Every product on this page was designed, researched, and engineered by our in-house team of specialists. From high-traffic editorial platforms developed with content strategists, to scientifically-validated cognitive assessment tools built with psychologists. These are real products with real users, built to the highest standards without shortcuts.
Production web platforms serving real audiences, built on robust backend infrastructure and deployed continuously.
When Notes Fly is a high-traffic editorial magazine developed in partnership with professional writers, editors, and content strategists. Dedicated to the life of the mind, covering thinking, learning, technology, culture, and the skills that define modern professional life, every article is crafted to go deeper than a typical blog post, combining research-backed analysis with prose that a curious generalist can follow. The platform organises its content into six primary topic areas: Concepts, Culture, Explainers, Ideas, Technology, and Work Skills, each subdivided into ten focused subtopics, giving readers a structured but exploratory way to navigate a large and growing library of pieces.
Behind the scenes, the platform runs on a full Go/Gin REST API server, PostgreSQL 15, Redis caching for performance at scale, and Docker-based deployment coordinated by Nginx. The architecture follows a clean separation between the API layer and the frontend, with authenticated admin endpoints, subscriber management, a GDPR-compliant cookie consent system, and a full-text search engine across the article library. The Kalenuxer build system compiles the frontend into optimised, minified static assets served through Nginx, keeping page loads fast for readers worldwide.
When Notes Fly is built for readers who want more than surface-level takes, people who read to think, not just to stay informed. It is also the flagship product that validates every Kalenux technology decision in production, from the build pipeline to the deployment workflow.
Whats Your IQ is a scientifically-grounded cognitive assessment platform developed in collaboration with psychologists and cognitive science researchers. Unlike the single-score tests that populate most of the web, our platform structures its assessments around five distinct cognitive domains: verbal reasoning, spatial reasoning, numerical ability, logical deduction, and pattern recognition, and reports a separate score for each. This approach was validated with our research partners to ensure the results provide meaningful, interpretable insight into cognitive strengths rather than a single arbitrary number.
Every question bank was developed and reviewed by specialists in psychometric assessment, with calibrated difficulty levels and domain-specific weighting to produce results that are consistent, reproducible, and comparable across different user sessions. Tests are delivered with full randomisation at both the question and answer-option level, so no two sessions are identical, a design principle insisted upon by our psychometric advisors to prevent score inflation through memorisation.
The platform serves users across 15+ language regions, with full localisation of all UI text, instructions, and result descriptions. It is designed for students, professionals, and anyone curious about their cognitive profile, a global audience that benefits from a clean, fast, no-barrier experience that works on any device without installation or account creation.
File Converter Free is a browser-based file conversion platform built on a single, non-negotiable principle: your files never leave your device. Every conversion operation - whether you are converting a Word document to PDF, reformatting an image from PNG to WebP, or changing an audio file from MP3 to OGG - runs entirely inside the browser using JavaScript and WebAssembly. There is no server receiving your data, no upload progress bar, and no third-party service handling sensitive documents. The file goes in, the converted file comes out, and nothing in between touches a network connection.
This architecture is made possible by compiling format conversion libraries to WebAssembly, allowing code that would traditionally run on a server to execute at near-native speed inside the browser sandbox. The platform uses the browser's File API to read input files directly from disk, processes them through the appropriate WebAssembly module, and writes the output back through a generated download link. Because processing happens on the user's own hardware, conversion speed scales with the user's device rather than with server load - a fast local machine converts faster, and there is never a queue to wait in.
The platform is designed for anyone who has ever felt uncomfortable uploading a confidential document to an online converter - legal professionals, medical staff, journalists, or simply privacy-conscious individuals who do not want their files on a stranger's server. No sign-up, no subscription, no file size limit imposed by server costs. Just open the page and convert.
QR & Barcode Tool is a comprehensive web platform for generating and scanning QR codes and barcodes of all common formats, built as a Progressive Web App so it installs on any device and works fully offline. The generator side supports every practical QR code data type - URL, plain text, contact card (vCard), WiFi network credentials, email address, phone number, and SMS - and produces output in PNG, SVG, and PDF formats so the result is useful whether it ends up on a website, a business card, or a printed flyer. Custom colours, logo embedding, and error correction level selection give designers the control they need for branded code generation.
The scanner side uses the device camera through the WebRTC API and runs a real-time decode pipeline that recognises QR codes, Code 128, Code 39, EAN-13, EAN-8, UPC-A, UPC-E, and Data Matrix formats without requiring any app installation. Scan results are logged to a local history with timestamps and the raw decoded payload, making it practical as a professional scanning tool for inventory, logistics, or event check-in workflows. The batch generation feature allows creating multiple codes from a CSV upload in a single pass, with bulk download as a ZIP archive.
Because the platform is a PWA, it adds to the home screen on Android and iOS, behaves like a native app with a full-screen interface, and caches all assets for reliable offline operation. This makes it equally useful in warehouse environments with poor connectivity, at outdoor events, or anywhere a browser-based tool needs native-app reliability.
Down Under Cafe is a specialty coffee and cafe discovery platform built for people who care deeply about where they work and drink. The platform combines curated editorial content with a searchable, filterable cafe directory across multiple cities, covering specialty roasts, espresso quality, work-friendliness (wifi, power, noise level, table space), and atmosphere. Every listing is backed by structured data built up through community submissions, editorial review, and ongoing refinement.
The platform runs on a Go/Gin API backend with PostgreSQL, a Redis-backed caching layer, and a Kalenuxer-built static frontend optimised for SEO. Deployment is shared on the When Notes Fly production server behind Nginx. A full admin panel handles cafe submissions, moderation, media uploads, and scheduled content rebuilds. Every venue profile and article is written and reviewed by hand.
Strange Animals is a content platform dedicated to the most bizarre, fascinating, and incredible creatures on Earth. Covering everything from deep-sea oddities and ancient extinct giants to venomous insects and shape-shifting reptiles, the platform delivers expert-written articles, interactive tools, and curated image galleries across six major animal categories. Built for viral reach and topical authority in the wildlife niche.
The platform runs on the same proven Go/Gin API stack with PostgreSQL and Redis, powered by a Kalenuxer-built static frontend optimised for search engines. Deployed on the file-converter-free.com server with its own isolated database and API containers. Features include an animal quiz, species identifier, size comparison tool, interactive world map, random animal generator, and a searchable gallery, all designed to maximise engagement and dwell time.
Evolang is a professional writing resource platform built for anyone who needs to write clearly and communicate effectively. The site covers email templates, letter templates, business writing guides, grammar and punctuation references, communication skills content, and AI writing tool reviews. Every piece of content is expert-written with practical, ready-to-use examples.
The platform is structured around topic silos for maximum SEO authority, with 90 articles covering six major writing categories. Built on the same proven Go/Gin API stack with PostgreSQL and Redis, powered by a Kalenuxer-built static frontend. The architecture prioritises fast load times, clean URLs, and structured content that ranks well in search.
Corpy is a business formation decision platform with expert-written guides on starting companies worldwide. Whether you are an entrepreneur evaluating jurisdictions, a digital nomad choosing where to incorporate, or a global business expanding into new markets, Corpy provides country-specific formation steps, corporate tax breakdowns, and free zone comparisons to help you make informed decisions.
The platform covers company formation procedures, corporate tax rates and structures, business law overviews, free zone and incentive directories, and multi-country cost comparison tools. All content is expert-written and structured for clarity, with step-by-step timelines and compliance checklists. Built on the proven Go/Gin API stack with PostgreSQL, Redis, and a Kalenuxer-built static frontend.
Pass4Sure is a certification exam prep and career success platform built for professionals who need to pass. The site covers AWS, Azure, CompTIA, Google Cloud, ITIL, and more, with expert-written study guides, domain breakdowns, practice test strategies, and honest advice on what actually matters for each certification. The content is organised into focused silos so readers can go deep on the credentials that matter to their career.
Beyond certifications, the platform extends into interview prep and career strategy, covering behavioural frameworks, technical interview patterns, visa interview guidance, and cert ROI analysis. Built on the same Go/Gin backend and Kalenuxer frontend as Down Under Cafe and When Notes Fly, with a full content management system, subscription layer, and a deploy pipeline running on its own VPS.
Published Android applications built natively with Java and Kotlin. Each app solves a specific problem that mainstream apps handle poorly - too many permissions, too much cloud dependence, too little respect for the user's privacy and storage.
A fully offline reading and editing application that treats both PDF and EPUB as first-class formats rather than bolting one on as an afterthought. The app opens large documents quickly with progressive page rendering, so you are reading within seconds rather than waiting for the whole file to load into memory. Annotations, highlights, and bookmarks are stored locally alongside the document and survive app restarts without requiring any cloud account. Three built-in reading themes - white, sepia, and night - cover every lighting environment, and adjustable font size and family settings make the reading experience genuinely comfortable for extended sessions. The text-to-speech integration reads any document aloud with sentence-level highlighting so you can follow along, turning commute time into reading time. For EPUB files, the table of contents panel gives instant chapter-level navigation, and the in-document search locates specific passages across the entire book in under a second.
A multi-format scanner with a built-in generator that opens directly to the camera viewfinder with no splash screen delay. The real-time scan engine uses the device camera to automatically detect and decode QR codes, Code 128, EAN-13, EAN-8, UPC-A, and UPC-E barcodes without requiring the user to select a format manually. Every successful scan is added to a local history log with a timestamp and the full decoded payload, so you can go back to a scan from days ago without re-scanning anything. Results can be shared directly to any app, opened as a URL, copied to clipboard, or saved as a contact in a single tap. The built-in generator produces QR codes for URLs, contact cards, WiFi network credentials, and plain text, which can be shared as an image or displayed on-screen for another device to scan. The app requests only the camera permission it actually needs and makes no network requests beyond what the user explicitly triggers by opening a scanned URL.
A device diagnostics tool that gives you the information your manufacturer's settings app deliberately withholds. The battery module reads the current charge level, battery health status, estimated charge cycle count, and real-time temperature, presenting the data in a clear timeline so you can see whether your battery is degrading faster than expected. The performance module displays live CPU usage per core, total RAM allocation and free memory, and storage breakdown by category - apps, media, documents, system - so you know exactly what is consuming space before you start deleting things. The sensor health panel tests the gyroscope, accelerometer, and compass by running each through a short calibration routine and reporting whether the readings are within normal range, which is useful when diagnosing motion-related issues in games or navigation apps. A built-in network speed test measures download and upload throughput on both WiFi and mobile data, and a device benchmark runs a standardised compute workload to give a single performance score you can compare across devices or across time on the same device.
A mobile coding assistant built for developers who switch between their desk and their phone and do not want to lose momentum. The core of the app is a snippet library containing over 500 hand-curated code snippets across more than 20 programming languages - JavaScript, TypeScript, Python, Go, Rust, Java, Kotlin, Swift, SQL, Bash, and more - each with a plain-English explanation of what the snippet does and when to use it. Snippets are searchable by keyword, filterable by language, and copy to clipboard in one tap. The documentation browser provides offline syntax reference for the most commonly used standard libraries, so you can look up how a language feature works without burning mobile data on a documentation website. The regex tester lets you write and test regular expressions against sample input with live match highlighting, which is useful when you cannot remember whether a pattern uses a capturing group or a non-capturing one. Additional utilities include a JSON and XML formatter and validator, a base64 encoder and decoder, a URL encoder and decoder, a Unix timestamp converter, and a color picker that outputs hex, RGB, and HSL values for use in CSS or design tools.
An encrypted file security application that uses AES-256 encryption to protect files and folders on the device with no cloud dependency whatsoever. The encryption and decryption operations happen entirely on-device using the Android Keystore system, which means the encryption key never leaves the hardware security module and cannot be extracted even if the device is physically compromised. The app unlocks with a PIN or biometric authentication depending on the device's capabilities, and it supports a hidden vault mode that presents a functional calculator interface to anyone who opens the app without the correct unlock sequence - a useful feature for protecting sensitive content in situations where showing a lock app would itself attract unwanted attention. The secure photo vault imports photos and videos from the gallery, encrypts them, and deletes the originals, so the files no longer appear in any gallery app or backup. Encrypted notes provide a private text store that sits outside the standard notes ecosystem. Import and export of encrypted containers allows moving a vault between devices over a local cable without any file ever being decrypted in transit.
A Node.js build pipeline that replaces the full stack of separate tools - template engine, CSS preprocessor, JS bundler, image optimiser, deployment script - with a single coherent system. Every Kalenux web product is built and deployed with it.
Kalenux designs and builds web platforms, mobile apps, and custom tools to the same standard as every product on this page. Direct communication, no outsourcing, and full ownership of everything delivered.