Notes on technology, people, and everyday life. Sometimes a technical deep dive; sometimes a thought I wanted to put into words.https://tngeene.com/en-gbhttps://tngeene.com/notes/the-tools-that-survived-three-rewrites/https://tngeene.com/notes/the-tools-that-survived-three-rewrites/Across three full rewrites of the same core product, almost nothing survived except the internal tooling — the scripts, dashboards, and CLIs the team built for…Thu, 15 Aug 2024 00:00:00 GMTToolingDXngeene@inflectionstudio.io (Teddy Kihiu)https://tngeene.com/notes/writing-code-you-can-delete/https://tngeene.com/notes/writing-code-you-can-delete/The highest praise I can give a piece of code isn't that it's elegant. It's that someone could delete it in an afternoon without fear, because its boundaries…Thu, 01 Aug 2024 00:00:00 GMTEngineeringMaintainabilityngeene@inflectionstudio.io (Teddy Kihiu)https://tngeene.com/notes/the-studio-model-vs-the-agency-model/https://tngeene.com/notes/the-studio-model-vs-the-agency-model/An agency sells hours. A studio sells judgment — and the distinction shows up in every incentive downstream of it.Mon, 15 Jul 2024 00:00:00 GMTCultureStudioBusinessngeene@inflectionstudio.io (Teddy Kihiu)https://tngeene.com/notes/why-payments-teams-move-slow-on-purpose/https://tngeene.com/notes/why-payments-teams-move-slow-on-purpose/Outside observers read a slow payments release cycle as dysfunction. Usually it's the opposite — it's the one part of the org that has correctly priced in the…Mon, 01 Jul 2024 00:00:00 GMTFintechRiskngeene@inflectionstudio.io (Teddy Kihiu)https://tngeene.com/notes/reconciliation-is-the-real-product/https://tngeene.com/notes/reconciliation-is-the-real-product/Every fintech pitch deck shows the checkout flow. None of them show the reconciliation job that runs at 2am reconciling what the ledger says happened against…Sat, 15 Jun 2024 00:00:00 GMTFintechPaymentsngeene@inflectionstudio.io (Teddy Kihiu)https://tngeene.com/notes/the-cost-of-a-slow-decision/https://tngeene.com/notes/the-cost-of-a-slow-decision/A wrong decision made quickly is usually cheaper than a right decision made slowly, because most decisions are reversible and most delays are not free —…Sat, 01 Jun 2024 00:00:00 GMTLeadershipDecision-Makingngeene@inflectionstudio.io (Teddy Kihiu)https://tngeene.com/notes/hiring-for-judgment-not-resumes/https://tngeene.com/notes/hiring-for-judgment-not-resumes/The best engineers I've hired didn't have the strongest résumés in the pile. They had the clearest answer to "tell me about a time you were wrong and what you…Wed, 15 May 2024 00:00:00 GMTLeadershipHiringngeene@inflectionstudio.io (Teddy Kihiu)https://tngeene.com/notes/systems-at-scale-the-org-chart/https://tngeene.com/notes/systems-at-scale-the-org-chart/Conway's Law gets quoted as trivia. In practice it's closer to a physical constraint: your system will end up shaped like the communication structure of the…Wed, 01 May 2024 00:00:00 GMTSystem DesignLeadershipArchitecturengeene@inflectionstudio.io (Teddy Kihiu)https://tngeene.com/notes/systems-at-scale-the-data-layer/https://tngeene.com/notes/systems-at-scale-the-data-layer/You can rewrite a service in a weekend. You cannot rewrite the shape of the data it's built on top of without a migration that touches every consumer of that…Mon, 15 Apr 2024 00:00:00 GMTSystem DesignDatabasesArchitecturengeene@inflectionstudio.io (Teddy Kihiu)https://tngeene.com/notes/systems-at-scale-the-boundary-problem/https://tngeene.com/notes/systems-at-scale-the-boundary-problem/Every scaling problem I've been called in to fix has eventually turned out to be a boundary problem. Not enough servers, not the wrong database — a boundary…Mon, 01 Apr 2024 00:00:00 GMTSystem DesignArchitectureScalingngeene@inflectionstudio.io (Teddy Kihiu)https://tngeene.com/notes/distributed-monoliths/https://tngeene.com/notes/distributed-monoliths/Every team that splits a monolith into services expects to get microservices. What they often get instead is a distributed monolith — a system with all the…Fri, 01 Mar 2024 00:00:00 GMTSystem DesignScalingArchitecturengeene@inflectionstudio.io (Teddy Kihiu)https://tngeene.com/notes/invisible-fintech-uis/https://tngeene.com/notes/invisible-fintech-uis/The best interfaces I've shipped in fintech are the ones users never mention. Nobody praises a settlement screen for its typography — they praise it for the…Thu, 01 Feb 2024 00:00:00 GMTProductUXFintechngeene@inflectionstudio.io (Teddy Kihiu)https://tngeene.com/notes/engineering-cofounder-first-90-days/https://tngeene.com/notes/engineering-cofounder-first-90-days/The instinct in the first 90 days is to write code — after all, that's what you were hired, or funded, to do. The better use of that time is almost always…Mon, 01 Jan 2024 00:00:00 GMTLeadershipStartupsngeene@inflectionstudio.io (Teddy Kihiu)