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I'm 16, from Pune, India. For the past couple of years I've been building O-AI — a fully local AI desktop assistant. No cloud. No API keys. No data leaving your machine. Everything runs on your own GPU. Why I built it Every AI assistant I tried sent data somewhere. ChatGPT, Copilot, Gemini — all cloud. I wanted something that felt like JARVIS from Iron Man: smart, fast, personal, and private. So I built it from scratch. What O-AI can do Core engine: Runs LLMs fully on-device via llama.cpp / Ollama (zero internet required) Self-learning core — extracts facts from every conversation and stores them permanently Fine-tuning pipeline — train the model on your own data, locally Voice & language: Voice control in English, Hindi, and Marathi via Whisper (running locally) Responds in whatever language you speak Modes: JARVIS mode — arc-reactor HUD, 4 reactive states, British-male voice, "sir" persona Take Over PC mode — full desktop automation Animated floating desktop pet (4 types, draggable, reacts to voice) 30+ automation fast-paths: open apps, search the web, control media, screen vision, run code, edit files, cursor control, social media steps, clipboard ops... Multi-step agent system: plan → execute → verify loop with 14+ step types (web_search, fetch_url, read_screen, run_code, edit_file, open_social, and more) Stack Backend: Python (Flask IPC + agent core) Frontend: Electron + vanilla JS LLM: llama.cpp / Ollama Voice: Whisper (local) + Edge TTS / neural voice Vision: PIL + screen capture The hardest bugs "Says done but isn't" — Early versions reported success even when an agent step failed. Fixed by building a proper outcome verifier that reads the actual result, not the plan. The "opens a random video" bug — Asking the agent to play something would open random YouTube videos. Root cause: the plan validator wasn't catching placeholder URLs like [video_url] . Fixed with a universal content guard on all plans. GPU offloading on Windows — Getting all 32 layers onto the

csv-pipe: read and write CSV in TypeScript, several times faster than papaparse Myroslav Martsin Myroslav Martsin Myroslav Martsin Follow Jun 22 csv-pipe: read and write CSV in TypeScript, several times faster than papaparse # javascript # typescript # webdev # node 1 reaction Add Comment 2 min read

TL;DR — If your backend already uses OpenTelemetry, you can send traces and logs to Sentry by changing a few environment variables. No SDK swap, no instrumentation rewrite. Point your OTLP exporter at Sentry’s endpoint, add the Sentry SDK on the frontend for browser context, and you get one connected trace from click to backend span. You already instrumented the backend with OpenTelemetry. Your services emit spans. Your teams know the OTel APIs. Maybe you already run a Collector. So when you start evaluating Sentry, the obvious question is: Do you need to replace your OpenTelemetry setup with the Sentry SDK? No. The practical answer is usually: keep OpenTelemetry where it already works, add the Sentry SDK where it gives you more application context, and send OpenTelemetry Protocol (OTLP) events to Sentry. For a web app, that often means using the Sentry SDK on the frontend for browser tracing, errors, logs , Session Replay , and source maps, while keeping OpenTelemetry on the backend for existing service instrumentation. One scope note: OTLP can carry traces, logs, and metrics. At this moment, Sentry’s OTLP ingest supports logs and traces, not metrics. We’re considering adding support for them in the future. The important part is separating two decisions that often get lumped together: How traces stay connected across frontend and backend. How backend OTLP events are exported to Sentry. Once you separate those, the architecture gets a lot easier to reason about. Sentry vs OpenTelemetry is the wrong question The first decision is trace linking. If a user clicks a button in your React app and that click triggers a backend request, the frontend and backend need to agree on the same distributed trace context. In this example, the Sentry frontend SDK sends W3C traceparent headers (configurable through the propagateTraceparent option), and the OpenTelemetry backend continues the trace. That linking is handled by the frontend SDK configuration: Sentry . init ({ integration

10 Things Nobody Tells You About process.env I've burned myself on most of these so you don't have to. Here's what I wish someone had told me early on. 1. Keys are case-sensitive on Linux, case-insensitive on Windows process . env . PORT = " 3000 " console . log ( process . env . port ) // undefined on Linux, "3000" on Windows This one got me during a "works on my machine" incident. My Windows dev box ran fine. The Linux CI server crashed because a teammate typed env.port instead of env.PORT . Your CI runs Linux. Your dev box probably runs macOS or Windows. Case-sensitivity differences will bite you. How to handle it : Use a validation layer that throws on missing keys. A simple getEnv("PORT") will catch typos at startup. 2. Values are always strings console . log ( typeof process . env . PORT ) // "string" even if you set PORT=3000 Number(process.env.PORT) can return NaN without throwing. Boolean values like "false" are truthy strings. How to handle it : Always parse. If you use a schema library like CtroEnv, it coerces types and throws on invalid input. 3. process.env is NOT the same as .env This confused me for way too long. process.env is whatever the shell gave the process. A .env file is just a text file dotenv reads to populate process.env . Node doesn't touch .env files on its own. // This won't read .env automatically console . log ( process . env . MY_VAR ) // undefined How to handle it : Call dotenv.config() at entry, or use @ctroenv/node which loads .env files automatically. 4. You can set env vars per-command PORT = 4000 node app.js This sets PORT only for that single process. It doesn't pollute your shell session. Super useful for one-off runs or testing different configurations without editing files. console . log ( process . env . PORT ) // "4000" 5. process.env is mutable at runtime process . env . DATABASE_URL = " postgres://hacker:gotme@evil.com/db " I've seen code that modifies process.env to "fix" config at runtime. Don't do this. If something i

The first text message ever sent was not a love note, a meeting reminder, or a meme. It was a Christmas greeting. On December 3, 1992, a 22-year-old engineer named Neil Papworth sat at a desktop computer, typed two words, and sent the world's first SMS to a mobile phone: "Merry Christmas." More than thirty years later, that humble two-word message has grown into one of the most quietly important protocols in connected technology, and it still shows up in the IoT devices we build today. The engineer who sent the first SMS Neil Papworth was working for the Anglo-French firm Sema Group Telecoms, part of a team building a Short Message Service Centre (SMSC) for the British carrier Vodafone. The SMSC was the piece of infrastructure that would store and forward text messages across the cellular network. To prove it worked, Papworth sent a test message from a computer terminal to the Orbitel 901 handset of Richard Jarvis, a Vodafone director who was at a company Christmas party. The message arrived. Jarvis read it. But he could not reply, because mobile phones at the time had no way to compose a text. There was no keypad-driven messaging app, no T9, no touchscreen. SMS started life as a one-way novelty riding on a spare slice of the network's signalling channel, and almost nobody involved thought it would matter very much. Why SMS was designed the way it was The technical detail that makes this story relevant to anyone building connected hardware is how SMS was engineered. Text messages were squeezed into the control channel that phones already used to talk to cell towers, the same channel that handles things like call setup. That is why a single SMS is capped at 160 characters: it had to fit inside a small, fixed-size signalling packet. This constraint turned out to be a feature. SMS is lightweight, store-and-forward, and works even when a data connection is weak or absent. The message waits in the SMSC until the device is reachable, then gets delivered. No persistent con

Built a small tool for Claude Code that tracks whether “agent memory” rules actually pay for themselves in token usage. The idea is simple: every persistent instruction should justify itself by reducing future token cost. If it doesn’t, it gets flagged for removal. Over time, a surprising amount of memory ends up being neutral or negative ROI once measured. Check it out, would mean a lot :) Repo: https://github.com/vukkt/token-warden

An AI agent that can email but can't hold a calendar slot is only half useful. The moment a conversation turns into "let's meet Thursday at 2," the agent needs a real calendar — one that sends invitations people accept in Google Calendar or Outlook, receives invites at its own address, and RSVPs back so the organizer sees a real response next to everyone else's. Bolting a scheduling library onto a shared mailbox doesn't get you there; the agent needs a calendar identity of its own. An Agent Account ships with exactly that. Every account gets a primary calendar that hosts events, accepts invitations over standard iCalendar, and RSVPs with yes, no, or maybe. To a participant, the agent is just another attendee on the invite. This post walks through using that calendar from two angles: the HTTP API for your backend, and the Nylas CLI for the terminal. I work on the CLI, so the terminal commands below are the ones I reach for. The calendar an Agent Account comes with When Nylas provisions an Agent Account, it creates a primary calendar that belongs to the account. You reach it through the same Calendars and Events endpoints at /v3/grants/{grant_id}/... that any other grant uses, so calendar code you've written for a connected Google or Microsoft account works here unchanged. Each account gets: A primary calendar , provisioned automatically. It can't be deleted while other calendars exist on the account. Additional calendars , up to your plan's cap, for separating concerns — a sales-calls calendar and an internal one on the same agent. Free/busy queries , so the agent can check its own availability before proposing a time. Event webhooks — event.created , event.updated , and event.deleted fire on every change, whether it came from the agent or from someone responding to an invitation. List the calendars from the terminal with nylas calendar list , or over the API with GET /v3/grants/{grant_id}/calendars . Both return the primary calendar plus any you've added. List what'

An AI agent sends an email, a reply lands three hours later, and the agent has to answer two questions before it can do anything useful: which conversation is this, and what did I last say? Get the first one wrong and the agent's reply shows up in the recipient's inbox as a brand-new message instead of slotting into the existing thread. To the person on the other end, that looks broken — like the agent forgot the conversation it started. Threading is the part of agent email that's easy to get almost right and quietly wrong. The fix lives in a few email headers most developers never touch, and in the Threads API that groups messages into conversations for you. This post walks through both, from two angles: the HTTP API for your backend, and the Nylas CLI for the terminal. I work on the CLI, so the terminal commands below are the ones I reach for when I'm testing a reply loop. The three headers that make threading work Threading runs on three email headers, not on subject lines. Every message carries a Message-ID — a globally unique identifier the sending server stamps on it. When someone replies, their mail client adds In-Reply-To (the Message-ID of the message being answered) and References (the full chain of Message-ID values, oldest to newest). Those two headers are how every mail client decides which messages belong together. Here's what the chain looks like across one exchange. The agent's first message gets a Message-ID ; the reply points back at it; the agent's follow-up references both: # The agent's outbound message Message-ID : <abc123@agents.yourcompany.com> Subject : Following up on your demo request # The recipient's reply Message-ID: <def456@gmail.com> In-Reply-To: <abc123@agents.yourcompany.com> References: <abc123@agents.yourcompany.com> Subject: Re: Following up on your demo request # The agent's follow-up Message-ID: <ghi789@agents.yourcompany.com> In-Reply-To: <def456@gmail.com> References: <abc123@agents.yourcompany.com> <def456@gmail.com> The Ref

Most "AI agent that emails for you" demos point a language model at a human's Gmail inbox over OAuth. That works until the agent needs its own identity: an address people reply to, a calendar that accepts invites, a mailbox your application owns end to end. Borrowing a human's inbox means inheriting their OAuth scopes, their rate limits, and the awkwardness of an agent sending mail as a person who didn't write it. A Nylas Agent Account flips that around. It's a real name@yourcompany.com mailbox that you create and control entirely through the API — it sends, receives, hosts calendar events, and RSVPs, and it's indistinguishable from a human-operated account to anyone on the other end. Under the hood it's just a grant , so the grant_id you get back works with the same grant-scoped endpoints — Messages, Threads, Folders, Drafts, Attachments, Contacts, Calendars, and Events — you've already used for connected accounts, plus the standard webhook triggers. This post is a working tour of provisioning one, from two angles: the HTTP API for your backend, and the Nylas CLI for the terminal and quick experiments. I work on the CLI, so the terminal commands below are the exact ones I reach for. Why an Agent Account beats borrowing a human inbox An Agent Account is a first-class sender, not a delegated one. When the agent owns support@yourcompany.com , people reply to it directly, calendars invite it as a normal participant, and its mail authenticates as coming from you. A few concrete differences from pointing an agent at someone's existing mailbox: No OAuth flow to babysit. Creation needs only an email address on a domain you've registered — there's no refresh token to store or rotate, and the grant rarely expires because there's no OAuth token to refresh. Its own reputation. The account sends on your domain, and a new domain establishes its sender reputation over roughly four weeks of gradual sending. That reputation is yours to protect, not a shared corporate inbox's. Per-t

Developers inheriting sprawling SQL codebases or revisiting queries from weeks earlier know the frustration: a dense, unformatted block that obscures joins, filters, and logical flow. Readable SQL isn’t cosmetic — it directly affects debugging speed, peer review accuracy, and long-term maintainability. What it is SQL Formatter restructures raw SQL into clear, conventionally formatted code, running entirely in the browser. It applies consistent indentation, capitalisation of keywords, and logical line breaks — all without altering the query’s semantics. The formatter understands the syntax of all major database engines, including PostgreSQL, MySQL, SQL Server, and Oracle, so it preserves dialect-specific functions and operators rather than flattening them into a generic style. The tool is one of 200+ free browser utilities on DevTools. It processes all input entirely on your machine — no data ever leaves the browser, no account is required, and no analytics track your usage. That privacy-first design means you can safely format queries that contain proprietary business logic embedded in production SQL. The engine handles the full spectrum of SQL complexity: basic SELECT statements, multi-table joins, Common Table Expressions (CTEs), correlated subqueries, window functions, and DML operations like INSERT or UPDATE . Because it parses the input rather than applying regular expressions, deeply nested constructs retain their hierarchy, with each subquery or CTE level indented to show ownership. How to use it Paste any SQL fragment into the left-hand editor and the formatted result appears instantly in the output panel. A live preview updates as you switch formatting options, so you can tune the output without re-pasting. The primary configuration controls help you match your team’s conventions or personal preference: Dialect : selecting a specific database ensures that functions such as PostgreSQL’s STRING_AGG or MySQL’s GROUP_CONCAT are not inadvertently mangled, and th

As developers, we've all been there. Q: Need to decode a Base64 string? Open one website. Q: Need to convert an image to Base64? Open another website. Q: Need to validate a Base64 string? Search Google again. Q: Need to compare two Base64 values? Yet another tool. I found myself repeatedly switching between different websites, browser tabs, and terminal commands just to perform simple Base64-related tasks. So I decided to build something that solved this problem for me. The Goal Keep every commonly used Base64 utility in one place and make it work directly in the browser. No installations. No command-line knowledge required. No account creation. Just open the website and use the tool What You'll Find Instead of only providing an encoder and decoder, I wanted to cover the complete Base64 workflow. Some of the available tools include: Base64 Encode / Decode Image to Base64 Audio to Base64 Video to Base64 Base64 Validator Base64 Detector Base64 Compare Base64 Repair Base64 URL Encode Base64 File Decoder CSS Data URI Converter And more are being added regularly. Why I Built It Honestly, this started as a personal productivity project. I was using different Base64 tools almost every week and got tired of bookmarking multiple websites for related tasks. Having everything in one place turned out to be surprisingly useful, so I decided to make it public. Give It a Try https://base64converters.com I'm continuously improving it and would love feedback from fellow developers. Are there any Base64-related tools or workflows you use frequently that should be included?

No fancy infrastructure. Just a 50-line Python function that picks the right model for the right query. Last month my LLM API bill hit $340. This month: $67. Same traffic. Same product. The only change was adding a simple router that stops sending every request to Claude Sonnet when GPT-4o mini can handle it just as well. Here's exactly how it works. The Problem When you prototype, you pick one model and hardcode it everywhere. Usually something capable like GPT-4o or Claude Sonnet, because you want good results fast. Then you ship, traffic grows, and you get a bill that makes you question your life choices. The thing is — not all queries need a flagship model. In a typical RAG app: "What is the return policy?" → GPT-4o mini handles this fine "Summarize these 5 conflicting documents and identify the key disagreement" → needs Sonnet You're paying Sonnet prices for return policy questions. That's the bug. The Fix: A Complexity Router import anthropic from openai import OpenAI openai_client = OpenAI() anthropic_client = anthropic.Anthropic() def classify_complexity(query: str) -> str: """Returns 'simple' or 'complex'.""" simple_indicators = [ len(query.split()) < 15, query.endswith("?") and query.count("?") == 1, not any(w in query.lower() for w in [ "compare", "analyze", "summarize", "explain why", "difference between", "pros and cons", "evaluate" ]) ] return "simple" if sum(simple_indicators) >= 2 else "complex" def route(query: str, context: str = "") -> str: complexity = classify_complexity(query) if complexity == "simple": # $0.15/M input — GPT-4o mini response = openai_client.chat.completions.create( model="gpt-4o-mini", messages=[ {"role": "system", "content": context}, {"role": "user", "content": query} ] ) return response.choices[0].message.content else: # $3.00/M input — Claude Sonnet (only when needed) response = anthropic_client.messages.create( model="claude-sonnet-4-6", max_tokens=1024, system=context, messages=[{"role": "user", "content": query}] ) retur

React Server Components in 2026: Patterns, Pitfalls, and When to Actually Use Them Most React Server Components problems stem from teams treating them like regular components with a new rendering location. The architecture shift is deeper than that. RSC fundamentally changes where code executes, what data can cross boundaries, and how developers reason about state. Teams that ignore these constraints burn weeks debugging serialization errors and performance regressions. The pattern that production teams overlook is the server/client boundary itself. Understanding where computation happens, what props can serialize, and when to break out of server rendering determines whether RSC improves or destroys your application's performance. Core Concepts: How RSC Actually Works Under the Hood React Server Components execute on the server and send rendered output to the client. No JavaScript bundle ships for these components. The client receives a serialized tree describing what to render, along with holes for client components to fill. The execution model works like this: the server runs your component tree, fetches data directly, and serializes the result. When the payload reaches the browser, React reconstructs the UI without hydrating server component code. Only client components hydrate with their JavaScript bundles. RSC execution flow from server to client This distinction is critical. Server components cannot use hooks like useState or useEffect because they don't exist in the browser. They render once on the server per request. Client components ship JavaScript and can use the full React API. The implication here is that your component tree becomes a mix of server and client code. The boundary between them determines your bundle size, waterfall depth, and debugging complexity. Production-Ready Patterns: Streaming, Suspense, and Data Fetching The correct pattern for data fetching in server components eliminates the request waterfall. Fetch data directly in the component

The Problem: Feature Velocity Was Creating Structural Debt The system originally started as a simple feature delivery backend: A Django API powering agricultural insights Celery workers handling asynchronous processing Independent endpoints for each new capability A growing set of Earth Observation computations (NDVI, NDWI, etc.) At first, it worked. But as more features were added, a pattern emerged: Each feature introduced its own pipeline logic Observability was inconsistent across services API contracts drifted between frontend and backend Debugging required tracing multiple disconnected systems We weren’t scaling functionality. We were scaling fragmentation. The Turning Point: Features vs Platforms The key realization was simple: Features solve user problems. Platforms solve system problems. We were repeatedly rebuilding: Authentication flows Data ingestion logic Processing pipelines API validation layers Monitoring hooks Each feature was solving its own version of these concerns. That is where platform engineering became necessary. The Shift: Introducing a Platform Layer We introduced a platform layer between feature delivery and infrastructure. Instead of building isolated pipelines, we standardized: 1. Unified API Surface All Earth Observation workflows (NDVI, NDWI, and future indices) were normalized into a consistent API contract. Shared request/response structure Versioned endpoints Schema validation through serializers Central routing logic This eliminated endpoint fragmentation. 2. Standardized Processing Pipeline Celery tasks were refactored into a reusable pipeline pattern: Ingestion Validation Computation Storage Publishing Instead of feature-specific workers, we moved toward composable tasks. This allowed new indices or processing logic to plug into the same execution flow. 3. Observability as a First-Class Layer One of the biggest failures in the original system was visibility. We introduced: Structured logging across all services Traceable job IDs

Treating docs as a product When documentation lives as an afterthought, it shows. Pages drift out of date, examples break quietly, and release notes scatter across a dozen places no one can find. The fix is not a weekend cleanup. It is a decision to treat docs the way you treat any product people depend on: someone owns it, it has standards, and it gets maintained on purpose. That is the decision I made when the docs came to the Developer Relations team at the end of 2025. Not "let's tidy this up," but "this is ours now, and we are accountable for whether a developer can actually build from it." The work, in the repository The honest record of what a team does to a codebase lives in its git history, so that is where the story starts. Comparing the six months before the handoff to the six months since: Before vs. Under DevRel: Commits: 476 → 1,900+ Merged pull requests: 145 → 447 Unique contributors: 21 → 64 A repository that averaged fewer than 500 commits over half a year is now past 1,900 in the same span. The contributor count tripled, because we treated the docs as something the whole community could improve, not a walled garden. This is what a team that decided to do the work looks like when you measure it. Our proudest metric is what was cut In six months, we added roughly 339,000 lines and removed roughly 281,000. That near balance is the point. A neglected docs site accumulates: dead pages, stale tutorials, examples that no longer compile, three slightly different explanations of the same concept. Adding more on top of that does not help anyone. So we cut nearly as much as we wrote. We rebuilt the Hello World walkthrough from 1,300 lines down to about 300 without losing a thing. We consolidated scattered release notes into a single clean reference. A docs site is judged by what a developer can find and trust, not by how much sits on the shelf. A library you can learn from At the start of the year, the examples library had effectively one usable entry. Today,

Alina Krasavina explains how Delivery Hero successfully deprecated Google Analytics and migrated to an internal user tracking platform. She discusses how a simplistic, highly scalable architecture allowed them to handle 10 times more load while capturing 97% of tracking data. By Alina Krasavina

Before I released my own AI chatbot plugin, I ran it through a security review. It came back with 35...

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What is a Link? Definition A link is an interactive element that redirects the user to a new location which can be another section inside the current page, modifying the URL with a # parameter, or a new page. It can be used to download a file. Once activated, it takes the user to the URL set in its href. The browser records that navigation in its history, so the user can return to the previous page using the back button. Semantic The elements needs the attribute href with a valid URL or an IDREF pointing to a section inside the current page to have the semantic value of a link, otherwise it will be considered as generic . <a href= "/URL" > Go to main page </a> Keyboard Interaction It can only be activated by pressing the key Enter . If the key Space is pressed while the focus is on the link, the page will scroll down. Screen Reader Interaction Screen Readers, generally, announce the links in the following way: Link, [accessible name of the link] . It is extremely important to provide a descriptive and correct accessible name to the element. Bad Practice It is completely unnaceptable, a bad practice and goes against the native behavior of the element, forcing it to behave as a button by doing the following: <a href= "javascript:void(0)" onclick= "openModal()" > Open Menu </a> <a href= "#" role= "button" onclick= "button()" > Link with role button </a> If you need to do this, it means that you need a link. What is a button? Definition A button is an interactive element that dispatches an action inside the page where it is located. It does not redirect the user to another place or location nor modifies the url. The actions that are being dispatched can be: open a modal, play a video, post a comment, etc. Semantic The button needs the attribute type with a value according to its action: - type="button" : it is used when the button does not have a default behavior. - type="submit" : it is used when the button sends information to a server. - type="reset" : it is used to

Everyone is asking whether AI can write code. That question is already answered. The more important question is: Can AI understand the system it is changing? The biggest limitation of AI coding tools isn't code generation. It's system understanding. That is no longer the interesting question. AI can already generate APIs, tests, database migrations, infrastructure files, and entire services. The better question is: Does your AI understand the system it is changing? For most engineering teams, the answer is no. And that is where many AI-assisted workflows quietly fail. The illusion of understanding Ask an AI assistant to: create a new endpoint add a background worker generate a service layer write a migration Most models will produce something that looks correct. The code compiles. The tests may even pass. But production systems are not collections of files. They are collections of relationships. The real questions are: Which service owns this capability? Which projects depend on it? Which runtime executes it? Which release gates are affected? Which verification steps must pass? What breaks if this change is wrong? These questions are rarely visible in source code. They exist in architecture, operational knowledge, deployment rules, contracts, and team conventions. That is why an AI agent can generate valid code and still make the wrong change. Bigger context windows won't solve this The common response is: Give the model more context. But more context is not the same as better context. A million tokens of source code still do not explicitly answer: What projects exist? Which commands are safe? What evidence is trusted? What is currently blocked? What is ready for release? The issue is not missing tokens. The issue is missing structure. The missing layer Most AI tools understand: files functions repositories Production systems require understanding: ownership architecture dependencies operational boundaries verification requirements change impact This is the gap betw