If you look at the source code of a typical application, you will likely find business logic tangled with database calls, HTTP requests firing off in the middle of validation rules, and try/catch blocks sprinkled here and there. The biggest casualty of this coupling is testability…

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Loops are so common in programming that we often don’t give them a second thought, but a buggy loop has potentially infinite destructive power as it mindlessly repeats its task however many times it’s asked…

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Despite all its strengths, SQL can be awkward to integrate with host languages such as JavaScript and Python. There’s often an impedance mismatch between SQL’s declarative nature and the host language’s object-oriented or functional paradigms – SQL queries are typically written as strings within the host language, making it difficult to apply composable programming techniques…

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In a relational database, foreign keys are normally used to associate records stored in different tables, but wouldn’t it be nice to define relationships dynamically without having to add extra columns or tables? And while we’re at it, how about having sparse relationships by associating a record directly with any other record like “post X was last edited by user #123” or “post X was flagged for review by user #456” (who happens to be a moderator)?

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What happens when a function call fails? Can you retry without causing any unintended side effects? If the answer is no, then your function is probably not robust enough…

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Over the years I’ve seen all sorts of SQL mistakes made by developers on my teams, and I’ve made quite a few of them myself. I’d like to share what I’ve learned with you, starting with security first…

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First a little context: At Faradai we had been using PostgreSQL on the ext4 file system for a number of years until it recently became evident that the constantly growing database size (over 5 TB at the time) would start to cause issues in general performance, cloud costs, and the ability to have reliable backups. We reviewed a number of alternative file systems, and chose ZFS mainly for its following three features…

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Vendor lock-in: An unfortunate condition that forces a person or company to continue using a disliked product or service just because they invested in it so much. Vendor lock-in used to affect mostly large companies using mission critical legacy applications, but as more and more companies move to the cloud, cloud providers started to rediscover the joys of vendor lock-in by offering “value-added” services that simplify the lives of software developers who have better things in life than managing servers and databases…

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