How a Caffeine Tracker Uses Decay Math to Show What's Still in Your System

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A developer built a manual caffeine tracker that estimates residual caffeine in the body using an exponential decay formula based on a default five-hour half-life. Unlike a simple daily total, the tool sums the decayed residuals of every logged drink, meaning a late-night coffee from the previous day can still show up in the current estimate. Records are kept for 48 hours rather than reset at midnight, preventing the misleading scenario where a low daily total masks significant leftover caffeine. The tracker includes a Chart.js projection of residual levels over the next 24 hours, sampled at 30-minute intervals, with a configurable 50 mg sleep threshold line and a separate 400 mg daily reference. The project's key design principle is keeping dose, time, half-life, and display thresholds as distinct variables rather than collapsing them into a single opaque figure.

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As AI Benchmarks Age and Saturate, Measuring True AI Progress Gets Harder

The launch of GPT-6 Astra, accompanied by NVIDIA CEO Jensen Huang declaring on X that 'AGI has arrived,' has reignited debate about how capable AI systems have truly become. Experts and developers quickly split between excitement and concern, with many questioning whether such milestones signal the end of software engineering as a profession. However, a closer look at AI evaluation reveals a deeper issue: benchmarks used to measure model progress can become outdated, saturated, or methodologically inconsistent over time. Astra's own system card acknowledges that some older evaluations are being retired and newer ones are adopting more realistic testing conditions, meaning a higher score does not always reflect genuinely broader capability. While AI will undoubtedly reshape software development, core engineering responsibilities such as system design, security, and architectural decision-making remain distinctly human concerns that raw benchmark numbers do not address.

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ProgrammingDEV Community ·

How to Build an AR Fallback Governor That Protects User Camera Privacy

A developer tutorial on DEV Community outlines how to build an application-side fallback governor for Tencent RTC's Beauty AR feature, ensuring avatar failures do not silently expose a user's camera feed. The core problem addressed is that when AR effects fail due to device overheating, asset loading errors, or OS interruptions, most apps default to the raw camera — a privacy-violating substitution. The proposed governor enforces a tiered degradation ladder: quality avatar, performance avatar, sticker, and finally a paused state if camera consent has not been explicitly granted. It adapts to device capability tiers, avoids oscillating between profiles, and rejects stale async events to prevent race conditions. The tutorial argues that consent must be collected separately for each presentation mode, since switching from an avatar to a live camera feed is a fundamentally different act, not merely a quality reduction.

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ProgrammingDEV Community ·

JQuickCurl Library Simplifies Multipart File Uploads in Java Using curl Syntax

JQuickCurl is a Java library that lets developers send multipart HTTP file uploads using familiar curl -F flag syntax, eliminating the need to manually configure OkHttp or RestTemplate multipart bodies. The library interprets the @ symbol convention to distinguish file paths from plain text form fields, then builds the corresponding multipart request over OkHttp automatically. Developers can upload single or multiple files, mix files with form metadata, and inject dynamic file paths at runtime using variable substitution in annotated interface methods. The approach keeps HTTP implementation details out of service code by expressing upload logic as a standard curl command string in a Java annotation. The library's behavior was demonstrated against the httpbin echo endpoint, which confirmed correct multipart transmission by returning uploaded file data in its response.

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ProgrammingDEV Community ·

Developer Builds Interactive Lab Site to Host Experiments Beyond a Standard Portfolio

A developer known as joacod has launched 'joacod Lab', a personal web platform designed to host interactive experiments, prototypes, and small tools that don't fit the format of a traditional portfolio or blog. Unlike his static blog, which publishes finished learnings, the Lab is built to support dynamic work such as GPU playgrounds, material studies, and browser-based games with leaderboards. The platform uses a shared shell for navigation and infrastructure while allowing each experiment to maintain its own interface, rendering stack, and interaction model. The developer intentionally avoided over-engineering a plugin framework, following a principle of sharing infrastructure without dictating what each experiment must be. The project evolved from an early dashboard concept into a more flexible architecture that treats each entry as an independent work-in-progress rather than a finished product.

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