stream processing, messaging queues, and other related systems. The book successfully explains how this technologies are different, how they are similar, and how they fit together.

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  • The REPL: Issue 58 - June 2019

    Per-project Postgres

    In this post, Jamey Sharp elaborates on a neat technique to run different versions of postgres on a per-project basis. I learned that you can run postgres on a Unix socket only, without having a port open, which removes the need to manage those ports for each version of postgres. The technique also has the advantage of keeping the data for the project, inside the project directory structure. It illustrates the power and flexibility of Unix tools.

    How to do distributed locking

    Martin Kleppmann writes about distributed locks in general, and in particular the merits of Redlock, a Redis-based distributed-lock algorithm. Kleppmann breaks down the reasons to use a distributed lock, it’s characteristics, and how Redlock in particular is vulnerable to timing attacks. I found this to be great technical writing. The post came about when Kleppmann was researching his book, Desiging Data-Intensive Applications. I finished that book a few days ago, and hope to write a review soon. I can recommend it enough.

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  • The REPL: Issue 57 - May 2019

    We Can Do Better Than SQL

    Simple SQL statements can read almost like English. With just a bit of complexity (e.g. more than one join) they quickly can become almost impossible to dicern. In this post Elvis Pranskevichus critiques SQL’s shortcomings compellingly. He then introduces EdgeQL, a query language designed to fix SQLs shortcomings. This is the first time I’ve heard of it or EdgeDB.

    Is High Quality Software Worth the Cost?

    With his traditional knack for analysis and synthesis, Martin Fowler describes how the familiar trade-off of quality and cost that is intuitive in the physical world doesn’t quite hold for software. Software projects are constantly evolving, requirements changing. Internal quality determines that speed at which features can be delivered. Disregarding internal quality leads to software projects where it becomes almost impossible to continue making changes. I can’t recommend this article enough.

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  • Chasing a Segmentation fault

    Recently, I chased down a segmentation fault occurring in one of our production servers. A segmentation fault cannot be triggered by code is that written completely in Ruby, barring a bug in Ruby itself. The VM manages the memory, making it impossible to access memory in violation of the OS rules.

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