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Source generators are often introduced as a way to remove boilerplate. That is useful, but it was not the main architectural reason FUI moved more of its Unity UI pipeline into Roslyn. The harder question begins after binding code has already been generated: does the runtime still need to scan assemblies, inspect attributes, resolve types, and reconstruct the relationship between a View, ViewModel, BindingContext, and Presenter? FUI's answer is to move that composition step to compile time. The generator does not stop at property notifications and binding callbacks. It also emits binding factories and strongly typed routes, so the Player runtime executes an already-validated object graph instead of rediscovering it. This article explains why that distinction matters, how the design evolved, and what the final architecture gains beyond the vague promise of “less reflection.” The original problem was repetitive protocol code Consider a settings screen with a title, a volume slider, a vibration toggle, and a close button. The ViewModel is small, but connecting it to the UI requires a surprisingly large protocol: propagate property changes to UI elements; propagate control changes back to the ViewModel; connect UI events to commands; perform initial synchronization; unsubscribe every handler during unbinding; construct the matching BindingContext and Presenter. None of these steps is individually difficult. The risk comes from repetition. A missing unsubscribe, an incompatible target member, or an incorrect string may remain invisible until that specific screen opens. The earliest code-generation experiment preserved in FUI's repository was an external FUICompiler executable. It targeted .NET 6, was published as a self-contained win-x64 tool, walked Roslyn syntax nodes, extracted binding attributes, and emitted BindingContext source. The central idea was already present: var classDeclarations = root . DescendantNodes () . OfType < ClassDeclarationSyntax >(); foreach ( v

Understanding when to use <ins> , <del> and <s> HTML tags Comparative Feature <ins> element <del> element <s> element Semantic Definition Represents the content that has been added to a document. Represents a range of text that has been deleted from a document. Represents content that is no longer accurate, correct, or relevant. Use Case New edits in a code, in a text, tracked changes Document edits, tracked changes, or visual/structural revisions (often paired with <ins> ). Outdated information, deprecation notices, old prices, or sold-out items. Accessible Code Pattern The meeting is on <span class="sr-only">previous date: </span><del>Monday</del> <span class="sr-only">new date: </span><ins>Wednesday</ins>. The meeting is on <span class="sr-only">previous date: </span><del>Monday</del> <span class="sr-only">new date: </span><ins>Wednesday</ins>. <span class="sr-only">Original price: </span><s>$100.00</s> Visible Representation The meeting is on Monday Wednesday The meeting is on Monday Wednesday $100.00 $34.99 Unique Attributes cite (URL pointing to the explanation of the deletion) datetime (date/time of the deletion) cite (URL pointing to the explanation of the deletion) datetime (date/time of the deletion) None Default Browser Style By default, it has an underline but it can be changed to a bold style, put a background green to show insertion, etc. Renders with a visual line-through (strikethrough) Renders with a visual line-through (strikethrough) Implicit ARIA Mapping: role="deletion" and role="insertion" The <del> and <s> tags map to the accessibility role of deletion (and <ins> to insertion ). Sighted users see these as struck through or underlined, but screen reader support for announcing these changes is inconsistent. Understanding the Accessibility Tree Mapping Under the W3C Accessibility API Mappings, these tags are programmatically mapped to specific accessibility roles that browsers expose to the OS accessibility tree: <del> maps to role="deletion" (se

The Challenge: Realtime in the Age of Server Components The paradigm shift toward React Server Components (RSC) and the Next.js App Router has fundamentally changed how we architect web applications. We are now defaulting to server-side rendering, which is fantastic for performance, SEO, and initial load times. However, a common friction point arises when we need to inject high-frequency, bidirectional realtime data into these server-rendered pages. Too often, developers fall into the trap of importing heavy socket libraries directly into their server components or wrapping their entire application in massive context providers, effectively bloating the client bundle and negating the performance gains of the App Router. The Solution: The "Client Island" Pattern Instead of fighting the architecture, we can embrace "Client Islands"—a pattern where we isolate the stateful, client-side logic into a tiny, focused leaf component. By keeping the WebSocket management strictly client-side, we ensure that our server-rendered pages remain lightweight, fast, and cacheable. Implementing the WebSocket Island The goal is to keep the WebSocket connection lifecycle outside of the rendering flow. We utilize useEffect to manage the connection, ensuring it only runs on the client, and we tap into data fetching libraries like TanStack Query or SWR to surgically update the UI. ' use client ' ; import { useEffect } from ' react ' ; import { useQueryClient } from ' @tanstack/react-query ' ; export function RealtimeSync ({ token }) { const queryClient = useQueryClient (); useEffect (() => { const ws = new WebSocket ( `wss://realtime.example.com?token= ${ token } ` ); ws . onmessage = ( event ) => { const data = JSON . parse ( event . data ); queryClient . setQueryData ([ ' items ' ], data ); }; return () => ws . close (); }, [ token , queryClient ]); return null ; // This component renders nothing, just manages the side effect } Persistence via RootLayout To prevent the connection from dropp

I spent last weekend building a JSON toolkit in Rust under one rule: no third-party dependencies . Not "few". None. The [dependencies] table in Cargo.toml is present and empty, and Cargo.lock holds exactly one package — the project itself. No serde , No serde_json , No clap , No itoa , No ryu . That constraint is the premise of the Zero Dependency hackathon , and it is a good premise, because it forces you to find out what the standard library actually promises. Here is the thing I did not expect to find: About 10% of the JSON documents that RFC 8259 says a parser must reject are accepted by Rust's own number parser. Not a subtle 10%. NaN , Infinity , .5 , 5. , +1 and 012 are all invalid JSON, and f64::from_str and i64::from_str take every one of them. If you write a JSON parser the obvious way — scan to the end of the number token, hand the slice to from_str — you ship a parser that is silently non-conformant, with no warning anywhere. I have the number because I counted it against a real corpus before writing the parser. The rest of this post is what that measurement did to the design, and what generalizes to languages that are not Rust. What I built jaq-lite is a hand-rolled RFC 8259 parser, a serializer, and a jq-style query CLI with rustc -style caret diagnostics — 4,670 lines under src/ and 4,432 lines of tests, standard library only. $ echo '{"users":[{"name":"ada","age":36},{"name":"linus","age":54}]}' | jaq-lite '.users[] | .name' "ada" "linus" It supports identity, field access, quoted fields, indexes, iteration, pipes, commas, parentheses, the optional operator ? , and eleven builtins ( length , keys , keys_unsorted , type , to_entries , from_entries , flatten , first , last , reverse , not ). Exit codes follow jq: 2 for a bad flag, 3 for a filter that does not compile, 5 for input that is not JSON, 0 otherwise. The measurement JSONTestSuite is the standard conformance corpus: 318 files in test_parsing/ , named by what a parser is supposed to do with them

A lot of developers pick a lane early — frontend or backend — and stay there. I never did, and building ClientIQ is a good example of why. The problem Freelancers waste a lot of time figuring out where to post their skills. Upwork? Fiverr? Toptal? The right platform depends on their profile, their niche, and their experience — and most people just guess. I wanted to build something that could actually recommend the right platform based on real data, not gut feeling. Why this needed a full-stack developer, not two specialists This is where being a full-stack developer actually mattered: The backend needed a Flask API that could take a freelancer's profile data and run it through a multi-model machine learning workflow to generate a recommendation. The frontend needed a clean React interface where users could input their info and see the recommendation in a way that made sense — not just a raw JSON response. The connection between them — API design, request/response shape, error handling — needed someone who understood both sides well enough to make them work together smoothly, not just "talk" to each other. If I had only known React, I'd have needed someone else to build and explain the ML backend to me. If I had only known Flask, the interface would have been an afterthought. Being full-stack meant I could design the whole system as one coherent product, not two separate halves duct-taped together. What I actually built A Flask API that serves multi-model ML predictions A React frontend for input and displaying recommendations A clean handoff between the two — the kind of detail that's invisible when done right, and painfully obvious when it's not The bigger lesson Full-stack development isn't about knowing a little bit of everything. It's about being able to see a product end-to-end and make decisions that make sense for the whole thing — not just your favorite part of the stack. That's the mindset I bring to every project, whether it's a web app, a mobile app, or

Disclosure: I work on Tessera, which is one of the tools in the gap I am describing. Ask a fifty-person engineering organisation how they control production access and you will hear the same answer with small variations: a bastion host, SSH keys distributed by configuration management, a shared kubeconfig somewhere, and a spreadsheet or a Notion page that is out of date. Nobody chose that. It is what remains after the alternatives were priced. How the category got shaped Privileged access management grew up serving banks, telcos and governments in the 2000s. Those buyers had specific characteristics: thousands of administrators, regulators with written opinions, dedicated security teams, and procurement processes measured in quarters. Products shaped themselves accordingly. Six-figure entry prices. Deployments measured in months with professional services attached. Feature sets covering every mainframe and network appliance in a bank's estate. Sales motions that start with a discovery call and a mutual NDA. That was a reasonable fit for those buyers. It is a terrible fit for a company with sixty engineers, no dedicated security team, one person who is security-adjacent, and a procurement process that consists of a founder approving a card payment. So the mid-market did what people do when a category prices them out: they built the minimum themselves. A bastion is a bastion because it was free and it was Tuesday. The problem this leaves The bastion answer works, up to a point, and it is worth being specific about where the point is. A bastion controls the door. It does not control the room. Once someone is through, there is no per-command record, no way to reduce their privileges while they are working, and no session replay. And keys still have to be distributed and revoked behind it, which means the original problem is intact — it just has a nicer front entrance. Three things then converge, usually in the same year: The first enterprise customer. Their security que

Disclosure: I work on an access tool (Tessera), mentioned once at the end. Everything before that is about evidence, and applies whatever you use. The most common surprise in a first SOC 2 or ISO 27001 audit is not that a control is missing. It is that a control exists, works, and cannot be evidenced — so it counts as absent. The distinction is worth stating precisely, because it is not obvious until it has cost you something. A control is a thing that is true about your system. Only authorised engineers can reach production. Evidence is an artefact, produced by a system rather than by a person, that demonstrates the control was operating throughout the audit period — not on the day someone checked. Most organisations have decent controls. Most cannot produce evidence, because their controls live in places that do not emit artefacts: a bastion's authorized_keys file, a spreadsheet, a Slack thread where someone approved something, and the collective memory of three engineers. What gets asked for Reconstructed from what people have told me, this is the shape of the questions: "Show me everyone who could access production on 14 March." Not today. A specific date in the past, usually chosen by the auditor. This is the one that catches people, because most systems can tell you the current state and cannot tell you a historical one. authorized_keys has no history. A spreadsheet has whatever history git gives it, if it is in git, which it usually is not. "Show me that this person's access ended when their employment ended." Both timestamps, from two systems, matched. HR has the first. The second is the problem. "Show me the approval for this elevated access." Not that a policy requires approval — the specific approval, for this specific grant, with who approved it and when. "Show me what was done in this session." Increasingly common where production access to customer data is involved. Not "we log commands", but the actual record for a named session. "Show me that these c

Disclosure: I work on Tessera, which is self-hosted. That is the position I am arguing from, and the costs of that position are in the last section. Security questionnaires ask where customer data is processed. Access-control tools tend to get a shallow answer to that question, because people think of them as gatekeepers rather than as data processors. They are both. Here is what a hosted access broker necessarily knows about you. Your infrastructure inventory. Every registered target: hostnames, addresses, cluster endpoints, database names, environment labels. That is a map of your estate, and it is the document an attacker would most like to read before deciding where to spend effort. Your organisational structure. Who has access to what, which teams exist, who approves for whom, who was granted production access at 2am during an incident. Org charts are inferable from access graphs with unpleasant accuracy. Your session content, if recording is on. Every command, every query, every screen of output. That includes whatever your engineers pasted into a terminal, which — be honest about your own estate here — includes secrets sometimes. Timing. When your incidents happen, how long they last, who gets pulled in. That is commercially sensitive on its own. None of that requires the vendor to hold your credentials. It is the metadata, and the metadata is the part that survives every architectural mitigation. Where this shows up GDPR and processor chains. Session recordings contain personal data — identified individuals performing identified actions at identified times. A hosted vendor is a processor, which means a DPA, transfer mechanisms if data leaves the EEA, and a sub-processor list you have to monitor. It also means their sub-processors become your problem, which is a chain you do not control and cannot easily audit. Sector rules. Financial services, healthcare and public sector procurement in most European jurisdictions have specific requirements about where data

Disclosure: I work on Tessera, which is on the buy side of this. I have tried to cost the build side properly, because a comparison where the build option looks stupid is a comparison nobody believes. Every engineering team that has this problem considers building it. That instinct is correct. SSH certificates are a well-understood, well-documented mechanism, everything you need ships with OpenSSH, and the first working version takes a competent engineer about a week. The week is not the cost. Here is what is. The build, honestly The CA itself. You generate a key pair, configure targets with TrustedUserCAKeys , and sign user keys with a short validity. This part genuinely is a week, and it works. Protecting the CA key. This is where the estimate starts moving. The CA private key can now grant access to every host in the fleet. On a laptop it is an incident waiting to happen. So you want it in an HSM or a KMS, which means an integration, which means the signing operation now has an availability dependency, which means a runbook for what happens when that dependency is down. Call it two to four weeks including the operational work. Issuance. Someone has to request a certificate and something has to decide whether to give them one. That means integrating with your identity provider, mapping groups to principals, building a request path, and building an approval path if you want anything time-boxed or justified. This is the real project, and it is measured in months rather than weeks, because it is where the requirements keep arriving. Rollout across the estate. Editing sshd_config on every production host. Technically trivial, organisationally not: change window, sign-off, rollback plan, and the discovery that four hosts are not in configuration management and one of them is important. Audit. Certificates tell you a session was authorised. They do not tell you what happened in it. If your requirement includes per-command history or session replay — and if you have audi

Disclosure: these are decisions from Tessera, which I work on. They are all small enough to copy into your own service, which is why they are worth writing up. Security feature lists are made of nouns: encryption, RBAC, SSO, audit. The things that actually decide whether a system holds up are smaller than that and never make the list. Here are four of ours, with the reasoning, including the case where we made the trade in the direction most people do not. 1. The login rate limit ignores X-Forwarded-For Rate limiting a login endpoint is table stakes. The question is what you count against. The natural implementation reads X-Forwarded-For , because your service is behind a load balancer and the real client address is in that header. Almost every tutorial does it this way. The problem: X-Forwarded-For is a request header. If your service trusts it, an attacker sets a different value on every request and each one gets its own bucket. You have not built a rate limit, you have built a counter that resets on demand, and the dashboards will look perfectly healthy while the endpoint is being brute-forced. We count against the real TCP connection address instead. That is the peer address of the socket, which an attacker cannot forge without actually controlling that address. The cost is real and worth naming. Behind a reverse proxy, every request arrives from the proxy's address, so the limit applies to the proxy as a whole rather than per client. That is a worse experience in some topologies, and people will file bugs about it. We took that trade because a rate limit that can be bypassed by setting a header is not a degraded rate limit, it is the absence of one — and the absence is worse than useless, because it looks like presence. If you do want per-client limits behind a proxy, the answer is an explicit allowlist of trusted proxy addresses whose forwarded headers you accept, not blanket trust of a header. 2. Target addresses are validated to prevent SSRF Our controller is

Disclosure: the numbers below are from Tessera, which I work on. The reasoning applies to any proxy that sits in a session path. Every vendor page in this category says something like "scales to thousands of users". It is a useless number, because a user who is not connected costs nothing. What costs something is a session that is open right now. So here is the arithmetic instead, with the method, so you can check it against whatever you are evaluating. The unit The controller does not know how many engineers you employ and does not care how many targets are registered. It knows how many sessions are open. The planning rule that has held up for us: on a normal working day, 10–20% of a team is connected at once. A 200-person engineering organisation is 20–40 concurrent sessions, not Size for your own observed peak, but if you are estimating from scratch, start there. This matters because the difference between the two numbers is the difference between a 512 MB VM and an argument about whether you need a cluster. Memory A proxied session is mostly buffers. In our case: about 256 KB of copy buffers, plus 6 to 10 goroutines at roughly 8 KB of stack each. Call it 320 KB per session. The base Go process is about 30 MB. So 200 concurrent sessions is 200 × 320 KB ≈ 64 MB of live data, plus 30 MB base, ≈ 94 MB. Except that is not what RSS will show you, and this is the part people get wrong when they size Go services. Go does not hand memory back to the operating system promptly, and at the default GOGC=100 the collector lets the heap grow to roughly twice the live set before collecting. So resident memory settles at about double the arithmetic. Concurrent sessions vCPU Expected resident Provision up to 50 1 ~90 MB 512 MB 50–200 2 ~190 MB 1 GB 200+ 4 ~380 MB 2 GB The gap between the last two columns is headroom for spikes, not a hidden cost. A controller serving 200 sessions really does use a couple of hundred megabytes. Our Helm chart ships requests: 256Mi and limits: 1Gi ,

Disclosure: I work on Tessera, which is one of the proxy-shaped tools. Both shapes are legitimate and I try to be fair to the other one below. Most comparisons of access-control tools start with feature tables. That is the wrong end. The decision that actually determines whether a rollout finishes is the deployment shape, and there are only two. Shape one: agents and certificates You run an internal certificate authority. Hosts are configured to trust it. Users get certificates that expire in a few hours. For Kubernetes, an agent runs inside the cluster and brokers access from there. What this buys you is genuinely good. Expiry does revocation automatically, which removes the human step that fails. The credential on the user's laptop is worthless tomorrow. The model scales well because the CA does not sit in the data path — once the certificate is issued, the user talks to the target directly, so there is no proxy to size and no bandwidth to plan. What it costs is that you have to change production before you get anything. sshd_config gets rewritten across the estate to add TrustedUserCAKeys . An agent gets deployed into every cluster. In some setups the tool's binary is copied onto hosts. None of that is technically hard. It is organisationally hard. You need a change window, sign-off from whoever owns those hosts, and a rollback plan — for a project whose entire benefit is "nothing bad will happen later". That conversation is where access-control rollouts stall, and it stalls most reliably in exactly the organisations that need the tool most: the ones where nobody is quite sure who owns which box. The other cost is that the CA private key becomes the most sensitive object your company owns, and now you operate a CA. Shape two: a proxy The credential stays on a controller. The user authenticates to the controller. The controller opens its own connection to the target, authenticates with the real credential, and relays. The target sees a normal connection from a nor

Every infrastructure post-mortem contains the same paragraph, and it is never the one anyone expected to write. The initial access was not sophisticated. It was a credential that existed, that worked, and that nobody had a reason to look at — because it had been legitimately issued months earlier, for a reason that had since ended. That is standing access. It is not a vulnerability, so no scan finds it. It is not a misconfiguration, so no posture report flags it. It is the residue of a hundred reasonable decisions: a key added for a migration, a database password shared during an outage, a kubeconfig sent to a contractor who did good work and left on good terms. It stays invisible to the risk register because a risk register asks what could go wrong, and standing access is the record of things that already went right. The distribution problem The mechanism is worth being precise about, because it explains why the usual fixes only partly work. Infrastructure access is almost always handed out rather than granted . A key is copied to a host. A kubeconfig is copied to a laptop. A password is copied into a password manager and then, at two in the morning, into a chat window. Once a credential has been copied, the organisation has permanently lost the ability to list its copies. There is no query that returns the answer. Revocation stops being an operation and becomes an investigation — carried out by people, at the exact moment the person who knew where everything was has left. This is why the honest test of an offboarding process is not "did we remove their access". It is: can we show a third party, at any point in the future, that access ended when we say it ended? Most organisations that pass the first test fail the second, and usually find out during an audit or a due-diligence review, which are the two worst moments to find out. Why the obvious fixes fall short Configuration management as the source of truth is a real improvement. It makes access declarative and pu

Nobody chooses .NET. Not as a student, at least. You hear "backend" and the room splits into Spring...

To add the AWS AppConfig Agent Lambda extension to an AWS Lambda function, you can open the documentation, scroll through a table of ARNs, find the one that matches your AWS Region and architecture, copy it, and paste it into your template. However, a few months later, AWS publishes a new version and now your deployment is silently using an older one. There’s a better approach that uses public parameters in AWS Systems Manager Parameter Store (Parameter Store). What are public parameters in Parameter Store? Many AWS services use Parameter Store to publish read-only public parameters with names that start with aws/service/{service-name} . These public parameters contain up-to-date metadata about AWS services. You've probably seen them used for AMI lookups for fetching the latest Amazon Linux AMI ID without hardcoding it. The same mechanism is available for Lambda layer ARNs, ECS-optimized AMIs, and other resources that AWS updates regularly. The key idea is instead of looking up a value in documentation and pasting it into your code, you query Parameter Store at deploy time and get the current value. The only IAM permission that's required is ssm:GetParameter . The parameters are public and readable from any AWS account. The problem with hardcoded layer ARNs The AWS AppConfig Agent Lambda extension is distributed as a Lambda layer. To attach it, you need the layer's ARN, which includes a version number at the end: arn:aws:lambda:us-east-1:027255383542:layer:AWS-AppConfig-Extension:128 That version number changes every time AWS releases an update. If you hardcode it, you get a working deployment, but you also get silent drift. A few months from now, you'll be running an older version without realizing it. Imagine a team that's managing dozens of functions in multiple AWS Regions, and you can see how this can become a maintenance problem. Someone has to regularly check the documentation, update the ARN, and redeploy. It's not difficult work, but it's the kind of thing

Since 2021, our team at Autor has shipped over 50 AI products across healthcare, fintech, logistics, and SaaS. Some of them are running in production right now, handling thousands of automated calls per month. Others failed spectacularly — and those are the ones that taught us the most. Where This Comes From I started Autor in Toronto as a one-person AI development shop. The original thesis was simple: companies needed custom AI but couldn't hire fast enough to build it themselves. Four years and 50+ products later, we're a senior-only studio with a production voice AI platform (Loquent) serving healthcare and dental clients 24/7. Along the way, we've impacted over 5 million users, helped clients raise more than $10 million in funding, and shipped across 10+ countries. This isn't a highlight reel. This is the unvarnished list of things I got wrong, figured out the hard way, or wish someone had told me before I wrote my first line of production AI code. 1. Your First AI Product Should Be Boring Our first few products were ambitious. Multi-modal pipelines, complex reasoning chains, novel architectures. Most of them took twice as long as estimated and required constant babysitting in production. The products that actually made money and kept clients happy? A straightforward document classifier. A simple intent router. A basic FAQ bot with good fallback logic. I used to think "boring" meant "not innovative." Now I know boring means "reliable enough that I don't get paged at 3am." Our most successful product, Loquent, handles healthcare scheduling calls. It's not doing anything architecturally exotic. It picks up the phone, understands what the caller needs, books or reschedules an appointment, and hangs up. The magic isn't in the model — it's in the 200+ edge cases we've handled around it. If you're building your first AI product, pick the most boring version of your idea and ship that. You can add complexity later. You cannot add reliability later. 2. Prompt Engineerin

Originally published on Medium It's 2:51am. The incident is resolved. Error rate is back to zero, the rollback worked, and your on-call pager has finally gone quiet. Now you have to write the postmortem. If you've been in SRE or DevOps for any length of time, you know this feeling. You're exhausted, your brain is running on adrenaline fumes, and somewhere in the back of your mind you know that what you write in the next hour is going to be read by engineers, product managers, and probably a VP or two. It needs to be clear, blameless, specific, and actionable. Most of us write it badly. Not because we're bad at our jobs — because we're human beings who just spent two hours firefighting and now we're staring at a blank document at 3am trying to remember the exact sequence of events. There's a better way. The Problem With How We Write Postmortems The standard postmortem template is a solved problem. Every company has one. Timeline, root cause, contributing factors, action items — we all know the structure. The hard part isn't the structure. It's the writing. Specifically: Reconstructing the timeline from a chaotic Slack thread where half the messages are noise Writing the root cause narrative in plain language when your brain is still in technical mode Generating action items that are actually specific and assignable instead of vague gestures toward improvement Translating all of it into an executive summary that a non-technical VP can understand without losing the technical accuracy Each of these is a hard writing task under normal circumstances. At 2am after an incident they're brutal. What Changed for Me I started treating postmortem writing like any other repetitive engineering task: I built a system for it. Specifically, I built a set of AI prompts designed for the exact scenarios SREs face. Not generic "write me a postmortem" prompts — structured prompts that work with the raw material you actually have in front of you at the end of an incident. The key insight w

Today SparkLLM releases and open-sources two on-device general models: Spark X2.5-4B and Spark X2.5-1.7B . Both natively support a context window of up to 1,000,000 tokens — as far as we know, the only on-device models to do so. Why 1M context on-device In real work, you rarely hand a model a single question — you hand it a whole after-sales manual, a set of meeting materials, a batch of project docs, or an entire code repository. On-device models used to chop long content into pieces and ask about each separately, which loses context and drops information. Spark X2.5-4B and 1.7B natively support up to a 1M-token context window, trained on hundreds-of-billions-of-tokens of high-quality long-document data, so they can take in and reason over far more information in a single task — and keep the full picture across a continuous, multi-step interaction. Not just answering — doing the work Long context decides whether the model can see everything; agent + tool-use decides whether it can act on it. Office (with Loomy): upload a sales spreadsheet and ask for an analysis plus a bilingual department report — X2.5-4B writes a script to aggregate the data, extracts key metrics and trends, generates a ~3,000-word Chinese report, produces an English version in the same structure, and validates content, structure and layout end to end. Code: on algorithm implementation, completion and generation, X2.5-4B rivals cloud models 2–3× its size . It plugs into open harnesses like DeepSeek Harness, OpenCode, Codex and Pi for local dev and automation — with low latency, offline use, and code kept on-device. Smart home: on the Domux smart-home test set, X2.5-1.7B reaches 90.3% end-to-end command accuracy at 0.85s average latency. Robotics: both sizes suit continuous perception-and-execution on-robot or on edge devices — operation control, target tracking, navigation decisions — with less dependence on the cloud. Domestic compute, open deployment Both models were trained end to end on a ful

The Problem: Testing Across Regions Is Hard If you're a developer, you've probably faced...

A raw sold-listings search is not automatically a usable comp set. Search for a phone and you may also get cases, chargers, broken screens, empty boxes, and nearby models. Search for a camera lens and you may get caps, adapters, or a different focal length. If those rows go directly into a median, the result can describe the search noise instead of the product. I wanted a larger measurement than a single convenient example, so I ran a fixed 100-product study through CompSniper, the sold-price API I own. The goal was not to prove that an automated classifier is always correct. The goal was narrower: Measure what the production relevance cleaner removed and how the product-level median changed on one predeclared sample. The protocol I selected the products before making the first request: 20 smartphones and tablets 20 gaming and computing products 20 cameras and lenses 20 audio and music products 20 collectibles and luxury products Every search used the same settings: Marketplace: ebay.com Sold window: 2026-06-02 through 2026-08-31 Page: 1 Requested rows: 240 Sort: ended recently Condition: any Relevance cleaning: enabled Each relevance-enabled response contained the raw sample count and raw median captured before classification, followed by the cleaned rows and deterministic price summary from the same fetched page. That meant one production request per product, not separate raw and cleaned fetches. All 100 requests succeeded with unique request IDs. The headline results Across the study: 19,220 priced raw rows were parsed 11,942 priced rows remained after cleaning 7,278 rows were classified out The weighted removal rate was 37.87% 34 of 100 product medians changed by at least 10% 15 of 100 changed by at least 25% 11 of 100 changed by at least 50% The direction was not always upward: 73 medians increased 21 medians decreased 6 medians stayed unchanged That is important. The cleaner is not instructed to raise prices. It tries to retain listings for the requested produ