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Choosing a thread-safe collection is not simply a matter of replacing Dictionary<TKey, TValue> with ConcurrentDictionary<TKey, TValue> . The right choice depends on the operations you need to make atomic, the ratio of reads to writes, whether consumers must block, and whether the data can become immutable after construction. This guide explains how ordinary generic collections fail under concurrent access, then compares the main types in System.Collections.Concurrent with immutable and frozen collections. The goal is to give you enough mechanical detail to defend the choice in code review—not just a catalog of APIs. C# Concurrent Collections: Quick Selection Guide Requirement Start with Concurrent FIFO processing ConcurrentQueue<T> Concurrent LIFO processing ConcurrentStack<T> Concurrent key-based reads and updates ConcurrentDictionary<TKey, TValue> Unordered items produced and consumed by the same workers ConcurrentBag<T> Blocking or bounded producer-consumer flow BlockingCollection<T> Snapshot-style updates System.Collections.Immutable Build-once, read-many lookup data System.Collections.Frozen The table is a starting point, not a substitute for checking which compound operations must be atomic. The sections below explain the mechanics and tradeoffs behind each choice. Why C# Needs Thread-Safe Collections C# 1.0 introduced System.Collections , which includes ArrayList , Hashtable , Stack , Queue , and other collection classes. The problem is that these collections are not type-safe. They store elements as object , which can lead to type-mismatch exceptions and to performance costs from boxing and unboxing. C# 2.0 then introduced the System.Collections.Generic namespace and collection classes such as List<T> , Dictionary<TKey, TValue> , Stack<T> , and Queue<T> . These collections are type-safe, but not thread-safe. Type safety means that when you create a generic collection, you specify the type it stores as a generic type parameter. Reading an element then returns

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

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

OpenAI Usage API api_key_id grouping solves a practical reporting gap: I can see which API key produced completion-token activity and which key accumulated cost. The tricky part is not making the two requests. It is joining their daily buckets without dropping unattributed or unmatched data. I want a reconciliation report to expose gaps, not smooth them over. A missing cost row, a cost-only row, or a null key ID can each be useful evidence. This pattern keeps those cases visible with a deterministic .NET sample that needs no credentials or paid calls. Why OpenAI Usage API api_key_id needs a full-outer join OpenAI's August 4, 2026 API changelog added API-key filtering and grouping to the usage and cost APIs. That gives both responses a shared operational dimension, but it does not make them identical datasets. The completions usage endpoint reports measures such as input tokens, output tokens, and model requests. Its api_key_id can be null. The costs endpoint returns monetary amounts and currency, also with a nullable API-key dimension. An inner join would retain only rows present in both responses. That is attractive for a tidy chart, but unsafe for reconciliation. It can hide a key that has token usage but no matching cost row, a key with cost but no completion row, or an unattributed bucket. I use a full-outer join keyed by (start_time, end_time, api_key_id) instead. Null or blank IDs become an explicit display value such as <unattributed> ; they do not disappear. Query both APIs at the same daily grain The Costs API supports daily buckets, so I request bucket_width=1d from both endpoints. I also group by the same single dimension: GET /v1/organization/usage/completions ?start_time=... &end_time=... &bucket_width=1d &group_by=api_key_id GET /v1/organization/costs ?start_time=... &end_time=... &bucket_width=1d &group_by=api_key_id Both resources paginate with has_more and next_page . I keep requesting pages until has_more is false. If a response says more data exis

Grok 4.6 — SpaceXAI's latest frontier model — just landed in public preview in Microsoft Foundry as an Azure Direct Model. The headline isn't "another big model dropped." It's that Grok 4.6 is built specifically for long-horizon, agentic work: planning across many steps, calling tools reliably, recovering when something goes wrong, and handing you a finished work product instead of a half-baked fragment you have to stitch together yourself. That's a meaningfully different design target than "answer this one prompt well." And it's exactly the kind of thing that matters once you move past demos and start building agents that actually have to survive contact with real workloads. As always: no Python required, no notebook required. Just Microsoft.Extensions.AI and dotnet run . What Grok 4.6 Actually Is A few things worth knowing before you touch any code: Frontier reasoning at value pricing. Grok 4.6 is positioned as the value-tier frontier option — frontier-class reasoning at a materially lower cost per task than comparable models. That matters the moment "reasoning agent" stops being a one-off demo and becomes something running continuously in production. Selectable reasoning effort. You choose reasoning depth per call — low , medium , high , or xhigh (default high ) — instead of paying maximum-reasoning cost on every single request regardless of whether the task needs it. Long-horizon agentic execution. It's designed to sustain complex, multi-step work — planning, tool calls, error recovery, and self-verification — with limited human babysitting. Multimodal input. Text and images, so document-heavy, diagram-heavy, and screenshot-heavy workflows don't need a bolted-on separate vision pipeline. 200K token context window at launch. Solid for most agentic and document-analysis workloads — just set expectations up front if your scenario needs more. Still preview. Validate against your own prompts, tools, and safety thresholds before anything production-sensitive touches i

A modular monolith without enforcement is not an architecture — it is a monolith with good intentions. The Problem Most teams skip the modular monolith and jump straight to microservices. The ones that do attempt a modular monolith rely on convention — "don't cross module boundaries" — which fails the moment deadlines hit. The difference between a well-structured modular monolith and a mess is whether boundaries are maintained by tooling or by convention. The Solution Structure Each module is a pair of .NET projects: src/Modules/ Orders/ YourApp.Orders/ ← internal: domain, application, infrastructure YourApp.Orders.Contracts/ ← public: DTOs, interfaces, events Payments/ YourApp.Payments/ YourApp.Payments.Contracts/ The rule : modules may only reference each other's *.Contracts projects. The compiler enforces this physically — no project reference means no type access. Four Layers of Enforcement Compiler — project references prevent cross-module type access NetArchTest — architecture tests fail the build on namespace-level violations NDepend CQLinq — catches dependency cycles and coupling the compiler can't see Quality Gates — block PRs that introduce new boundary violations Module-Scoped Data Each module owns a dedicated DbContext with a schema prefix ( orders.* , payments.* ). No module queries another module's tables. Cross-Module Communication Modules communicate via MediatR in-process events. Orders publishes OrderPlaced ; Payments subscribes — without Orders knowing Payments exists. This is also the extraction seam: when you eventually extract a module into a service, MediatR becomes a message broker. The event contract stays the same. Parallel CI strategy : matrix : module : [ Orders , Payments , Inventory ] fail-fast : false Each module's tests run in parallel. CI time scales with the slowest module, not the total count. The Extraction Path When a module genuinely needs independence: Add outbox table → publish to real broker Replace MediatR handlers with brok

Leaving a class open to inheritance is a design decision, not a default you can ignore. The core idea An unsealed class is a promise: every virtual member can be overridden without breaking what the class guarantees. Most classes never meant to make that promise. They're just unsealed by default, because that's what class gives you unless you say otherwise. Common mistake: treating sealed as "I don't want to think about subclassing" rather than "this type's invariants would break if someone could." One override breaks the promise Here's the promise, a BankAccount that refuses to go negative: public class BankAccount { public decimal Balance { get ; protected set ; } public virtual void Withdraw ( decimal amount ) { if ( amount > Balance ) throw new InvalidOperationException (); Balance -= amount ; } } And here's the override that breaks it: public class RiskyAccount : BankAccount { public override void Withdraw ( decimal amount ) { Balance -= amount ; // no check } } Nothing here is exotic. It compiles cleanly, and RiskyAccount is a perfectly legal BankAccount as far as the type system is concerned. Open one with a balance of 100 and withdraw 500: BankAccount account = new RiskyAccount ( 100m ); account . Withdraw ( 500m ); Console . WriteLine ( $"Balance: { account . Balance : F2 } " ); Real dotnet run output: Balance: -400.00 The check on the left never ran. virtual was an open invitation, and RiskyAccount took it. Sealing turns a silent bug into a compile error Without sealed , the code above compiles and produces a wrong answer at runtime; nothing points you at the problem until it's already in production. With sealed , the same mistake becomes something the compiler catches before the code ever runs: public sealed class BankAccount { public decimal Balance { get ; protected set ; } public void Withdraw ( decimal amount ) { if ( amount > Balance ) throw new InvalidOperationException (); Balance -= amount ; } } public class RiskyAccount : BankAccount { } // error

Customizing cell backgrounds in Excel is one of the fastest ways to transform a plain data dump into a professional, scannable report. Whether you need to highlight headers, flag key metrics, or add visual polish to dashboards, the Free Spire.XLS for .NET library makes it easy to apply solid fills , texture patterns , and gradient effects programmatically. In this guide, you'll learn how to implement each style with concise C# examples. Prerequisites Install the library via NuGet Package Manager: Install-Package FreeSpire.XLS Then add the required namespaces to your project: using Spire.Xls ; using System.Drawing ; 1. Solid Fill (Flat Background) The solid fill is the most common background type—ideal for headers, totals, or status-based highlighting. using ( Workbook workbook = new Workbook ()) { Worksheet sheet = workbook . Worksheets [ 0 ]; CellRange cell = sheet . Range [ "B2" ]; cell . Text = "Solid Background" ; // Solid fill requires the pattern to be explicitly set to Solid cell . Style . FillPattern = ExcelPatternType . Solid ; cell . Style . Color = Color . LightGreen ; workbook . SaveToFile ( "CellSolidColor.xlsx" , ExcelVersion . Version2016 ); } ⚠️ Crucial : Always set FillPattern to ExcelPatternType.Solid before assigning a color. If omitted, the color change will be ignored. 2. Texture Fill (Pattern Overlay) Texture fills overlay a repeating pattern (e.g., brick, checker, or angle) over a base color. They're perfect for subtly distinguishing data categories without overwhelming the reader. using ( Workbook workbook = new Workbook ()) { Worksheet sheet = workbook . Worksheets [ 0 ]; CellRange cell = sheet . Range [ "B2" ]; cell . Text = "Texture Background" ; // Angle texture pattern cell . Style . FillPattern = ExcelPatternType . Angle ; cell . Style . Color = Color . LightGray ; // Base background color cell . Style . PatternColor = Color . Beige ; // Pattern overlay color workbook . SaveToFile ( "CellPattern.xlsx" , ExcelVersion . Version2016 ); } N

.NET 10 NU1015 turns a PackageReference without a version into a restore error. I like the stricter default because an unbounded direct dependency can quietly resolve the lowest package version. The catch is that versionless XML is also the correct shape for NuGet Central Package Management (CPM). A mechanical “add Version everywhere” repair can undo the policy your repository intended to enforce. I use a simple split: first decide who owns the version, then make restore prove the answer. Why .NET 10 NU1015 stops the build Before .NET 10, NuGet reported NU1604 when a direct reference had no inclusive lower bound. Restore could continue and select the lowest version available from the configured sources. Starting with .NET 10, the same mistake produces NU1015 and restore fails. Microsoft documents this as a stable behavioral change in the .NET 10 compatibility guidance . Here is the ambiguous project entry: <ItemGroup> <PackageReference Include= "Demo.Greeting" /> </ItemGroup> If this is a normal direct reference, the project is missing its version. If CPM is active, the project is correct and the version should live elsewhere. The NU1015 diagnostic reference calls out a common failure mode: a project that expected CPM was copied into a location where CPM is disabled or its props file is no longer discovered. That distinction matters more than silencing the error. It tells me whether the project file or the repository-level package policy is broken. The timing can be misleading. An SDK upgrade may expose an old direct reference that had always relied on lowest-version resolution, while a repository move may break a previously valid CPM import. I inspect the failing project's evaluated inputs, nearby props files, and recent path changes before editing package metadata. That keeps a restore migration from turning into an accidental package-management migration. Fix the owner, not only the XML For a direct reference, I add an explicit version: <PackageReference Include=

The .NET 10 JSON console logging change is small enough to miss during an upgrade: the formatted message still exists, but a typical record no longer duplicates it at State.Message . A collector, script, or snapshot test that reads only that nested property can start returning null while the application continues logging normally. I treat console JSON as a schema whenever another process parses it. That means a runtime upgrade deserves a contract test, not just a visual check in a terminal. The practical fix is to read the top-level Message , keep State for structured values, and retain a narrow fallback for older records. Why .NET 10 JSON console logging breaks nested-message parsers Before .NET 10, a normal AddJsonConsole record commonly repeated the rendered text: { "Message" : "Order 42 moved to ready." , "State" : { "Message" : "Order 42 moved to ready." , "OrderId" : 42 , "Status" : "ready" , "{OriginalFormat}" : "Order {OrderId} moved to {Status}." } } In .NET 10, the typical shape keeps one rendered message at the top level: { "Message" : "Order 42 moved to ready." , "State" : { "OrderId" : 42 , "Status" : "ready" , "{OriginalFormat}" : "Order {OrderId} moved to {Status}." } } Microsoft documents this as a behavioral breaking change and recommends that parsers use the top-level property. The official compatibility note also gives an essential caveat: State.Message may still appear when its content differs from the top-level value. I therefore do not reject a record merely because both properties exist. This is not a loss of structured logging data. OrderId , Status , and {OriginalFormat} remain useful fields inside State . The part that changed is where a consumer should get the rendered sentence. Prefer the top-level Message and keep State structured A legacy-only extractor is brittle because it assumes the duplicate is the contract: static string ? ReadLegacyOnly ( JsonElement root ) => root . TryGetProperty ( "State" , out var state ) && state . TryGetPro

A failure message can be technically correct and still be frustratingly incomplete. Consider a timeout. It tells us something important about the failure mechanism, but not which operation encountered it. Adding the complete request target might answer that question, yet it can also expose identifiers, query parameters, access material, or other data that never belonged in a broadly visible diagnostic record. A safer middle ground is to give failures two separate coordinates: a reason code that explains how the operation failed, and a bounded operation label that explains where it failed. That distinction makes diagnostics more useful without turning failure handling into an accidental data-exposure channel. A reason code is not a location Reason codes describe failure mechanics. Generic examples might include deadline , cancelled , unauthorised , or invalid_response . These codes are valuable because they let systems group similar outcomes. A dashboard can count deadline failures across operations, while application logic can decide whether a particular reason is retryable. What a reason code cannot reliably explain is the operation being attempted. A deadline during a summary read may require a different investigation from a deadline while assembling a detailed response. Combining both meanings into one free-form message makes failures harder to query and encourages presentation text to become an informal data model. Model the two coordinates separately A deliberately generic, invented C# model might look like this: public enum OperationArea { Summary , Detail , Archive } public sealed record FailureDetail ( string ReasonCode , OperationArea ? Area = null ); The reason remains suitable for classification. The operation label adds location without carrying an unrestricted request value. An enum is not the only option. A validated value object or centrally managed set of constants can work too. The important constraint is that labels come from a small, reviewed voca

The MCP C# SDK hybrid sessions option solves an awkward upgrade boundary: some clients still use the 2025-11-25 initialize handshake and depend on sessions, while clients on 2026-07-28 expect every HTTP request to stand alone. I want both groups to reach one ASP.NET Core endpoint without making modern clients downgrade or stripping useful behavior from legacy clients. The stable C# SDK 2.2.0 release added exactly that path with HttpServerSessionMode.StatefulForInitializeClients . The release notes describe it as hybrid stateful/stateless serving, and the official session-mode guide spells out the per-request behavior. Why one global session switch fails The 2026-07-28 MCP revision removed the initialize handshake and Mcp-Session-Id from its wire format. Client identity, capabilities, and protocol version travel with each request instead. The final specification announcement explains why the core moved toward request/response statelessness. That creates a migration choice for an existing server. With HttpServerSessionMode.Stateful , initialize-era clients receive full sessions. A modern request is refused so a dual-path client can fall back to the older handshake. Compatibility is preserved, but the client does not use the new protocol natively. With HttpServerSessionMode.Stateless , every request is independent. That is the right default for servers that do not need session state, unsolicited notifications, resource subscriptions, or older server-to-client flows. It may be too abrupt when deployed clients still rely on those features. Hybrid mode makes the decision from the incoming request instead of applying one choice to the endpoint. Configure MCP C# SDK hybrid sessions The server configuration is deliberately small: builder . Services . AddMcpServer () . WithHttpTransport ( options => { options . SessionMode = HttpServerSessionMode . StatefulForInitializeClients ; }) . WithTools < DemoTools >(); app . MapMcp ( "/mcp" ); An initialize-era client sends an initial

MCP x-mcp-header validation is easy to miss because the annotation looks like ordinary JSON Schema metadata. On the 2026-07-28 Streamable HTTP transport, it is a wire contract: the client copies selected tool arguments into Mcp-Param-* headers, intermediaries can act on those headers, and the server checks them against the JSON-RPC body. I treat that contract as something to test before a tool reaches tools/list . A bad suffix, an unsupported type, or an unreachable annotation makes the whole tool definition invalid. Silently accepting it only moves the failure to a harder place to diagnose. Why the same value travels twice The final Streamable HTTP specification mirrors request metadata into HTTP headers so a load balancer, gateway, or WAF does not need to parse JSON-RPC. A server can add x-mcp-header to a tool property: { "type" : "object" , "properties" : { "region" : { "type" : "string" , "x-mcp-header" : "Region" } } } A call with "region": "us-west1" then carries: Mcp-Param-Region: us-west1 The official C# SDK can generate that schema from a parameter attribute: [ McpServerTool ] public static string ExecuteSql ( [ McpHeader ( "Region" )] string region , string query ) => $"Queued for { region } " ; Current C# SDK v2 tool documentation describes both schema generation and automatic header projection. The feature is on the stable v2 line; it is not necessary to pin an earlier preview or release candidate. MCP x-mcp-header validation rules The final tool definition rules are deliberately narrow. The annotation value must be a non-empty HTTP field-name token and must be unique without regard to case. Region and region therefore collide. Control characters, spaces, and separators such as a colon are not valid suffix characters. Only string , integer , and boolean properties can be mirrored. JSON Schema number is excluded, and integer values must stay between -(2^53 - 1) and 2^53 - 1 so every conforming implementation can represent the value exactly. Reachability i

Microsoft did the hard work so you don't have to. The Microsoft.FeatureManagement library integrates directly with .NET's configuration and dependency injection systems, which means you can get feature flags working with minimal code and a solid foundation. For the full documentation, check out the Microsoft Feature Management documentation . Let's get this thing running. Installation Add the NuGet package to your project: dotnet add package Microsoft.FeatureManagement.AspNetCore That's it for dependencies. No magic rituals required. Configuration Register the feature management services in Program.cs : builder . Services . AddFeatureManagement (); By default, feature flags are read from the FeatureManagement section of your appsettings.json : { "FeatureManagement" : { "NewDashboard" : true , "ExperimentalSearch" : false } } Flag names are strings. Values are booleans. Simple. Checking a Flag in Code Inject IFeatureManager wherever you need to check a flag: public class DashboardController : Controller { private readonly IFeatureManager _featureManager ; public DashboardController ( IFeatureManager featureManager ) { _featureManager = featureManager ; } public async Task < IActionResult > Index () { if ( await _featureManager . IsEnabledAsync ( "NewDashboard" )) { return View ( "NewDashboard" ); } return View ( "OldDashboard" ); } } That's the whole pattern. Inject. Check. Branch. Repeat. Using Feature Filters Boolean flags are useful, but sometimes you need something a little more sophisticated. The library supports feature filters for things like: Percentage rollouts Time windows User targeting For example, you can enable a feature for a percentage of requests: { "FeatureManagement" : { "BetaFeature" : { "EnabledFor" : [ { "Name" : "Percentage" , "Parameters" : { "Value" : 20 } } ] } } } This enables BetaFeature for 20% of requests. The library handles the sampling. You handle the business logic. Everybody wins. Razor Tag Helpers Building a Razor-based UI? The lib

xUnit 4.0.0 makes full test-case parallelization an explicit option. That is useful, but xUnit 4 ParallelMode.All changes a quiet assumption in many suites: tests in the same class, including separate rows of one theory, may now overlap. A static fake, shared fixture, temporary file, or database record that was safe under collection-level parallelism can become a race. I treat this as an isolation change, not a speed switch. Before enabling it across a suite, I want a deterministic failure that proves the risk and a deterministic check for each guardrail. What xUnit 4 ParallelMode.All changes The xUnit.net v3 4.0.0 release notes describe full test-case parallelization as a new feature. The default is still ParallelMode.Collections , so upgrading does not silently enable the broader mode. I have to opt in at the assembly level: using Xunit.Sdk ; using Xunit.v3 ; [ assembly : Parallelization ( Mode = ParallelMode . All , MaxThreads = 2 , Algorithm = ParallelAlgorithm . Conservative )] With Collections , tests within a collection are serialized. With All , every test case is eligible to run beside every other test case. That includes two cases from the same class and two pre-enumerated rows from the same theory. The official parallel test execution guide documents the modes, algorithms, and available opt-out scopes. I set MaxThreads = 2 in the sample so the scheduling condition is easy to inspect. It is a demonstration setting, not a recommendation for CI. The right value depends on available CPU, memory, and the external systems touched by the tests. Before changing the mode, I scan for mutable static fields, IClassFixture and ICollectionFixture implementations, fixed file names, environment-variable changes, test servers bound to fixed ports, and records addressed by shared IDs. I also check theory data sources for objects that rows can mutate. That inventory tells me whether the resource should become concurrency-safe, receive a unique per-test identity, or stay beh

When every unauthorized request becomes the same dashboard line, diagnosis turns into guessing. ASP.NET Core 10 authentication metrics give me a better split: did the handler have nothing to authenticate, reject supplied credentials, or accept them? That distinction matters because a client deployment that drops credentials needs a different response from a surge of malformed or expired credentials. ASP.NET Core 10 added built-in authentication and authorization instruments to System.Diagnostics.Metrics . I can collect them without rewriting each handler, and I can lock their behavior into an offline test before wiring up a production exporter. Why one 401 hides two different problems A protected endpoint normally challenges an unauthenticated caller. The final status is 401 whether the caller sent nothing or the handler rejected what it received. The authentication duration histogram exposes the missing context through aspnetcore.authentication.result : Result What the handler reported A common interpretation none No authentication result No applicable credentials were available failure Authentication failed Supplied credentials were rejected or processing failed success A principal was created Authentication completed successfully _OTHER Another framework result Preserve it as an explicit catch-all none is a handler result, not a universal synonym for “missing Authorization header.” A policy scheme or custom handler can make a different choice. I verify the behavior of the schemes I actually deploy instead of building an alert from the label alone. Likewise, success means the handler produced an authentication ticket. Authorization can still deny that principal, so it does not promise a 2xx response. The separate aspnetcore.authentication.challenges counter answers another question: how often was a scheme challenged? Both a none result and a failure result can be followed by a challenge, so challenge count cannot replace the result split. A challenge is an authent

A two-factor flag in the user store looks like a reassuring authorization check. It tells us the account has a second factor configured. For a sensitive operation, however, that is only half the question. The other half is about the session in front of us: did this cookie actually complete a second-factor challenge? Those facts can change independently. Treating them as interchangeable can silently promote an old password-only session after the account enables MFA. Two questions that look like one Account capability answers questions such as: Is a factor enrolled now? Could the account complete an MFA challenge? Has that capability since been disabled? Session assurance answers different questions: Which authentication steps produced this session? Did the framework issue this cookie after an MFA challenge? Is the evidence trusted, or merely a user-supplied claim? An enrolled account can still have a password-only session. A previously verified session can also outlive a later change to the account’s factor state. One signal cannot safely stand in for both. The transition that exposes the gap Snapshot tests often miss this because the final state looks correct. The account has MFA enabled, the user is authenticated, and a policy succeeds. Now test the transition instead: Sign in with a password and receive a normal application cookie. Enable MFA for the account without replacing that cookie. Use the original cookie against a sensitive operation. If authorization checks only the current enrolment flag, step three may succeed. Nothing about the original authentication ceremony changed, but the session has effectively been upgraded by a later database write. That is the important boundary: changing account capability must not rewrite the history of an already-issued session. Use two independent signals A generalized policy can be expressed like this: if (! session . IsAuthenticated || ! session . HasTrustedMfaEvidence ) return Deny ; if (! await accountStore . IsMfaStil

Imagine this: You’re drafting a long email, writing a report, or responding to a wave of Slack messages. Instead of hunching over your keyboard and typing at 40 words per minute, you simply hold down Ctrl + Space , speak your thoughts at 150+ words per minute, and release the keys. Instantly, clean, perfectly punctuated, polished text appears right where your cursor is. Meet Vacanam — a free, 100% private, offline voice typing tool built for Windows 10 & 11. 😫 Why Most Voice Typing Tools Are Frustrating If you’ve ever tried built-in dictation tools or commercial transcription services, you’ve likely run into the same annoyances: They Send Your Voice to the Cloud : Many tools stream your microphone audio to remote servers. If you work with sensitive emails, client data, or private thoughts, that’s an immediate dealbreaker. They Require an Internet Connection : Try dictating on an airplane, during spotty Wi-Fi, or in a secure offline room — they simply refuse to work. Punctuation is a Headache : You have to awkwardly say things like "Hello comma how are you question mark" just to get a basic sentence right. Subscription Fatigue : Most good dictation apps charge $10 to $30 every single month. We built Vacanam (वचनम् — Sanskrit for Voice & Speech ) to fix all of this once and for all. 🌟 The Superpowers: What Makes Vacanam Different? 1. 🎙️ Works in Every Single Windows App Vacanam doesn’t trap you inside a special recording window. It works universally: Productivity & Docs : Microsoft Word, Google Docs, Notion, Obsidian, OneNote Communication : Slack, Microsoft Teams, WhatsApp Desktop, Discord, Outlook, Gmail Browsers & Editors : Chrome, Edge, Firefox, Notepad, VS Code, Terminals Just click into any text box, hold Ctrl + Space, speak, and let go. 2. 🪄 Automatic AI Polish (No More "Ums" or Missing Commas) When we talk, we hesitate, say "um" , repeat words, and forget punctuation. Vacanam features an optional Built-in AI Assistant that runs silently on your computer: Remov

Hello I'm Marlene and I invite you to follow my journey developing ProForma.net. But since this is my first post about ProForma, I will give you an overview of what I'm trying to achieve. What ProForma.net is planned to be The main Goal is to develop an application shell for schema based Applications. You will have mainly to different types of UI schemes, first for the Window Layout, there you will tell which elements are contained in the different application sections, like what Buttons or Menus you will have in the window title bar, or what sidebar tabs you will provide for the Ribbons, what the content area is filled with (spoiler I'm going to use flexlayout-react https://github.com/caplin/FlexLayout ). As host application I will write a C# application using the WebView2 abstraction library Photino ( https://www.tryphotino.io/ ). What you can expect In this dev diary series I'll show what I was working on, I'll show you some code and will explain why did to choose the way I did it, or will share some thoughts about the project or the architecture. I also will show you how to write plugins for ProForma, because I plan to handle everything as a plugin so you can change the most aspects of the app. The journey begins: overcome the guard Ok, most of you will know it... parameter checking on top of a method... nearly endless 'if throw' constructs... they are ugly... if (! Directory . Exists ( physicalPath )) throw new DirectoryNotFoundException ( $"Could not find the given path ' { physicalPath } '." ); if ( _directories . ContainsKey ( urlPrefix )) throw new Exception ( $"Key ' { urlPrefix } ' already exists." ); if ( _directories . ContainsValue ( physicalPath )) throw new Exception ( $"Physical Path ' { physicalPath } ' already exists." ); I mean who wants to read that? I don't. So I wanted guards, and I've could used some 3rd Party library, but instead I came up with my own solution for the Guards, since I don't always want to throw the exception on a failed asser

A build note from Horizon Software , a one-person Android studio. WanderWallet is a travel budget app, and the whole thing runs on the phone: no account, no backend, no cloud. Here's how the parts that look like they need a server actually work without one. The one constraint that shaped everything WanderWallet has a single non-negotiable rule: it has to work with no signal. You're three countries into a trip, your phone's in airplane mode to dodge roaming charges, and you still need to know whether you're on budget. That one requirement quietly makes most of the architectural decisions for you — no login, no server round-trips, and every feature that would normally lean on a cloud API has to earn its keep another way. The stack is deliberately boring: .NET MAUI (Android-first), CommunityToolkit.Mvvm , sqlite-net-pcl for storage, and SkiaSharp for anything I draw myself. Everything the app records lives in a local SQLite database on the device and nowhere else. "Backup" is a file you export and keep — there's no server to back up to . The three features people assume need a backend turned out to be the most interesting to build, precisely because they don't. 1. Currency conversion that survives airplane mode A travel budget app that can't convert currencies offline is useless at exactly the moment you need it. So rates aren't fetched on demand. Whenever the app happens to have a connection it refreshes exchange rates for ~155 currencies and caches the whole table locally . From then on every conversion is local arithmetic — a connection only ever buys you a fresher table, never the ability to convert. The design decision that took me longest to get right: capture the conversion immutably, at entry time. Each expense stores the original amount, its original currency, the converted home-currency amount, and the exact rate used — and that rate is never recalculated: public class Expense { public double Amount { get ; set ; } // in OriginalCurrency public string Origina