# scheme Published articles for scheme. This is one page of public article previews, not the complete archive. Follow Next page to continue. Summaries are not the original full articles. ## Modern CSS theming with light-dark(), contrast-color(), and style queries DevFeed: [Modern CSS theming with light-dark(), contrast-color(), and style queries]() Original publisher: [Read original article]() Published: 2026-06-22T00:00:00Z Content type: tutorial Language: en Sources: [Una Kravets]() Topics: [CSS](), [modern web development](), [color](), [Media Queries]() Tags: [color](), [css](), [dark-mode](), [dynamic-theming](), [media](), [scheme](), [support](), [themes]() ### AI overview This tutorial explains how to combine light-dark(), contrast-color(), style queries, custom properties, and related CSS color features to create adaptive themed components. It covers light and dark color schemes, context-sensitive palettes, automatic text contrast, and different elevation effects for each theme. ### Source excerpt Combine three new CSS features to build fully adaptive themed components. ## wastrel milestone: full hoot support, with generational gc as a treat DevFeed: [wastrel milestone: full hoot support, with generational gc as a treat]() Original publisher: [Read original article]() Author: Andy Wingo Published: 2026-04-09T13:48:04Z Content type: article Language: en Sources: [wingolog]() Topics: [WebAssembly](), [scheme](), [toolchain](), [gcc]() Tags: [binaries](), [garbage-collection](), [gc](), [gcc](), [hoot](), [optimization](), [repl](), [scheme](), [spidermonkey](), [toolchain](), [treats](), [v8](), [wasm](), [wastrel](), [web](), [webassembly]() ### AI overview The article describes a Wastrel milestone: compiling WebAssembly files produced by the Hoot Scheme toolchain into native binaries, including a console-based read-eval-print loop. It covers the build process, runtime modules, binary size, dependencies, and initial performance observations. ### Source excerpt Hear ye, hear ye: Wastrel and Hoot means REPL! Which is to say, Wastrel can now make native binaries out of WebAssembly files as produced by the Hoot Scheme toolchain, up to and including a full read-eval-print loop. Like the REPL on the Hoot web page, but instead of requiring a browser, you can just run it on your console. Amazing stuff! try it at home First, we need the latest Hoot. Build it from source, then compile a simple REPL: echo '(import (hoot repl)) (spawn-repl)' > repl.scm ./pre-inst-env hoot compile -fruntime-modules -o repl.wasm repl.scm This takes about a minute. The resulting wasm file has a pretty full standard library including a full macro expander and evaluator. Normally Hoot would do some aggressive tree-shaking to discard any definitions not used by the program, but with a REPL we don't know what we might need. So, we pass -fruntime-modules to instruct Hoot to record all modules and their bindings in a central registry, so they can be looked up at run-time. This results in a 6.6 MB Wasm file; with tree-shaking we would have been at 1.2 MB. Next, build Wastrel from source, and compile our new repl.wasm: wastrel compile -o repl repl.wasm This takes about 5 minutes on my machine: about 3 minutes to generate all the C, about 6.6MLOC all in all, split into a couple hundred files of about 30KLOC each, and then 2 minutes to compile with GCC and link-time optimization (parallelised over 32 cores in my case). I have some ideas to golf the first part down a bit, but the the GCC side will resist improvements. Finally, the moment of truth: $ ./repl Hoot 0.8.0 Enter `,help' for help. (hoot user)> "hello, world!" => "hello, world!" (hoot user)> statics When I first got the REPL working last week, I gasped out loud: it's alive, it's alive!!! Now that some days have passed, I am finally able to look a bit more dispassionately at where we're at. Firstly, let's look at the compiled binary itself. By default, Wastrel passes the -g flag to GCC, which results in bi ## Wastrel Compiles Hoot Scheme-to-WebAssembly Output DevFeed: [Wastrel Compiles Hoot Scheme-to-WebAssembly Output]() Original publisher: [Read original article]() Author: Andy Wingo Published: 2026-03-31T20:34:23Z Content type: article Language: en Sources: [wingolog]() Topics: [WebAssembly](), [Compiler](), [scheme]() Tags: [accidentally-quadratic](), [aot](), [bigint](), [bignums](), [compiler](), [compilers](), [exception-handling](), [exceptions](), [gc](), [gcc](), [gmp](), [hoot](), [igalia](), [library](), [maps](), [precision](), [scheme](), [standard](), [tail-calls](), [wasm](), [wastrel](), [webassembly](), [whippet]() ### AI overview The article describes recent work on Wastrel, an ahead-of-time WebAssembly compiler, including compiling output from the Hoot Scheme-to-Wasm compiler. It covers implementing bignum operations with mini-gmp and updating Hoot to use standardized WebAssembly exception handling. ### Source excerpt Good day! Today (tonight), some notes on the last couple months of Wastrel, my ahead-of-time WebAssembly compiler. Back in the beginning of February, I showed Wastrel running programs that use garbage collection, using an embedded copy of the Whippet collector, specialized to the types present in the Wasm program. But, the two synthetic GC-using programs I tested on were just ported microbenchmarks, and didn't reflect the output of any real toolchain. In this cycle I worked on compiling the output from the Hoot Scheme-to-Wasm compiler. There were some interesting challenges! bignums When I originally wrote the Hoot compiler, it targetted the browser, which already has a bignum implementation in the form of BigInt, which I worked on back in the day. Hoot-generated Wasm files use host bigints via externref (though wrapped in structs to allow for hashing and identity). In Wastrel, then, I implemented the imports that implement bignum operations: addition, multiplication, and so on. I did so using mini-gmp, a stripped-down implementation of the workhorse GNU multi-precision library. At some point if bignums become important, this gives me the option to link to the full GMP instead. Bignums were the first managed data type in Wastrel that wasn't defined as part of the Wasm module itself, instead hiding behind externref, so I had to add a facility to allocate type codes to these "host" data types. More types will come in time: weak maps, ephemerons, and so on. I think bignums would be a great proposal for the Wasm standard, similar to stringref ideally (sniff!), possibly in an attenuated form. exception handling Hoot used to emit a pre-standardization form of exception handling, and hadn't gotten around to updating to the newer version that was standardized last July. I updated Hoot to emit the newer kind of exceptions, as it was easier to implement them in Wastrel that way. Some of the problems Chris Fallin contended with in Wasmtime don't apply in the Wastrel case: sinc ## two mechanisms for dynamic type checks DevFeed: [two mechanisms for dynamic type checks]() Original publisher: [Read original article]() Author: Andy Wingo Published: 2026-02-18T16:21:10Z Content type: tutorial Language: en Sources: [wingolog]() Topics: [virtual machines](), [Inheritance](), [WebAssembly](), [JIT](), [Polymorphism]() Tags: [cardelli](), [cohen](), [dfs](), [display-hack](), [dybvig](), [scheme](), [vitek](), [wasm](), [webassembly]() ### AI overview This technical note explains two mechanisms for dynamic instance type checks in virtual machines with single inheritance. It describes DFS numbering when the type set is fixed and the display hack, based on per-type supertype arrays, when types can be added at run time. ### Source excerpt Today, a very quick note on dynamic instance type checks in virtual machines with single inheritance. The problem is that given an object o whose type is t, you want to check if o actually is of some more specific type u. To my knowledge, there are two sensible ways to implement these type checks. if the set of types is fixed: dfs numbering Consider a set of types T := {t, u, ...} and a set of edges S := {, ...} indicating that t is the direct supertype of u, or ε if u is a top type. S should not contain cycles and is thus a direct acyclic graph rooted at ε. First, compute a pre-order and post-order numbering for each t in the graph by doing a depth-first search over S from ε. Something like this: def visit(t, counter): t.pre_order = counter counter = counter + 1 for u in S[t]: counter = visit(u, counter) t.post_order = counter return counter Then at run-time, when making an object of type t, you arrange to store the type's pre-order number (its tag) in the object itself. To test if the object is of type u, you extract the tag from the object and check if tag-u.pre_order mod 2n < u.post_order-u.pre_order. Two notes, probably obvious but anyway: one, you know the numbering for u at compile-time and so can embed those variables as immediates. Also, if the type has no subtypes, it can be a simple equality check. Note that this approach applies only if the set of types T is fixed. This is the case when statically compiling a WebAssembly module in a system that doesn't allow modules to be instantiated at run-time, like Wastrel. Interestingly, it can also be the case in JIT compilers, when modeling types inside the optimizer. if the set of types is unbounded: the display hack If types may be added to a system at run-time, maintaining a sorted set of type tags may be too much to ask. In that case, the standard solution is something I learned of as the display hack, but whose name is apparently ungooglable. It is described in a 4-page technical note by Norman H. Coh ## Schema-Guided Reasoning: как научить языковые модели последовательно рассуждать DevFeed: [Schema-Guided Reasoning: как научить языковые модели последовательно рассуждать]() Original publisher: [Read original article]() Author: redmadrobot (red\_mad\_robot) Published: 2025-10-31T16:31:44Z Content type: tutorial Language: ru Sources: [Redmadrobot EN](), [Redmadrobot RU]() Topics: [Large Language Model](), [Structured-data](), [Artificial Intelligence](), [JSON](), [Pydantic]() Tags: [function-calling](), [json](), [llm](), [reasoning](), [schema](), [scheme](), [sgr](), [structured-output](), [tag-1cd610c0e518](), [tag-5335b6f99fba](), [tag-b0a411324cb6]() ### AI overview This tutorial explains Schema-Guided Reasoning (SGR), an approach that guides large language models through predefined schemas. It describes how structured output, Pydantic models, JSON schemas, and constrained decoding can make model responses more consistent, transparent, and easier to test, while noting that SGR is not a universal solution. ### Source excerpt LLM умеют многое: генерировать тексты, анализировать документы, писать код. Но на практике их работа часто непредсказуема -- сегодня модель даёт точный ответ, а завтра на тех же данных ошибается, пропускает ключевые шаги или придумывает факты. Для AI-инженеров это системная проблема. Возьмём автоматизацию документооборота: нужно классифицировать договоры, извлекать реквизиты, проверять стандарты. Но модель работает как лотерея -- результат не поддаётся логике или меняется при повторном запуске с одинаковыми данными. Как встроить такой результат в бизнес-процесс? Для решения этой задачи появился подход Schema-Guided Reasoning (SGR). Его активно продвигает Ринат Абдуллин в материалах по работе с LLM. Идея проста и эффективна: заставить модель мыслить не хаотично, а внутри заданной схемы. Это не панацея, но SGR серьёзно снижает количество ошибок, делает процесс прозрачнее, а также позволяет тестировать отдельные компоненты рассуждений. Читать далее ## SwiftUI Custom URL Schemes DevFeed: [SwiftUI Custom URL Schemes]() Original publisher: [Read original article]() Author: Keith Harrison Published: 2025-10-27T11:26:47Z Content type: tutorial Language: en Sources: [K. Harrison]() Topics: [SwiftUI](), [WebView](), [iOS](), [WebKit](), [App]() Tags: [async](), [auto-layout](), [configuration](), [how-to](), [ios](), [ios-26](), [objective-c](), [protocol](), [scheme](), [swift](), [swiftui](), [web](), [webview](), [wwdc](), [xcode]() ### AI overview This tutorial explains how to create a custom URL scheme handler for SwiftUI WebViews in iOS 26. It covers implementing URLSchemeHandler, loading local HTML resources from an app bundle, registering the handler in a WebPage configuration, and displaying the page in a WebView. ### Source excerpt Create a custom URL scheme handler for SwiftUI WebViews. Custom URL schemes Apple introduced both WebView and WebPage SwiftUI views in iOS 26. These provide similar WebKit functionality to the UIKit WKWebView APIs. This includes being able to register custom URL schemes to load local resources. Suppose I have an App that loads quotations from the local App bundle. My URL scheme uses the format: quotes://001.html There are a few steps to support a custom URL scheme: Create a custom URL scheme handler that knows how to load the local resources. Register the scheme handler in a WebPage configuration. Have the WebView load and display the web page. Let's look at each of those steps. URLSchemeHandler (iOS 26) The URLSchemeHandler is a protocol with a reply method to return an async sequence of results. The AsyncSequence expects us to either yield a URLResponse and some data or throw an error. struct QuoteSchemeHandler: URLSchemeHandler { static let scheme = "quotes" func reply(for request: URLRequest) -> some AsyncSequence< URLSchemeTaskResult, any Error > { AsyncThrowingStream { continuation in ... } } } The reply method provides us with the URLRequest. I start by extracting the URL and checking it matches our quotes scheme: guard let url = request.url else { continuation.finish(throwing: QuoteError.missingURL) return } guard url.scheme == QuoteSchemeHandler.scheme else { continuation.finish(throwing: QuoteError.invalidScheme) return } To construct the URL response I need the mime type and length of the data. I first extract the filename from the URL, determine the mime type from the file extension, and then load the data: do { let file = try filename(for: url) let mimeType = try mimeType(for: file) let data = try Data(contentsOf: file) I can then build the URLResponse: let response = URLResponse( url: url, mimeType: mimeType, expectedContentLength: data.count, textEncodingName: "utf-8" ) If nothing has gone wrong I then add the response and the data to the AsyncSequenc ## How to Resolve AT Protocol URIs DevFeed: [How to Resolve AT Protocol URIs]() Original publisher: [Read original article]() Author: The User As The Authority Published: 2025-10-02T00:00:00Z Content type: tutorial Language: en Sources: [Dan Abramov]() Topics: [AT Protocol](), [JSON](), [SDK](), [client]() Tags: [client](), [json](), [protocol](), [scheme](), [sdk]() ### AI overview This tutorial explains how to resolve AT Protocol URIs to the JSON data they represent. It covers URI structure, handle-to-identity resolution, locating the current hosting server, and inspecting the resulting data with SDKs or client applications. ### Source excerpt From handles to hosting. ## 🖤 Automatic Dark mode for Hugo using Tailwind CSS DevFeed: [🖤 Automatic Dark mode for Hugo using Tailwind CSS]() Original publisher: [Read original article]() Author: Kaushik Gopal Published: 2025-04-04T23:01:08Z Content type: tutorial Language: en Sources: [Kaushik Gopal's Site]() Topics: [Dark Mode](), [CSS](), [Tailwind CSS](), [Hugo](), [implementation]() Tags: [css](), [dark-mode](), [html5](), [hugo](), [implementation](), [scheme](), [tailwind](), [tailwind-css]() ### AI overview This tutorial explains how to add automatic dark-mode support to a Hugo site using Tailwind CSS 4.0 and the CSS prefers-color-scheme media feature. The implementation updates theme color variables and adds a dark class to the root HTML element. ### Source excerpt On a ✈ back home, I decided to add Dark mode support to Henry. Having recently upgraded to Tailwind CSS 4.0, this was a piece of cake to do. I leverage the widely supported CSS @media prefers-color-scheme feature and Tailwind's native dark-mode support. The implementation only required a few changes: 1. update main theme.css ### In my main theme.css file where I declare the existing colors, I add the CSS @media selector for the "dark" variable indicator. @theme { /* henry background */ --color-hbg: var(--color-slate-50); --color-hbg-dark: var(--color-slate-200); /* ... */ } @media (prefers-color-scheme: dark) { .dark { /* henry background */ --color-hbg: #1c2b33; --color-hbg-dark: #152027; /* ... */ } } 2. update base html body ### In my root html page, I simply add the "dark" variable indicator class Now CSS automatically knows to pull in the dark variant of colors when the system indicates light/dark mode. There is no step 3! Your browser doesn't support HTML5 video. Download the video instead. This was so easy to do, in fact, that I even managed to catch up on Gladiator II on the plane ride which I personally give a solid 3.0 just for Denzel. ## Using AI to aid color scheme migrations DevFeed: [Using AI to aid color scheme migrations]() Original publisher: [Read original article]() Author: Carlos Alexandro Becker Published: 2024-10-31T00:00:00Z Content type: tutorial Language: en Sources: [Carlos Becker]() Topics: [Artificial Intelligence](), [color](), [scheme](), [Claude](), [dotfiles](), [Terminal](), [Command-line interface]() Tags: [ai](), [claude](), [code](), [color](), [command-line](), [fzf](), [scheme](), [terminal]() ### AI overview A short practical post about using AI, especially Claude, to migrate color themes across dotfiles and developer tools. It demonstrates adapting a Catppuccin fzf theme to Gruvbox and suggests refactoring existing theme files with editor or command-line AI tools. ### Source excerpt Recently I found a good use case for AI when migrating my dotfiles to another theme. This is a short post about it. ## Encoding Schemes in FHE DevFeed: [Encoding Schemes in FHE]() Original publisher: [Read original article]() Published: 2023-09-18T11:08:39Z Content type: tutorial Language: en Sources: [Jeremy Kun]() Topics: [Encoding](), [FHE](), [homomorphic encryption](), [Cryptography](), [Decoding]() Tags: [bits](), [complex-numbers](), [cryptography](), [decoding](), [encoding](), [fhe](), [homomorphic-encryption](), [learning-with-errors](), [lwe](), [mathematics](), [number-theory](), [programming](), [residue-number-system](), [rlwe](), [scaling](), [scheme]() ### AI overview This article explains how cleartexts are transformed into plaintexts through encoding, and reversed through decoding, in homomorphic encryption. It catalogs encoding approaches for different HE schemes, including bit-field encoding for LWE and considerations for noise, scaling, bit positions, and programmable bootstrapping in CGGI/TFHE. ### Source excerpt In cryptography, we need a distinction between a cleartext and a plaintext. A cleartext is a message in its natural form. A plaintext is a cleartext that is represented in a specific way to prepare it for encryption in a specific scheme. The process of taking a cleartext and turning it into a plaintext is called encoding, and the reverse is called decoding. In homomorphic encryption, the distinction matters. Cleartexts are generally all integers, though the bit width of allowed integers can be restricted (e. ## Sample Extraction from RLWE to LWE DevFeed: [Sample Extraction from RLWE to LWE]() Original publisher: [Read original article]() Published: 2023-02-27T08:00:00Z Content type: tutorial Language: en Sources: [Jeremy Kun]() Topics: [FHE](), [Cryptography](), [Encryption]() Tags: [cryptography](), [encryption](), [fhe](), [homomorphic-encryption](), [linear-algebra](), [lwe](), [mathematics](), [programming](), [rlwe](), [scheme]() ### AI overview A tutorial deriving sample extraction, an FHE technique that partially converts a ciphertext from the Ring Learning With Errors (RLWE) scheme to the Learning With Errors (LWE) scheme. It introduces the relevant LWE and RLWE encryption constructions and explains the role of error terms. ### Source excerpt In this article I'll derive a trick used in FHE called sample extraction. In brief, it allows one to partially convert a ciphertext in the Ring Learning With Errors (RLWE) scheme to the Learning With Errors (LWE) scheme. Here are some other articles I've written about other FHE building blocks, though they are not prerequisites for this article. Modulus Switching in LWE Key Switching in LWE The Gadget Decomposition in FHE Negacyclic Polynomial Multiplication Estimating the Security of Ring Learning With Errors LWE and RLWE The first two articles in the list above define the Learning With Errors problem (LWE). ## Verkle tree structure DevFeed: [Verkle tree structure]() Original publisher: [Read original article]() Author: Guillaume Ballet; Dankrad Feist Published: 2021-12-02T00:00:00Z Content type: tutorial Language: en Sources: [Ethereum Foundation Blog]() Topics: [Code](), [client]() Tags: [developers](), [how-to](), [implement](), [introduction](), [layout](), [merge](), [post](), [research-development](), [scheme](), [stem](), [storage](), [structure](), [vector]() ### AI overview This developer article explains the structure of draft Verkle tree EIP designs. It describes replacing Merkle tree hashes with vector commitments, merging account and storage tries, using 32-byte keys, and organizing keys into 31-byte stems with one-byte suffixes. ### Source excerpt A Verkle tree is a commitment scheme that works similar to a Merkle tree, but has much smaller witnesses. It works by replacing the hashes in a Merkle tree with a vector commitment, which makes wider branching factors more efficient. Thanks to Kevaundray Wedderburn for feedback on the post.... ## Silencing iOS simulator log noise DevFeed: [Silencing iOS simulator log noise]() Original publisher: [Read original article]() Author: Keith Smiley Published: 2021-11-17T02:00:00Z Content type: tutorial Language: en Sources: [Keith Smiley]() Topics: [iOS](), [simulator](), [configuration]() Tags: [commands](), [configuration](), [ios](), [logs](), [scheme](), [simulator](), [streaming]() ### AI overview This article explains how to reduce noisy iOS simulator logs without disabling os_log entirely. It recommends using log configuration commands to disable selected subsystems or categories and describes targeting either the booted simulator or a specific simulator UDID. ### Source excerpt When Apple transitioned to using os_log for system logs it seemed they also decided to open the floodgates for what logs were surfaced in our apps. This lead to a plethora of stackoverflow questions recommending you disable os_log entirely by setting OS_ACTIVITY_MODE=disable in your target's scheme. This is fine for some cases but might also silence some actually useful logs, or your own logs if you want to use os_log for its feature-set. os_log has a nice set of categorization for logs, for example when viewing streaming logs in Console.app you can show the process, subsystem, and category for each log. Perhaps ideally we could use an environment variable with more granular filtering based on this categorization, but that would likely get complex quickly. Instead we can update OS log's configuration to disable some specific types of logs. Here are a few examples I found useful for Lyft's iOS project: xcrun simctl spawn booted log config --subsystem com.apple.CoreBluetooth --mode level:off xcrun simctl spawn booted log config --subsystem com.apple.CoreTelephony --mode level:off xcrun simctl spawn booted log config --subsystem com.apple.network --category boringssl --mode level:off You can replace booted here with a specific iOS simulator UDID, which can be found by running xcrun simctl list devices. Since this is simulator specific, you will have to re-run whatever commands you decide on when you create new simulators. More options for the log command can be found with man log ## Turn on debug output in SVN DevFeed: [Turn on debug output in SVN]() Original publisher: [Read original article]() Author: Graham King Published: 2009-05-07T23:02:38Z Content type: tutorial Language: en Sources: [Graham King]() Topics: [debug](), [client](), [Authentication](), [repo](), [scheme]() Tags: [authentication](), [client](), [debug](), [repo](), [scheme](), [software](), [upgrade]() ### AI overview A troubleshooting guide explains how to enable Subversion debug output when an SVN client repeatedly requests credentials after a desktop and server upgrade. The reported cause involves an Apache AuthDigestDomain configuration that requires a scheme, although the relevant commands and full configuration values are missing from the supplied text. ### Source excerpt After a desktop and server upgrade, my subversion client stopped working. I am using Digest authentication, and it kept asking me for the username and password. Wireshark showed me that the SVN client wasn't sending the Authentication header. To find out more, I turned on Subversion's debug output. Here's how you do it: Edit Add this line at the end: That showed me this error: This means that the path I was requesting (the root of the repo) was not considered inside the I had set in Apache. ## JScheme DevFeed: [JScheme]() Original publisher: [Read original article]() Published: 2005-08-08T00:00:00Z Content type: tutorial Language: en Sources: [Peter Norvig]() Topics: [Java](), [scheme](), [Programming language](), [implementation](), [Programming]() Tags: [implementation](), [java](), [language](), [programming](), [programming-language](), [scheme]() ### AI overview This page documents Jscheme, an implementation of the Scheme programming language in Java. It describes version 1.4, its compatibility with R4RS Scheme, known limitations, and planned features such as improved error handling, Java integration, multithreading, web access, GUI support, and R5RS support. ### Source excerpt An implementation of the Scheme programming language in Java.