The latest articles on DEV Community by CalcAhead Team (@calcahead). https://dev.to/calcahead https://media2.dev.to/dynamic/image/width=90,height=90,fit=cover,gravity=auto,format=auto/https:%2F%2Fdev-to-uploads.s3.us-east-2.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F4140354%2F345a209c-2483-49fa-819c-b9c5ec72cb27.png https://dev.to/calcahead en CalcAhead Team Mon, 28 Sep 2026 07:25:45 +0000 https://dev.to/calcahead/building-tiem-tra-nho-a-cozy-bubble-tea-shop-game-that-runs-in-the-browser-2k6e https://dev.to/calcahead/building-tiem-tra-nho-a-cozy-bubble-tea-shop-game-that-runs-in-the-browser-2k6e <p>I've been building <strong>Tiem Tra Nho (Little Tea Shop)</strong>, a small management game about running a bubble tea shop. It runs entirely in the browser as plain HTML5 - no install, no account, no engine runtime.</p> <p><strong>Play it here: <a href="https://tiemtranho.com/" rel="noopener noreferrer">https://tiemtranho.com/</a></strong></p> <h2> What the game does </h2> <ul> <li>Take over a small tea shop and decide the menu</li> <li>Buy ingredients, watch your stock, hire staff</li> <li>Serve customers through busy afternoon rushes</li> <li>Progress saves locally in your browser</li> <li>Leaderboards track shop visits and revenue</li> </ul> <h2> Technical notes </h2> <p>The whole thing is a static site, so it loads fast and works on both desktop and mobile browsers. There is no backend account system - saves live in local storage, which keeps the game zero-friction for first-time visitors.</p> <p>The guides are written in English and Vietnamese, since the audience is split between the two.</p> <h2> What I learned </h2> <ul> <li>A tiny scope (one shop, one loop) is much easier to ship than a broad sim</li> <li>Local-only saves remove an enormous amount of signup friction</li> <li>Writing the same guide in two languages forces you to be clear</li> </ul> <p>If you build browser games, I would love to hear how you handle save data and first-run experience.</p> <p><a href="https://tiemtranho.com/" rel="noopener noreferrer">Little Tea Shop</a> - <a href="https://tiemtranho.com/guides" rel="noopener noreferrer">Getting started guide</a></p> gamedev html showdev webdev CalcAhead Team Thu, 24 Sep 2026 04:05:39 +0000 https://dev.to/calcahead/how-i-explain-every-calculator-formula-and-why-worked-examples-matter-4op9 https://dev.to/calcahead/how-i-explain-every-calculator-formula-and-why-worked-examples-matter-4op9 <p>Most online calculators give you a number and stop there. That is fine for a one-off tip calculator, but it falls apart when the decision matters — a loan APR, a weighted GPA, a concrete pour for a patio.</p> <h2> The problem with black-box math </h2> <p>If a page only shows an input and a result, you cannot:</p> <ul> <li>check the rounding rules</li> <li>see which formula version was used</li> <li>catch unit mistakes</li> <li>explain the result to someone else</li> </ul> <h2> What good calculator pages do </h2> <ol> <li> <strong>The working tool</strong> — local computation, no server round-trip</li> <li> <strong>The formula</strong> — written out, not hidden in JS</li> <li> <strong>A worked example</strong> — numbers plugged into that formula</li> <li> <strong>Stated limits</strong> — what the model assumes (and does not)</li> </ol> <h3> Example: monthly loan payment </h3> <p>The standard amortization formula is:</p> <p><code>M = P * r * (1+r)^n / ((1+r)^n - 1)</code></p> <p>where <code>P</code> is principal, <code>r</code> is the monthly rate, and <code>n</code> is the number of months.</p> <p>A worked example with $20,000 at 6% APR over 5 years makes the formula concrete.</p> <h2> Try it </h2> <p>We built <a href="https://calcahead.com?utm_source=dev.to&amp;utm_medium=referral&amp;utm_campaign=backlink_outreach&amp;utm_content=article">CalcAhead</a> around that idea: every page shows the tool, the formula, a worked example, and the limits — money, math, health, dates, grades, and home projects.</p> <p>What calculator frustrates you because it will not show its work?</p>