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I Built a Free Apache Kafka Course from Scratch — Here's the Full Curriculum (and What I Got Wrong) I spent months building a free Apache Kafka course covering everything from first principles to a real-time analytics platform final project. No paywall. No "premium tier." 9 modules, 470 minutes of content, completely free. Here's the full syllabus, the Python code that actually works, and the honest mistakes I made building the curriculum — so you don't repeat them. Why I Built This Every time someone asked me "how do I learn Kafka?", I sent them to the same 3 places: The official Confluent docs (dense, assumes you already know what you're doing) A $15 Udemy course that spends Module 1 explaining what a computer is A YouTube playlist where half the videos are deleted None of them answered the real question beginners have: why does Kafka exist, and what problem does it actually solve before I write a single line of code? That's the gap I built for. The Problem With Most Kafka Tutorials Most tutorials start with: "Kafka is a distributed event streaming platform..." And then they immediately show you a Docker Compose file with 6 services. Beginners copy-paste it, something breaks, they don't know why, they quit. The real problem is that Kafka is an answer to a specific architectural problem — and if you don't understand the problem first, the solution makes no sense. So Module 1 and 2 of this course don't touch Kafka at all. They build the problem statement from scratch. The Full Syllabus (9 Modules, 470 Minutes) Module 1: Introduction to Kafka — 35 min Not "what is Kafka" — but why event streaming exists at all. What breaks in traditional request-response architectures at scale. Module 2: The Problem Statement — 30 min A real-world scenario: you're building an e-commerce platform. Orders, inventory, notifications, analytics — all tightly coupled. What happens when one service goes down? This module makes the pain visceral before Kafka enters the picture. Module 3: How

Building an HSK Speaking Test AI: Real-time Tone Grading with Gemini I built a free Mandarin speaking assessment tool that grades tone + grammar in real time. Here's the engineering behind it. The Problem HSK (Chinese proficiency test) has a speaking component (HSKK), but most learners can't self-assess their level. Online tutors are expensive. Generic AI conversation tools don't grade tones. So I built ToneTutor: a 3-minute spoken-HSK test that estimates your speaking level and identifies weak points. The Tech Stack Frontend: Web Audio API (record user voice → PCM → LINEAR16) React + TypeScript (real-time transcript display) Backend: FastAPI (Python) on Google Cloud Run Gemini 2.5 Flash (real-time conversation + transcript grading) Firestore (user sessions + results) The Challenge: Web Audio API records as WebM. Gemini expects LINEAR16 (WAV). iOS Safari doesn't support WebM. So: Transcode WebM → PCM in browser (Web Audio context) Send raw PCM bytes to backend Backend wraps PCM in WAV header → sends to Gemini Speech-to-Text Gemini analyzes transcript + provides HSK level estimate The Grading Loop python async def grade_session(transcript: str): prompt = """ Rate this Mandarin response on HSK 1-6 scale. Assess: tone accuracy, grammar, vocabulary range. Provide: level estimate + weak points. """ response = await gemini.generate_content(prompt, stream=True) return parse_hsk_level(response) Results - 3-min test - Real-time feedback - Shareable HSK score card - Free (limited sessions) Open source coming soon. Built because I'm a native speaker + voice actor frustrated with generic tools. Try it: tonetutor.tefusiang.com (free for 3 sessions) Curious about the speech-to-text pipeline or tone grading logic? Ask below.

It all started on June 23rd with a casual post about a VPS Manager benchmark. Out of curiosity, I decided to ask the author of the benchmark, Pascal CESCATO Follow Full-stack dev sharing practical guides on WordPress, n8n automation, AI tools, Docker & self-hosting. Always experimenting with new tech to make life easier. , if he had tried Cloudflare's new Workers AI offering—specifically Kimi K2.7, a massive 1-trillion parameter MoE (Mixture of Experts) model that was incredibly cheap ($0.27 per million input tokens) and highly capable at code generation. Pascal was intrigued. He pointed out a brilliant hypothesis: if a model makes significantly fewer mistakes, the total session cost drops dramatically even if the per-token price is higher. He cited GLM 5.2 as a model that self-corrected multiple bugs during verification to achieve 37/37 tests passing. Curiosity got the better of me. I spun up my development environment, wrote a custom agent harness, and ran it on Kimi K2.7 using Cloudflare Workers AI. The V.E.L.O.C.I.T.Y.-OS Series Table of Contents We are building a bare-metal, self-healing operating system running entirely inside the CPU's L3 cache. Here is the roadmap for this 12-part series: Part 1: The Spark — Exposing the "Safe-Room" security leak and building the compiler gate. (You are here) Part 2: The NDA Language — Designing a content-addressed triplet representation to cure context bloat. Part 3: Ditching the Web Stack — Building a native 30MB IDE with 1,500,000x IPC latency drops. Part 4: The Closure JIT — Compiling AST blocks to nested closures and bypassing borrow checker limits. Part 5: JIT Math Optimizations — Replacing division operations with precomputed 16-bit lookup tables. Part 6: x86-64 Assembler & SCEV-Lite — Compiling scalar loops directly to native code in constant time. Part 7: Classic Compiler Passes — Implementing inter-procedural Dead Code Elimination and loop unrolling. Part 8: Reclaiming Ring 0 — Exiting UEFI boot services and transi

I’ve always been fascinated by PDFs. They look simple on the surface. Just a document you can open anywhere but underneath they’re a full layout engine, object graph, drawing model, and archival format all at once. I enjoy that mix of precision and complexity and that is exactly what led me to build PDF::Make (and yes I had some help from Claude LLM). I wanted a fully featured toolkit that could both generate PDFs and let me inspect/edit them programmatically. At the low level, PDF::Make exposes the raw building blocks of the format: PDF objects, pages, the drawing canvas, a parser/reader, and import/merge primitives. This is the layer you reach for when you need fine grained control or want to work with the structure of a document directly. For everyday document creation, PDF::Make::Builder sits on top of that foundation and provides a higher level API. It handles the boilerplate of page setup, fonts, text flow, and layout so you can produce a polished PDF in just a few lines of Perl. The same toolkit is also designed for post-processing. You can open an existing PDF, extract structured text along with its coordinates, and then draw annotations or overlays back onto the page, making it straightforward to build review, QA, or markup workflows on top of documents you didn’t originally generate. This post shows a practical two-step flow: Create a PDF Re-open it, extract text coordinates, and draw border highlights around matched words 1) Create a PDF with PDF::Make::Builder Script: #!/usr/bin/perl use strict ; use warnings ; use PDF::Make:: Builder ; my $pdf = PDF::Make:: Builder -> new ( file_name => ' source_demo.pdf ', configure => { text => { font => { family => ' Helvetica ', size => 12 , colour => ' #222222 ' }, }, }, ); $pdf -> add_page ( page_size => ' Letter ') -> add_h1 ( text => ' PDF::Make blog demo ') -> add_text ( text => ' PDF::Make builds and edits PDF files directly from Perl. ') -> add_text ( text => ' In the next step we extract text coordinates and

I built a free n8n workflow that writes your launch content for you. It broke three times before it worked, and the third break is the only part of this post worth reading. The problem Every time I ship a new digital product, I write the same five things: a short blog intro, a LinkedIn post, an X post, an Instagram caption, and a launch email. Same structure every time, different product. The kind of task that's boring enough to automate but annoying enough that I kept putting it off. So I built Launch Content Pack : an n8n workflow that takes one product description and generates all five, using an LLM node wired up with Claude Code on the customization side. It's free, it's on Gumroad, and the JSON is the whole product — open it, see every node. Why bother when there are 9,000+ free n8n templates already There are. I checked before building this, because there's no point shipping a workflow that already exists for free somewhere else. What's actually missing from most of those templates: nobody validates the nodes. A huge chunk of free n8n templates floating around were generated by someone (often an LLM) guessing at node types and parameters, and they quietly break the moment n8n ships a version update. I used n8n-mcp , a free MCP server, to confirm every single node type, version, and parameter against n8n's actual schema before writing any JSON. No guessing. That sounds like a small difference. It's the reason this post exists. The bug that actually mattered I tested the workflow in n8n Cloud. Two nodes ran clean — green checkmarks, no errors. Then the Code node that's supposed to take the LLM's output and split it into five labeled fields threw: Cannot read property 'text' of undefined My first guess was wrong. I assumed the LLM node's output field was named something other than text — output , maybe, or response — and that I just had the wrong field name in the Code node. Reasonable guess. Also not the actual bug. Here's what was really happening. The OpenAI

Why did I build Aegis Pulse? As always, it started with a simple thought that keeps getting me time and time again: "I should automate this." So, I announced Aegis Stack publicly on Reddit on December 3rd. From that very moment, I became great friends with the Unique Clones / Total Clones & Unique Visitors / Total Views charts in GitHub's analytics page. Due to the nature of aegis-stack, every stack that is spun up will clone the actual repo itself (outside of caching situations, which may vary from user to user). I didn't realize it at the time, but those clone numbers, especially the Unique Clones, would become the most important metric for me to track usage. There's this funny thing that happens when you release an OSS tool. You expect people to say something, maybe tell others, ask questions... just... something... Instead, the person looks at the tool, sees if it makes their life easier, and puts it in their bag of other tools. I know this, because this is me! I never thought about it until I'm on the other side. I had to mentally go through all the tools I had used over the years, and realized I never cared about anything other than the tool itself. And if it didn't work, I would try to make it work, and if not, just move on. Time is money, and all of that. All of that is to say, clones are something I have been tracking since day one. Now... GitHub has a 14-day rolling window period in which they have daily values, and the 14-day rolling totals. And when I say 14 days, I mean it. That's all you get, and it's on you to keep track of everything outside of that. Fair enough. Thus began the daily ritual of going and grabbing the latest numbers from the previous day, and pasting the data into 3 separate AI chats: ChatGPT, Claude Opus, and Google Gemini. I figured that since I was already storing all of this data, I might as well see what type of insights I could get from these chats (which were preloaded with enough context to know what's going on). It was a great

A few weeks back I shared some early Zen code examples. Since then, a lot has changed. We're now at v1.1.1 and the language actually has real tooling. What's new: Full CLI with package management zen publish - publish packages directly from CLI zen install - install packages from the registry zen list - browse all published packages with pagination Language improvements Struct support with literals and returns Regex with POSIX ERE ( matchRegex ) File I/O with binary support FFI bindings to C functions 162 stdlib functions across math, strings, fs, os, http, crypto, path utilities Package Registry (v1.0.0) JWT-based authentication GitHub-hosted packages Support for both runnable apps and libraries Semantic versioning The reactive variables concept from the first post is still there (that was my favorite feature), and now you can actually write real programs and share them with the community. Full docs: https://jishith-dev.github.io/zen-doc/site/ Install: curl -fsSL https://raw.githubusercontent.com/jishith-dev/Zen/main/install.sh | bash Next up: HTTP server APIs, better imports, and whatever the community asks for. Open to feedback and collaborators 💻 ✨ zen #programming #compiler #llvm #packagemanager #opensource #programminglanguage

Figma shipped native Motion. A real animation timeline, right inside the file. When that landed, a lot of people emailed me some version of the same question: "is MotionKit dead now?" Fair question. My honest first reaction was a quiet "...maybe." But the more I used native Motion, the clearer it got — it's genuinely good, and it's not trying to be everything. No physics. No frame-by-frame. No Lottie export. No morphing. So the move was never to compete with it. The move was to bridge to it — let the two tools hand work back and forth, and let MotionKit be the power layer that does the stuff native Motion can't. So that's what this update is. A two-way bridge between MotionKit and Figma's native Motion. Here's everything it does, and exactly how to use it. The short version Four moves, one little control in the header: Import native Motion into MotionKit as real, editable keyframes Live sync (read-only by default) so changes in Figma Motion flow into MotionKit as you work Link for export so your native Motion renders inside a Lottie without duplicating anything Push MotionKit keyframes back into native Motion — including motion you baked from the physics engine And the headline trick: bake a real physics drop in MotionKit, then push it into Figma Motion as native keyframes. Native Motion has no physics engine. Now it kind of does. First, find the bridge Look at the top-right of the toolbar, next to the Pro star. There's a small badge: the MotionKit diamond, an arrow, and the Figma logo . That little arrow is the status. You don't have to open anything to read it: faint dotted line → not connected arrow pointing into MotionKit → reading from Figma, live, read-only arrows on both ends → two-way, MotionKit also writes back If there's native Motion sitting on the current frame but you haven't connected, you'll see a small purple dot on the Figma side — that's "hey, there's something here to import." Click the badge to open the bridge. That's the whole mental model. Dire

Most job search tools focus on submitting more applications. I wanted to solve a different problem: reaching the people actually making hiring decisions. So I built PitchHired , an AI-powered platform that helps job seekers find hiring managers, generate personalized outreach emails, review them with AI, and send them from their own Gmail account on a business-hours schedule. The goal isn't to replace the job search, it's to remove repetitive work while keeping the candidate in control. I also chose a one-time credit model instead of monthly subscriptions because job seekers shouldn't have to keep paying while they're between opportunities. PitchHired is still evolving, and I'd genuinely appreciate feedback from fellow developers. What features would you want in a tool like this, and what would make you trust (or not trust) AI-assisted job search?

I'm building TTT -- a terminal text editor and IDE written in Go. Single binary, zero config, runs anywhere. Think VS Code but in your terminal. It has syntax highlighting, LSP integration, a plugin system, an integrated terminal, git integration, etc... The source is on GitHub and I develop it with Claude Code as my pair programmer. This is the story of how a frustrating limitation turned into something genuinely useful: a built-in scripted interaction system that lets AI agents (or anyone) drive the editor like Playwright drives a browser. The problem I was deep in revamping the widget system and building out a Lua plugin API. Phases of work stacking up -- widget rendering, panel support, tree views, input fields, command registration, keybinding hooks. The kind of work where you need to see what's happening. Click a tree node, check if it expands. Open a panel, verify focus moves correctly. Run a plugin, confirm the dialog appears. Here's the thing: Claude Code can run shell commands and read files. It cannot interact with a live TUI session. The editor launches, takes over the terminal, and that's it -- Claude is blind. Step 1: tui-use (what we had) The project already had functional tests using tui-use , a JavaScript library that drives a real terminal binary. It can type, press keys, wait for text to appear, and take snapshots: const tui = await start ( " bin/ttt " , [ " test-file.go " ]); await tui . waitFor ( " test-file.go " ); await tui . exec ( " editor.joinLines " ); const screen = await tui . snapshot (); expect ( screen ). toContain ( " joined line " ); This works. But it's slow -- each test spawns the binary, waits for screen renders, polls with timeouts, and parses terminal escape codes. And critically, it can't click . Mouse events aren't supported. For a widget system with tree views, buttons, and split panels, that's a dealbreaker. Step 2: Debug commands (the workaround) So we added a Debug: Simulate Click command to the editor itself. Open the co

Hey DEV community! 👋 I've been building web apps for a while, and I noticed there was no good place to discover and rate web-based OS projects — those cool browser-based operating systems you can run without installing anything. So I built Web OS Community 🎉 What is it? A platform where you can: 🔍 Browse web-based OS projects (Windows XP, Ubuntu, macOS clones, and more) ⭐ Rate your favorites with a global rating system 🏷️ Filter by tags (webos, demo, linux, macos, windows...) 📤 Submit your own web OS project via GitHub PR Why I built this The existing resources were scattered — some projects on GitHub, some on random personal pages. I wanted a central hub where developers could showcase their work and users could find these cool experiments easily. Tech stack Frontend: Vanilla JS / HTML / CSS (no frameworks, keeping it lightweight) Backend: Supabase (PostgreSQL + RLS policies) Auth: Custom RPC-based authentication Hosting: GitHub Pages + Cloudflare Workers Some features Global rating system (one vote per user per project) Admin panel for managing submissions Tag-based filtering Dark mode UI 🌙 Check it out! 🔗 web-os-community.tfhy5321.workers.dev If you have a web OS project, feel free to submit it! PRs are welcome 🙌 What web-based OS have you seen that blew your mind? Drop it in the comments!

Every side project starts the same way. -Generate an OpenAI key. -Add it to .env. -Write a...

Every developer hates writing READMEs. It's boring, repetitive, and always gets skipped. So I built ReadmeAI — describe your project, AI writes the README instantly. What it does Fill in project name, description, tech stack, features AI generates a complete professional README.md Switch between Raw and Preview tabs to see rendered markdown One click copy Tech Stack Next.js + Tailwind CSS Groq API (openai/gpt-oss-120b) Deployed on Vercel Why I built it (Write 2-3 sentences personally — mention the challenge, that you're a student builder, makes it relatable) Live link https://readmeai-three.vercel.app/ Built this in a day as part of my 30-day AI tools challenge. Would love feedback from the dev community!

Most poker solvers answer one question very well: given a single hand and a single decision tree, what is the equilibrium strategy? (Yes, there is subgame solving, node locking, and plenty more — but the default frame is still one hand, one equilibrium.) I kept getting stuck on a different one. What if the same kind of spot shows up over and over, and a player can commit to a fixed strategy across those repetitions? In a few toy games I had a hunch, worked out by hand, that committing to a fixed strategy could change its value relative to the one-shot picture. I wanted a tool that could make that commitment value precise — to actually analyze it rather than just believe it. (Whether any of this rises to a repeated-game equilibrium is a much stronger claim, and one I am deliberately not making here.) I'm still learning software engineering, so until recently I couldn't implement this — I was stuck reasoning about toy games on paper. AI tooling made the analysis feasible, so I finally started building it: repeated-poker-analysis . It's a small research project: write one narrow model down, run small examples, and record what the model does and doesn't justify. What repeated-poker-analysis is It is an experimental Python toolkit for small abstract poker games. The current MVP covers: fixed Hero commitment candidates, exact Villain best-response diagnostics in small finite trees, candidate generation and filtering, T_deadline , an economic adaptation deadline, local T_detect , an observable-distribution sensitivity estimate, analysis reports and Markdown summaries. It is small on purpose. It is not a full solver and it is not wired to real solver ranges. It starts from one toy game — a river spot — that is tiny enough to inspect and test by hand. That toy spot is one where showdown always chops but rake still bites. In a single-hand view, putting more money into a raked pot can be locally unattractive. Across repeated occurrences the same spot raises a commitment questi

An innovative Moroccan platform for finding, renting, and selling real estate, offering a simple and seamless experience tailored to the local market. Challenge Launch Sarout.ma, an innovative Moroccan platform dedicated to searching, renting and selling real estate, on an ultra-competitive market dominated by a few historical players often criticized for dated ergonomics and uneven listing quality. The challenge: build an intuitive, modern real estate marketplace able to connect individual owners, agencies and tenants across all of Morocco — Casablanca, Rabat, Marrakech, Tangier, Agadir — with clear navigation and smart search. It also required enriched, geolocated listings updated in real time, and a journey differentiated by user profile (searcher, owner, professional agency). Solution Development of a site with a clean, fully responsive interface, designed mobile-first since most real estate searches in Morocco happen on smartphones. Integration of advanced dynamic filters (city, neighborhood, price, surface, number of rooms, property type, furnished/unfurnished) with instant result refresh. Listing management via a complete owner dashboard: creation, editing, view statistics, photo management with multi-upload and automatic compression, scheduling of paid promotions. Each property page has an SEO-optimized URL, rich descriptive content, precise geolocation on an interactive map, and the option to directly request a viewing. SEO architecture focused on local ranking: category pages per city and neighborhood, Schema.org RealEstateListing markup, dynamic sitemap. Email alert system for saved searches, listing moderation, and a professional agency dashboard for premium accounts. Results A high-performing, accessible real estate portal that significantly simplifies property search for individuals and strengthens listing visibility across Morocco. The interface fluidity stands out in a market where competition remains rough around the edges. Steady growth in publishe

After months of building in public, is live on Product Hunt today! 🎉 The problem Every dev team I've worked with ends up in the same trap: Jira is too heavy and slows everyone down with ceremony, while Trello/Notion are too light and can't actually tell you if your sprint is on track. Nobody had a tool that combined real project management with AI that actually understands developer workflows. So I built one. What is Rahnuma.io? Rahnuma.io is an AI-powered DevOps platform that sits where project management meets your actual engineering workflow: 🧠 AI task generation — describe a feature in plain English, get a structured task with subtasks 📊 Deadline risk forecasting — a live risk score (0–100) built from time risk, blockers, and completion rate, so you know a sprint is in trouble before it blows up 🗂️ Kanban + sprints — drag-and-drop boards, WIP limits, burndown charts, story points 🤖 AI sprint retros — auto-generated "what went well / what didn't / action items" 🔗 GitHub & Bitbucket integration — see commits next to the tasks they belong to 📈 Reports that don't require a translator — including an "Explain to My Boss" button that turns your sprint into a plain-English executive summary 🔔 Slack notifications for task creation, assignment, and comments 🧾 Client portals — shareable, printable progress reports for non-technical stakeholders Why it's different Most "AI project management" tools just bolt a chatbot onto a Trello clone. AI is wired directly into the data model — it knows your sprint history, your velocity, your blockers — so the forecasts and summaries are grounded in your actual project state, not a generic prompt. Tech under the hood Next.js 15 (Turbopack) · TypeScript · Prisma + PostgreSQL · Clerk auth · Polar billing · Redis · xAI Grok with Groq fallback for AI · Server-Sent Events for realtime sync. Try it It's free to start, no credit card required. I'd love your feedback — especially from anyone who's felt the Jira-is-too-much / Trello-is-too-littl

I wanted to tell my girlfriend 'I missed you today' in Farsi and have it sound like something a person would actually say, not a phrase pulled from a travel guide. Every tool I tried — Google Translate, DeepL — gave me one answer. No register. No note on whether it was too formal for a text message or too casual for a letter. Just a string of words and the implication that language has one correct answer per sentence. So I built konid: it returns three options for anything you want to say, ordered casual to formal, each with the register explained and the cultural nuance between them described. It also plays audio pronunciation through your speakers directly, using node-edge-tts — no API key, no copy-pasting into a separate tab. The interesting engineering constraint was deployment target. I wanted this to live where I already work, not in a separate browser tab I forget to use. That meant MCP. A single MCP server running at https://konid.fly.dev/mcp now serves four clients without any client-specific code: # Claude Code claude mcp add konid-ai -- npx -y konid-ai # ChatGPT (Developer mode, Actions) # endpoint: https://konid.fly.dev/mcp Cursor, VS Code Copilot, Windsurf, Zed, JetBrains, and Claude Cowork all connect the same way. The server doesn't know or care which client called it. The output structure for a query like 'I missed you today' in Japanese looks roughly like this: Option 1 (casual): 今日会いたかった Register: intimate, fine for close friends or a partner Note: dropping the subject is natural here; adding あなたに would feel stiff Option 2 (neutral): 今日、あなたのことが恋しかったです Register: polite, appropriate for someone you're close to but addressing respectfully Option 3 (formal): 本日はお会いできず、寂しく思っておりました Register: formal written Japanese; would be unusual in a personal context The nuance comparison is the part I couldn't get anywhere else. Knowing that option 3 exists and that you would almost never use it for a personal message is actually load-bearing information if you're l

Most people lose hours pretending to work or study. I was one of them. I kept setting Pomodoro timers and ending up scrolling Twitter during breaks. That's not rest. That's just a different kind of distraction. So I built Mognota — a free wellness companion for screen workers. The Problem You don't have a discipline problem. You have a system problem. Your brain has a hard biological limit. Sustained attention peaks at 20-45 minutes before quality drops sharply. Long unfocused hours are not work — they are the feeling of work. The solution isn't more willpower. It's intentional recovery. What I Built Mognota pairs a Pomodoro timer with 50+ guided wellness activities: 👁️ 20-20-20 eye break reminders 🫁 Guided breathing & 7 pranayama techniques 🧘 Desk yoga, HIIT, Tai Chi, stretches 🎵 Binaural beats & ambient soundscapes 🧠 Meditation & NSDR protocols 📓 Gratitude journal, mood tracker, brain dump 🎮 Sudoku, sliding puzzle, fractal explorer The Technical Part This is what dev.to might find interesting: Pure HTML, CSS, vanilla JS — zero frameworks Everything in a single HTML file All 8 notification sounds synthesized with Web Audio API localStorage only — nothing leaves your device Works offline once loaded 109+ languages supported No npm. No build step. No dependencies. Just open and use. Try It 👉 https://mognota.com/ Completely free. No account. No ads. Forever. Would love brutal honest feedback from this community.

Building a real-time crypto trading bot sounds like a weekend project — until exchange APIs return cryptic errors, WebSocket connections drop mid-trade, and rate limits turn your strategy into a debugging nightmare. After building my own bot from scratch, I learned that reliability is what separates a hobby script from a system that actually survives in production. This guide walks through the entire process: modular bot architecture, a real-time trading loop, plug-in strategies, backtesting, paper trading, and deployment to a $5 VPS — with production reliability patterns baked in from day one. Full source code included — the free AlgoTrak Backtest Lab on GitHub has 5 classic strategies, a complete backtesting engine, and Jupyter notebooks to get started immediately. Architecture Overview Before writing code, here's the modular structure we'll build: crypto_bot/ ├── strategies/ │ ├── rsi_strategy.py │ ├── macd_strategy.py │ └── ... # Plug in your own ├── core/ │ ├── trader.py # Data fetching + order execution │ └── logger.py # File + DB logging ├── config/ │ └── settings.json ├── cli.py # Entry point ├── bot.py # Main loop └── logs/ Each strategy is a standalone Python class. The trader handles exchange communication. The CLI lets you switch between strategies, symbols, and modes (paper vs live) without touching code. Real-Time Trading Loop Here's the core loop that runs every candle interval: while True : df = fetch_ohlcv ( symbol , interval ) signal = strategy . evaluate ( df ) if signal == " BUY " : trader . buy ( symbol , quantity ) elif signal == " SELL " : trader . sell ( symbol , quantity ) sleep ( next_candle_time ()) Three key points: fetch_ohlcv() pulls the latest OHLCV candle data from the exchange Your strategy evaluates the last N candles and returns a signal Orders execute only on valid signals — no guesswork Modular Strategy Example (RSI) Strategies follow a simple class interface. Here's a complete RSI strategy: import pandas as pd import pandas_ta a

Today I launched Beach Day API , a developer API for real-time beach, ocean, water quality, advisory, amenity, access, and condition data. The goal is simple: make it easier for developers to build apps and tools around beach conditions without having to manually gather data from scattered sources. Beach Day API currently supports beaches across the United States and Australia , and returns structured JSON that can be used in travel apps, weather apps, surf tools, tourism websites, hotel and resort platforms, map-based search experiences, local discovery apps, and coastal safety dashboards. What the API includes Beach Day API can provide data such as: Beach profiles GPS and location data Ocean and weather conditions Water quality grades Advisories and closures Amenities Access details Beach-specific safety and visitor information A proprietary Beach Day Score The Beach Day Score is designed to give developers a fast way to surface whether a beach looks like a good choice for visitors on a given day. Why I built it Most weather APIs are broad. They can tell you temperature, wind, rain, or general conditions, but they usually do not answer the real user question: “Is this a good beach day?” That question depends on more than weather. It can involve water quality, advisories, closures, ocean conditions, amenities, beach access, and the actual visitor experience. Beach Day API is built around that more specific use case. Example use cases Some things developers could build with it: A beach finder app A surf or coastal conditions app A hotel or resort beach conditions widget A local tourism guide A travel planning tool A map-based beach discovery experience A safety dashboard for advisories and closures A recommendation engine for nearby beaches Built for simple integration The API uses API-key authentication and returns clean JSON responses. I wanted it to be straightforward enough that a developer could start testing quickly and then build it into a real product withou