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One hundred dollars will buy you 8 pounds of glitter; 10 Domino's pizzas; 406 miniature disco balls from Temu; or 100 cans of Coors Light. For a friend's birthday party one year, Ayla D'Silva spent $100 on sour candy and made a "sour candy salad." Even sweeter was that she didn't have to foot the […]

ASP.NET Core: Building High-Performance Web Applications and APIs A practical guide to ASP.NET Core — the cross-platform framework for building REST APIs, MVC applications, and backend services on .NET, covering architecture, minimal APIs, middleware, performance, and modern patterns. Table of Contents Introduction Architecture Overview Minimal APIs MVC and Controllers Middleware Pipeline Dependency Injection Configuration and Options Authentication and Authorization Performance Features Testing and Observability Quick Reference Table Conclusion Introduction ASP.NET Core is a free, open-source, cross-platform framework for building web apps, APIs, and backend services. It's a ground-up rewrite of the original ASP.NET, designed around three priorities: Performance — it's consistently one of the fastest mainstream web frameworks in independent benchmarks (e.g., TechEmpower). Modularity — you opt into only the middleware and services your app actually needs, instead of a fixed, heavyweight pipeline. Cross-platform — runs identically on Windows, Linux, and macOS, and deploys to containers, serverless, or bare metal. This guide covers the core building blocks you'll use in almost any ASP.NET Core project, from a five-line minimal API to a full MVC application with authentication and background services. 1. Architecture Overview Every ASP.NET Core app starts from a unified entry point — Program.cs — using the minimal hosting model introduced in .NET 6. var builder = WebApplication . CreateBuilder ( args ); // Register services (dependency injection container) builder . Services . AddControllers (); builder . Services . AddEndpointsApiExplorer (); builder . Services . AddSwaggerGen (); var app = builder . Build (); // Configure the HTTP request pipeline (middleware) if ( app . Environment . IsDevelopment ()) { app . UseSwagger (); app . UseSwaggerUI (); } app . UseHttpsRedirection (); app . UseAuthorization (); app . MapControllers (); app . Run (); Two phases matter here:

Distributed backups, cyber resilience, and a half-million records are preserving Palestinian history beyond any single building or border.

I fine-tuned Gemma 4 E2B. The adapter merged cleanly. The export to .litertlm completed without errors. I pushed the model to my phone, initialized the engine, and everything looked green. Then I tried to create a conversation and got this: Failed to apply template: unknown method: map has no method named get (in template:238) No model loading failure. No quantization error. The model initialized, the tokenizer loaded, and then the runtime choked on a Jinja template feature it does not support. This failure only surfaces when you actually try to run inference, not when you load the model. If you are demoing at a hackathon, this is the worst possible time to discover a compatibility issue. I hit this exact bug while building Redacto, a zero-trust PII redaction app that runs Gemma 4 E2B entirely on-device. This post walks through the full fine-tune-to-deploy pipeline: how to QLoRA a model on Colab, export it for LiteRT-LM, and avoid the undocumented template trap that will block your deployment. The Full Pipeline Here is what the fine-tune-to-deploy pipeline looks like end to end: HuggingFace base weights -> QLoRA fine-tune (Colab) -> Merge adapter into base -> Patch chat template <-- the step nobody tells you about -> Quantize + export to .litertlm -> Push to device Each stage has its own failure modes. The template patch step is the one that was undocumented at the time, and it is the one that will cost you hours if you do not know it exists. A note on framing before we dig in: this was an under-resourced fine-tune. I trained on 3,000 of the 400,000 samples in the ai4privacy/pii-masking-400k dataset for a single epoch, and the label format did not fully match what Redacto expected downstream. The point of this post is not the fine-tune's accuracy - it is the deployment mechanics I had to work through to get any fine-tuned model onto the device at all. Step 1: QLoRA Fine-Tuning on Colab QLoRA (Quantized Low-Rank Adaptation) lets you fine-tune a quantized model by tra

🎲 A Tale of Inference Woes 🎲 Thy context window overflows with dread, Thy API keys scattered 'cross thy thread. Thou switchest providers mid-conversation, And pray thy tokens find the right foundation. No ward stands guard when tools go rogue, No grimoire saves a session from the fog. Thy agents wander, masterless and blind, Thy prompts untested—leaving truth behind. Thy wallet weeps. Thy latency doth creep. Thy model's fine. Thy infrastructure? Not so deep. Sound familiar? I'm excited to share the public README for Arcanum — a .NET 10, single-binary, Native AOT, local-first AI inference hub that treats your infrastructure with the seriousness of a dungeon master and the organization of a well-kept grimoire. Arcanum is one self-contained native executable. No runtime prerequisite. No "install the framework first." Just arcanum serve and you're running a full inference platform on loopback. What's in the bag of holding: 🏰 Local-first & encrypted — SQLCipher-encrypted Grimoire persists every session, entry, and memory. Your data never leaves your machine unless you tell it to. ⚔️ Multi-provider native engine — Any OpenAI-compatible API (DeepSeek, Groq, Ollama via /v1, LM Studio, etc.) plus local GGUF models via a managed llama-server lifecycle. One hub, zero vendor lock-in. 🔮 OpenAI API compatible — POST /v1/chat/completions and GET /v1/models work with existing OpenAI clients out of the box. Drop-in replacement for your local stack. 🛡️ Wards & Sanctum — High-risk tools require operator approval before execution. Per-campaign sandboxes enforce path containment, network policy, and OS-level CPU/memory/FD limits via cgroups v2 and setrlimit. 📜 Spells, not prompts — Versioned markdown workflows with dependency resolution, tool allowlisting, and semantic routing. Dry-run cast previews before spending a single token. 🧙 Autonomous Apprentices — Goal-driven agents with plan generation, retry/backoff, autonomous plan revision, DM escalation, and parallel step execution. 🏰 The

"Docker vs Kubernetes" is one of those framings that quietly sends people down the wrong road. It sounds like a choice between two competing tools, so teams treat it like a bake-off. It isn't. Docker builds and runs containers. Kubernetes orchestrates a fleet of them. You can happily use one without the other, and most teams should — at least for a while. The question that actually matters is hiding underneath: do I need an orchestrator yet? That's the one worth thinking about carefully, because the cost of answering "yes" too early is real, and it mostly shows up later, on a Saturday, when you're the one holding the pager. What each tool actually does Let me separate the two cleanly, because the confusion causes most of the bad decisions. Docker (or any OCI-compatible runtime — Podman, containerd, and friends) does two jobs: it builds an image from a Dockerfile , and it runs that image as a container on a host. That's the unit of packaging. When you type this: docker build -t registry.example.com/myapp:1.4.2 . docker run -d -p 8080:8080 registry.example.com/myapp:1.4.2 you've packaged your app and started it on one machine . If that machine dies, your app dies with it. If you need three copies, you start three by hand. If you push a bad image, you roll it back by hand. Kubernetes doesn't build or run containers itself — it schedules them across a set of machines and keeps them in the state you declared. You tell it "I want three replicas of myapp:1.4.2 , behind a stable network name, and if a node dies, reschedule them." Kubernetes then spends its life making reality match that declaration. So they're not competitors. Kubernetes runs your Docker-built images. The real comparison isn't "Docker vs Kubernetes" — it's "a couple of containers on a host I manage" versus "a control plane that manages containers for me." A small, honest comparison Concern Plain Docker (or Compose) Kubernetes Where it runs One host you manage A cluster of nodes If a node dies You notice and

If you're comfortable with docker compose up , you already understand more of Kubernetes than you think. Compose taught you to describe an application declaratively — services, their images, their config, how they talk to each other — instead of running containers by hand. Kubernetes is the same instinct, scaled out across a cluster, with more moving parts because it's solving a harder problem: keeping that application running when machines fail. The good news is the mental model transfers. The honest news is that the operational surface grows, and it's worth knowing exactly what changes before you commit. Let me map the concepts you already know onto their Kubernetes equivalents, show the YAML side by side, and be straight about the parts that get harder. First, the thing that doesn't change: your images This trips people up, so let's clear it early. The Docker images you already build run on Kubernetes unmodified. Kubernetes doesn't use the Docker daemon to run them — most clusters use containerd or CRI-O — but every one of those runtimes runs standard OCI images. That's the whole point of the OCI standard: the image you built with docker build is the same artifact the cluster pulls and runs. docker build -t registry.example.com/myapp:1.4.2 . docker push registry.example.com/myapp:1.4.2 That image works identically whether docker run starts it or a Kubernetes node's containerd does. So the packaging is settled. What changes is everything around the container. The concept map Here's the translation table I'd keep next to you while you learn: Docker Compose Kubernetes What changed service Deployment + Service Running vs. reachable are now two objects image: spec.containers[].image Same OCI image ports: Service (+ Ingress for external) Networking is explicit and named depends_on: probes / initContainers Ordering becomes health, not sequence environment: / .env ConfigMap / Secret Config decoupled from the pod volumes: PersistentVolume / PVC Storage is claimed, not jus

Installing Ubuntu Server 24.04 LTS in an offline mode (no LAN cable or WiFi connected) leaves you with an unmanaged network interface which requires manual configuration post-install. The interface enp4s0 is unmanaged by systemd-networkd and also the service itself is disabled. NOTE: This guide applies to Ubuntu server. On Ubuntu desktop you have the NetworkManager service installed and the steps would be different. To fix the problem follow the steps below: Create a Brand New Netplan Configuration File Look into /etc/netplan . You will probably see the dir is empty. This means the installer completely gave up on configuring the network and didn't create any profiles. Create a new file, e.g. vim /etc/netplan/01-netcfg.yaml . Paste the following configuration network : version : 2 renderer : networkd ethernets : enp4s0 : dhcp4 : true This makes the interface managed by networkd instead of the desktop NetworkManager. Fix permissions The new file needs to be readable only by root so fix it's permissions chmod 600 /etc/netplan/01-netcfg.yaml . Enable network service Enable the network service and make it start on boot: systemctl enable systemd-networkd systemctl start systemd-networkd Run netplan Finally, we need to tell Ubuntu to use our new configuration and activate the network netplan generate netplan apply Network should be up! ip a

Early in building our cloud infrastructure, we had a problem nobody talks about — because it happens so slowly you almost don't notice it. We had eight separate Helm charts. One for services that needed KEDA scaling. One for standard HPA. One for backends that exposed HTTP. One for workers that didn't. One for Azure Functions. One for frontends. Eight charts, all living in the same repository, all drifting apart from each other. The charts started as copies of each other. Over time each one picked up its own fixes, its own conventions, its own slightly-different take on security contexts and ServiceAccount annotations and rolling update strategy. Nobody made a decision to diverge. It just happened. Every time we fixed something in one chart — say, wiring up Azure Workload Identity to every ServiceAccount — we had to remember to propagate that fix to seven others. Sometimes we did. Sometimes we didn't. We'd find out when something broke in an unexpected way six weeks later. Helm chart drift is more dangerous than dependency drift. At least with a dependency, you know what version you're on. With eight loosely related charts, you just don't know what you don't know. This is the story of how we replaced all eight with a single versioned chart, published to an OCI registry, and consumed by 70+ services through ArgoCD multi-source Applications — and what that structure forced us to think clearly about. The Two-Questions Framework The first thing we had to do was figure out why we had eight charts in the first place. What was actually different between services that justified a different chart? We landed on two questions: Does it expose HTTP? — This determines whether it needs an ingress, a Service, liveness/readiness probes on an HTTP path. What drives its scaling? — Standard CPU/memory HPA, or event-driven scaling via KEDA (Azure Service Bus, Event Hubs)? That's it. Everything else — security contexts, Workload Identity, pod anti-affinity, rolling update strategy, how s

While setting up a self-managed Kubernetes cluster on Azure VMs, I hit this error when running sudo kubeadm init on a Standard_B1s VM (1 vCPU / 1 GB RAM): [ERROR NumCPU]: the number of available CPUs 1 is less than the required 2 After checking Stack Overflow and the official Kubernetes documentation ("Before you begin"), I confirmed that kubeadm requires at least 2 CPUs to install the control plane. The fix: I stopped the VM and resized it from Standard_B1s to Standard_B2s (2 vCPU / 4 GB RAM) from the Azure portal, then ran kubeadm init again — the preflight checks passed and the control plane initialized successfully. Posting this in case it helps someone hitting the same issue on a low-tier cloud VM. Thanks to the community for the answers that pointed me in the right direction!

Understanding the 550 SPF Check Failed Error The "550 SPF Check Failed" error indicates that a receiving mail server rejected an incoming email. This rejection occurs because the sender's domain failed its Sender Policy Framework (SPF) validation. SPF is an email authentication protocol defined in RFC 7208 . SPF helps prevent email spoofing. It allows domain owners to specify which mail servers are authorized to send email on behalf of their domain. Receiving mail servers perform an SPF check by querying the sender's DNS for an SPF TXT record. If the sending server's IP address is not listed in the domain's SPF record, the SPF check fails. The receiving server then rejects the email based on its configured policy, often resulting in a 550 error. This error protects recipients from unauthorized emails and enhances email security. Initial Diagnosis: Identifying the Root Cause Diagnosing an SPF failure requires examining the bounce message and the domain's DNS records. The bounce message often provides specific details about the SPF failure. Look for phrases like "SPF validation failed," "unauthorized sender," or "IP address not permitted." Common reasons for a 550 SPF Check Failed error include: Missing SPF Record: No SPF TXT record exists for the sending domain. Incorrect SPF Syntax: The SPF record contains errors, making it unreadable or invalid. Incomplete SPF Record: The SPF record does not list all legitimate sending IP addresses or hostnames. DNS Lookup Limit Exceeded: The SPF record requires more than 10 DNS lookups, violating RFC 7208. DMARC Policy Enforcement: A DMARC (Domain-based Message Authentication, Reporting, and Conformance) policy ( RFC 7489 ) with p=reject or p=quarantine is in place, enforcing strict SPF failure handling. To begin diagnosis, use our SPF checker to verify your domain's SPF record and its validity. This tool quickly identifies syntax errors and lookup issues. Step-by-Step Troubleshooting and Resolution Resolving SPF failures involves

Understanding DMARC and the 'p=none' Policy DMARC (Domain-based Message Authentication, Reporting, and Conformance), defined in RFC 7489, is an email authentication protocol. It builds upon SPF (Sender Policy Framework, RFC 7208) and DKIM (DomainKeys Identified Mail, RFC 6376) to provide domain owners with greater control. DMARC instructs recipient mail servers on how to handle emails that fail authentication and provides reporting on these failures. The p=none policy is often adopted as a preliminary step in DMARC implementation. It instructs recipient servers to take no specific action on emails failing DMARC alignment. Its primary function is to enable the collection of aggregate and forensic reports without impacting email deliverability. Many organizations view p=none as a safe, non-disruptive way to begin their DMARC journey. This initial perception, however, overlooks critical security implications. While it offers visibility, p=none provides no actual enforcement against malicious email. The Critical Security Vulnerability of p=none The fundamental flaw of DMARC p=none lies in its complete lack of enforcement. When a DMARC record is set to p=none , recipient mail servers will not block, quarantine, or reject messages that fail DMARC authentication. This includes emails that spoof your domain directly. Threat actors exploit this vulnerability to conduct phishing, business email compromise (BEC), and brand impersonation attacks. They can send emails appearing to originate from your legitimate domain, knowing that p=none offers no protective barrier. The recipient mail server simply delivers the fraudulent message. This policy effectively leaves your domain unprotected against direct domain spoofing. Despite having a DMARC record, your organization remains susceptible to advanced phishing techniques. The security posture of your email ecosystem is compromised. The Illusion of Insight: Data Without Action DMARC p=none does provide valuable data through its repor

Introduction to DMARC and the p=quarantine Policy DMARC (Domain-based Message Authentication, Reporting, and Conformance), defined in RFC 7489 , is an email authentication protocol. It builds upon SPF and DKIM to provide domain owners with the ability to protect their domain from unauthorized use. DMARC enables senders to specify how receiving mail servers should handle unauthenticated emails originating from their domain. It also provides a mechanism for receiving servers to report back to the domain owner about authentication results. DMARC policies dictate the action receiving mail servers should take when an email fails DMARC authentication. The three primary policies are: p=none : Monitor mode. Receiving servers take no action on failed messages but send reports. This is the initial deployment phase. p=quarantine : Receiving servers should treat failed messages as suspicious. They are typically placed in the recipient's spam folder or flagged for further review. p=reject : Receiving servers should outright reject messages that fail DMARC authentication. This is the strongest enforcement policy. Implementing p=quarantine is a critical step towards full domain protection. It allows domain owners to mitigate spoofing and phishing attempts without immediately blocking legitimate, but misconfigured, email streams. This policy provides a balance between security enforcement and minimizing potential deliverability disruptions. Prerequisites for DMARC p=quarantine Implementation Before deploying a p=quarantine policy, proper configuration of SPF and DKIM is mandatory. DMARC relies on these underlying authentication mechanisms and their alignment with the sending domain. SPF (Sender Policy Framework) SPF, specified in RFC 7208 , allows domain owners to publish a list of authorized sending IP addresses in their DNS. Receiving mail servers check the SPF record to verify if an incoming email originated from an authorized server. An SPF record is a TXT record at the root of

Bolting an LLM onto your pull requests is a weekend project. Building AI code review that your engineers don't disable within two weeks is the actual problem. The failure mode isn't missing bugs — it's crying wolf. Post twenty nitpicks and three hallucinations on someone's PR and they'll mute the bot forever. This is the pipeline we built on Mattrx to earn — and keep — that trust. Mattrx is our multi-tenant marketing-analytics SaaS: ~95k lines of C#, 11 engineers, and enough pull requests that senior-reviewer time was the bottleneck. We tried the naive thing first — pipe the changed file into a model, post the output — and watched the team stop reading it in nine days . TL;DR Dimension Human-only / naive AI (before) AI review pipeline (after) Coverage selective / whole-file dump every PR, diff-focused First-review latency ~6 hours (wait for a human) ~3 minutes (AI first pass) Context none / a naked file diff + call sites + conventions Reviewers one mega-prompt specialized dimensions, in parallel False positives ~35% (so it gets ignored) ~6% (adversarially verified) Merge control human, or nothing severity gate; human always decides Governance none gateway: audit, cost, secret redaction ~90 PRs/week across 11 engineers; the pipeline reviews 100%. First-pass review latency 6h → 3 min. False-positive rate ~35% → ~6% — the single number that decides whether the bot lives or dies. Escaped defects to production down ~40%; senior-reviewer time down ~30%. ~$0.05 per PR (cheap model for style, frontier only for correctness). The one mental shift: AI code review is not about finding issues — models find plenty. It's about not crying wolf . The product is trust, and trust is a false-positive-rate problem. Verify before you comment; let the AI propose and the human dispose. The naive approach — and why it collapses // BEFORE: dump the whole changed file into one prompt, post whatever comes back. foreach ( var file in pr . ChangedFiles ) { var text = await File . ReadAllTextAsyn

In the AI slop-loaded, algorithm-powered modern reality, trends come and go - and the tech industry is no different. For the last few years, The Verge staff has compiled a selection of things that are IN for summer and OUT for summer - and each time there are some strong feelings. (Here are the last […]

A client wanted to know who was on their site and on which page, the way Tidio's widget showed them — but without paying for a Tidio subscription, on an external WordPress site that doesn't use Firebase. The result: an external tracker hooked to an independent Firebase project, live presence via onDisconnect , persistent history in Firestore with IP geolocation — and a final debugging session where a browser CORS error was masking a server crash caused by an empty string instead of null . The context The client already had a third-party live-chat script installed on their site, and that's where the idea came from: "can we see who's on the site and on which page, without using that service?" Two constraints made the request less trivial than usual: the site hadn't been migrated to my usual stack yet — it was still running on WordPress, on different hosting — and there was no intention of introducing Firebase on the WordPress side. Step 1 — understanding what a live-chat widget actually does Before building anything, it was worth looking at what the already-installed script actually did. The tag pasted into the site was just a small loader: it creates a hidden iframe, loads the widget's real "brain" inside it from the provider's servers, which then connects via websocket to their backend to stream presence, current page and events in real time. The interesting part — "see who's on the site and on which page" — isn't in the public script: it all lives server-side at the provider, behind authentication, a proprietary dashboard and a subscription. There was nothing to "detach" from that service: it's client code tied to someone else's backend by design. But the pattern itself — a script tag hooking into an external backend — is exactly what's needed to build the same feature independently, and it fits well with Firebase, which has a native presence mechanism built for precisely this. Step 2 — live presence with Firebase Realtime Database Firebase Realtime Database has a

House of the Dragon, Adventure Time: Side Quests, and The Man Will Burn are just a few of the TV shows you should be watching right now.

Todo projeto que envolve autenticação via telefone acaba esbarrando no mesmo problema chato: como testar isso de verdade? Você não pode ficar digitando seu próprio número toda vez que roda um fluxo de cadastro. Definitivamente não deveria pedir para os colegas de equipe cederem o deles. E a maioria dos pipelines de CI não tem uma pessoa sentada ali, pronta para ler uma mensagem de texto e digitar o código num formulário. É uma daquelas coisas que parecem pequenas até você estar três sprints dentro de um projeto com 2FA via SMS e perceber que a cobertura de teste desse fluxo inteiro é "testei uma vez, manualmente, antes do almoço". Por Que a Verificação por Telefone É Complicada de Testar A maioria dos fluxos de autenticação de um stack típico é fácil de automatizar. Verificação por e-mail, dá para interceptar com uma caixa de entrada de teste ou um serviço de captura de e-mails. Tokens de sessão, dá para mockar. Redefinição de senha, você controla o loop inteiro. O SMS quebra esse padrão porque o código precisa sair completamente do seu sistema, ser entregue por uma rede de telecomunicação real e voltar antes que o teste possa continuar. Essa ida e volta introduz vários pontos de falha que não têm nada a ver com o seu código: atrasos de operadora, filtros de spam, peculiaridades de entrega por região, limites de taxa. Se você já viu um pipeline de CI falhar numa etapa de verificação por telefone e depois passar numa nova tentativa sem nenhuma mudança de código, é quase sempre por causa disso. O instinto de muitas equipes é pegar um número público gratuito de um dos vários sites de "receber SMS online" para checagens manuais rápidas. Isso funciona bem para uma verificação pontual. Mas desmorona rápido quando você tenta automatizar, porque esses números são compartilhados potencialmente por milhares de outras pessoas usando o mesmo pool. Códigos podem se perder numa caixa de entrada lotada, o próprio número pode já estar bloqueado pela plataforma que você está testand

Seven days of flow. Fixed a peer identity binding issue in py-libp2p, automated my Neovim lockfile merges, and added a massive batch of notes on xv6 and Category Theory. 10 commits and a solid PR in the works. TL;DR I managed to hit a perfect seven-day streak this week, balancing some deep-dive p2p networking work with necessary maintenance on my local environment. The highlight was opening a PR in py-libp2p to tighten up how PeerRecords are handled in the Kademlia DHT. On the side, I spent time automating the annoying parts of my Neovim config and dumping a fresh batch of notes into my knowledge base. 10 commits, 204 lines added, and a much cleaner workflow to show for it. What I Built Neovim Configuration & CI I’m a firm believer that your editor should work for you, not the other way around. My nvim repo saw a lot of action this week—9 commits in total—but most of it was under-the-hood maintenance. I’ve been leaning on Lua to keep things snappy, and this week was about ensuring my plugin ecosystem doesn't rot. I pushed several updates to keep plugins at their latest versions, but the real "quality of life" improvement was adding a chore to auto-resolve lazy-lock.json merge conflicts. If you’ve ever worked on your Neovim config across multiple machines, you know the headache of the lockfile drifting. I set up a flow to prioritize incoming changes, which saves me from manually triaging JSON diffs every time I pull from dev . It’s a small tweak, but it removes a recurring friction point in my daily flow. I also spent time cleaning up the root of the config, with about 37 additions and 33 deletions—refactoring is a constant process when you live in your terminal. The Knowledge Base I also put some serious time into main-notes . I’m currently going deep on a few different subjects, and I use this repo as my "second brain." I added 167 lines of new material across 13 files, covering a pretty diverse range of topics: xv6 (the re-implementation of Unix V6), Category Theo

New York City’s Summer of Ludd festival is teaching people how to live offline amid the suffocating presence of Big Tech.