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Before Keurig, the coffee in your office was almost certainly terrible. Old, burned, made by someone who would rather poorly eyeball than properly measure. Just altogether gross. After Keurig? You could make your own coffee, a cup at a time, exactly when you needed it. The single-cup brewer was an elegant solution to an extremely […]

The heat of the Hadean may have come from impacts as well as the interior.

We’ve all been there. You have a "Leg Day" scheduled in your Notion database, but you woke up feeling like a truck hit you. Your Apple Watch says your Heart Rate Variability (HRV) is in the gutter, but your rigid calendar doesn't care. Usually, you’d either push through and risk injury or manually move cards around in Notion—which is a friction-filled nightmare. In this tutorial, we are building a Self-Optimizing Health Agent using LangGraph , Notion API , and HealthKit . This agent acts as a closed-loop system: it analyzes your physiological recovery data, reasons about your physical state using an LLM, and automatically rewrites your training schedule. By mastering AI agents , LLM orchestration , and fitness automation , you’ll turn your static "To-Do" list into a dynamic "Should-Do" list. 🥑 The Architecture: The Bio-Feedback Loop Using LangGraph , we can treat our fitness logic as a state machine. Unlike a linear script, a graph allows our agent to decide whether it needs to fetch more context (like yesterday's sleep) before making a final decision on your workout. graph TD Start((Start)) --> FetchHRV[Fetch HRV Data via HealthKit] FetchHRV --> CheckRecovery{LLM: Analyze Recovery} CheckRecovery -- "Low Recovery (Fatigued)" --> ModifyNotion[Action: Downgrade Workout Intensity] CheckRecovery -- "High Recovery (Fresh)" --> KeepNotion[Action: Maintain/Boost Intensity] ModifyNotion --> UpdateNotion[Update Notion Page] KeepNotion --> UpdateNotion UpdateNotion --> End((Done)) style CheckRecovery fill:#f96,stroke:#333,stroke-width:2px style FetchHRV fill:#bbf,stroke:#333 Prerequisites Before we dive into the code, ensure you have: Python 3.10+ LangChain & LangGraph installed ( pip install langgraph langchain_openai ) Notion Integration Token (with access to your workout database) HealthKit SDK (Note: Since we are in a Python environment, we'll simulate the HealthKit fetcher, though in a real-world scenario, this would be bridged via a FastAPI endpoint from an iOS app). St

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

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

Cycle recently introduced a separate EU-based control plane, allowing European customers to keep platform management data and telemetry within Europe. The new offering is designed to improve compliance, operational isolation, and responsiveness for European organizations. By Renato Losio

Walkthrough experience includes visits to stars, exoplanets, and observatories.

The Quest Begins (The "Why") I still remember the first time I faced a problem that asked for the sum of numbers in a sub‑array, over and over again, with updates sprinkled in between. It felt like I was stuck in a never‑ending loop of for i in range(l, r+1): total += arr[i] – O(n) per query, and with up to 10⁵ queries the solution timed out every single time. I was staring at the screen, thinking, “There has to be a smarter way to answer these range questions without scanning the whole array each time.” That moment was my dragon: a seemingly simple problem that kept biting me because I kept reaching for the brute‑force sword. I needed a data structure that could give me the answer in logarithmic time while still supporting point updates. Enter the segment tree – the tool that turned my O(n·q) nightmare into an O((n+q)·log n) victory. The Revelation (The Insight) So why does a segment tree work? Imagine you have an array and you want to know the sum of any interval [l, r] . If you could break that interval into a handful of pre‑computed chunks, you’d only need to add those chunk values together instead of touching every element. A segment tree is exactly that: a binary tree where each node stores the aggregate (sum, min, max, etc.) of a segment of the original array. The root covers the whole array [0, n‑1] . Its two children cover the left half and the right half, and this keeps splitting until the leaves represent single elements. The magic lies in two facts: Every node’s value is a function of its children. If you know the sum of the left child and the sum of the right child, the parent’s sum is just their addition. This means we can build the tree bottom‑up in O(n) time. Any interval can be represented as O(log n) disjoint nodes. When you walk down the tree to answer [l, r] , you either take a whole node (if its segment lies completely inside the query) or you recurse further. Because the tree’s height is log₂n, you’ll visit at most 2·log₂n nodes. Thus, building

For decades, to be a gamer was to accumulate a lot of stuff. Consoles, controllers, accessories, weird VR gloves that never worked properly, but mostly the games themselves. Over the years, games have come in every shape and size you can imagine. And now that era appears to be ending. On this episode of The […]

We’ve got a special Decoder today — I had the chance to talk with Amy Lanzi, the CEO of Digitas North America, in front of a live audience at the Uber Villa at the Cannes Lions advertising festival in the South of France. I know, it’s a hard gig, but I do it for you. […]

A company shifted from project- to product-thinking after their platform outgrew single-team use. The limitations that they felt with their platform were one-off deliveries, lack of product vision, and weak feedback loops. They have moved toward a self-service, API-driven, multi-tenant infrastructure with clearer ownership and better abstractions. By Ben Linders

The actor and investor is joining forces with Morgan Beller, who was previously a GP at NFX, to invest in early-stage startups.

The autonomous vehicle space is starting to feel like a repeat of the 2016 hype cycle. Travis Kalanick is back building a robotics company, and the talent wars and capital are heating up the same way they did the first time around. The money’s flowing back, and it’s the people who lived through that first […]

The panelists explain the realities of running AI systems reliably at scale. While building models is solved, maintaining production databases under constant pressure is not. They discuss the emerging architectural decisions separating teams that scale gracefully from those facing catastrophic outages, and what engineering leaders must rethink today. By Simerus Mahesh, Alex Infanzon, Meryem Arik, Luca Bianchi, Renato Losio

CalcMora just crossed 200 live tools calculators and converters spanning finance, health, math, unit conversions, date/time, everyday life, and sports. It's a small milestone against the bigger target (3,000 tools within a year), but it's the first one that felt like proof the approach actually works. What CalcMora is A free calculator and converter site, built to be fast and genuinely useful rather than bloated with unnecessary interactivity. Every tool lives on its own page, static by default, ad-supported, and designed to actually rank and hold up in search rather than just exist. The stack is intentionally boring: Astro for static output, hosted on Cloudflare Pages . No client-side framework runtime, no heavy JS bundles. That choice is mostly why the site stays fast even as the tool count climbs into the hundreds; static pages don't get slower just because there are more of them. Consistency at scale Going from a handful of tools to 200 forced us to think hard about repeatability. Every tool page follows the same underlying template: a calculator, supporting explanatory content, an FAQ section, and standard trust/attribution elements (author info, last-updated date, disclaimers where relevant). That consistency is what makes it realistic to keep scaling toward thousands of pages without every single one needing a bespoke pass. Structured data (schema.org markup) is baked into every page too; it's a big part of why individual calculators show up well in search, and it's applied consistently rather than as an afterthought. New: embeddable tools The other big addition alongside the 200-tool mark is an embed system — every tool on CalcMora can now be dropped into someone else's site as a lightweight, ad-free widget. Site owners get a copy-paste snippet, no signup required. The implementation leans on a couple of iframe and query-param tricks to keep embedded calculators fast and chrome-free (no header, footer, or ads, just the tool), without needing any JS framework

If your Terraform plans are slow, your blast radius is too wide, or multiple teams are stepping on each other's changes, it's time to split your monolith. See The Problem with Large Terraform States for how to diagnose whether you've reached that point. This guide walks through the process of breaking a monolithic Terraform state into smaller, focused states — and how Snap CD can manage the dependencies between them so you don't have to. The approach 1. Identify natural boundaries Look at your resources and group them by lifecycle and ownership. Common boundaries: Networking — VPCs, subnets, route tables, NAT gateways. Changes rarely, underpins everything. DNS — Zones, records. Usually owned by a platform team. Compute — Kubernetes clusters, VM scale sets, container services. Changes more often, depends on networking. Application infrastructure — Databases, caches, queues, storage accounts. Owned by application teams. Monitoring — Dashboards, alerts, log sinks. Changes frequently, depends on everything but nothing depends on it. A useful test: if two resources would never be changed in the same PR by the same person, they probably belong in different states. 2. Map the dependencies Before you move anything, draw the dependency graph. Which groups produce values that other groups consume? networking dns │ ▲ ▼ │ compute ──────────►─┘ │ ▼ application │ ▼ monitoring The outputs that cross these boundaries are what you'll need to wire up after the split. Typical examples: Networking → Compute: vpc_id , private_subnet_ids Compute → DNS: load_balancer_ip Compute → Application: cluster_endpoint , cluster_ca_certificate Application → Monitoring: database_id , cache_name 3. Use terraform state mv to migrate resources Terraform's state mv command lets you move resources from one state to another without destroying and recreating them. # Initialize the destination state cd modules/networking terraform init # Move resources from the monolith to the new state terraform state mv \

At some point every growing Terraform project hits a wall. Plans that used to finish in seconds now take minutes. Applies feel risky because hundreds of resources share a single blast radius. Colleagues avoid running terraform plan because it hammers cloud APIs hard enough to trigger throttling. The state file itself becomes a liability — large, slow to lock, and one bad write away from corruption. This guide covers the symptoms of an oversized state, the band-aids teams reach for, and the structural fix that actually works. How Terraform state works under the hood Every terraform plan does two things: Refresh — for every resource in state, Terraform calls the provider's API to read the current real-world status. A state with 500 resources means 500+ API calls, often more when resources have nested data sources. Diff — compare the refreshed state against the desired configuration and produce a change set. The refresh phase is the bottleneck. It's sequential per provider (parallelism helps across providers, not within one), and every resource pays the cost whether you changed it or not. Adding ten resources to a 500-resource state doesn't make plans 2% slower — it makes the refresh 2% slower on every single plan, for every engineer, forever. Symptoms of a state that's too large Slow plans The most visible symptom. Plan time scales with resource count because every resource is refreshed on every plan, regardless of whether its configuration changed. The exact speed depends on provider — AWS resources with complex nested structures (IAM policies, security group rules) are slower to refresh than simple ones, and Azure resources that require multiple API calls per refresh are worse still. These aren't edge cases — users regularly report 2,900-resource states taking 20–25 minutes to plan and 1,600-resource states taking 8+ minutes . Even starting Terraform with a large state can take minutes before a single API call is made . There's a long-standing proposal for terraform

Elastic open-sourced Atlas, a system built on Elasticsearch that maintains three categories of memory for agents. Atlas integrates with agents via MCP and maintains per-user isolation of memories. When evaluated on question-answering capability, it scored 0.89 Recall@10. By Anthony Alford

SokoFlow Build Log — Month 1 of 4 Last semester I set out on a new strategic plan to level up my software development skills through deliberate, project-based learning. That work produced one of the most ambitious things I've built so far: Sim-Pesa , a local-first transactional appliance that lets developers working in the M-Pesa ecosystem test and simulate STK Push workflows entirely on their own machines, without depending on the Daraja sandbox. I documented that build in 16 weekly posts, which you can find here . This semester, the focus shifts — from fintech foundations to cloud-native integration and real-world systems. The flagship project is SokoFlow , a conversational ERP for small Kenyan shopkeepers to track inventory and record sales entirely through WhatsApp chat. No app to download, no training session required — just natural language. Where Sim-Pesa lived in a controlled, predictable transactional world, SokoFlow steps into the mess of cloud-native reality: third-party API failures, webhook signature verification, the statelessness of HTTP, and container orchestration. The target audience shifts too — Kenyan SMEs operating on infrastructure that is often unreliable by design, not by exception. It's an ambitious project, but the goal was always to learn as much as possible from it. With the plan in place, I got to work. 1. The Vision of a Headless ERP The first real question I had to answer before writing a line of code: what does "headless" actually mean? Headless architecture decouples the frontend — the "head," or user interface — from the backend, the "body" that holds the data and business logic. A conventional ERP bundles both: backend plus a dashboard or UI on top. A headless ERP, by contrast, is just the engine. The brain. There's no built-in screen. So how do users interact with a system that has no interface of its own? SokoFlow doesn't actually care. It could be: WhatsApp SMS A web app A mobile app A voice assistant In this case, the "frontend

For decades, the senator has argued that concentrated wealth threatened American democracy. Now he’s betting that frustration with Big Tech, billionaires, and unchecked AI is reaching a tipping point.