https://cogway.dev/ Interactive explainers for Laravel and PHP. One concept at a time, turned into something you can step through, break, and run again. en Sat, 26 Sep 2026 00:00:00 GMT https://cogway.dev/explainers/agent-tool-loop/ https://cogway.dev/explainers/agent-tool-loop/ prompt() is a loop. Every pass resends your instructions, your tool schemas and the whole conversation, so three tool calls cost four provider requests. Sat, 26 Sep 2026 00:00:00 GMT https://cogway.dev/explainers/partial-application/ https://cogway.dev/explainers/partial-application/ The arguments you supply around a placeholder are evaluated once, when you create the partial, and frozen into it for every call after that. Sat, 26 Sep 2026 00:00:00 GMT https://cogway.dev/explainers/confidence-threshold/ https://cogway.dev/explainers/confidence-threshold/ A threshold only tests the number the model states about itself. Against a model that states 0.95 on everything, no setting of the dial excludes the mistakes. Sun, 20 Sep 2026 00:00:00 GMT https://cogway.dev/explainers/container-binding/ https://cogway.dev/explainers/container-binding/ bind builds a new instance every time, singleton keeps one for as long as the container lives, and scoped keeps one per request. On a persistent worker that difference is a data leak between requests. Sat, 19 Sep 2026 00:00:00 GMT https://cogway.dev/explainers/row-locks-deadlock/ https://cogway.dev/explainers/row-locks-deadlock/ An update with no index on the filtered column locks every row it scanned, not the rows it changed. And a lock wait timeout kills one statement, while a deadlock kills the whole transaction. Sat, 19 Sep 2026 00:00:00 GMT https://cogway.dev/explainers/array-keys/ https://cogway.dev/explainers/array-keys/ A PHP array is an ordered hashmap, and a list is only an appearance its keys give it. Remove one element and json_encode changes the shape of your API response, with nothing to warn you. Fri, 18 Sep 2026 00:00:00 GMT https://cogway.dev/explainers/model-events/ https://cogway.dev/explainers/model-events/ An observer runs when a model changes, not when a row changes. A query builder update writes every matching row and fires nothing, so whatever the observer kept in step is now behind. Fri, 18 Sep 2026 00:00:00 GMT https://cogway.dev/explainers/bytes-vs-characters/ https://cogway.dev/explainers/bytes-vs-characters/ A PHP string is a row of bytes, not a row of characters. strlen counts bytes, mb_strlen counts code points, and grapheme_strlen counts what a reader can see. Cutting with the wrong one breaks the text in two different ways. Tue, 15 Sep 2026 00:00:00 GMT https://cogway.dev/explainers/chunk-skips-rows/ https://cogway.dev/explainers/chunk-skips-rows/ chunk() pages with LIMIT and OFFSET and re-runs the query each time. Write to the column you filtered on and rows shift out from under it, so the next offset starts past rows nobody ever visited. Tue, 15 Sep 2026 00:00:00 GMT https://cogway.dev/explainers/catastrophic-backtracking/ https://cogway.dev/explainers/catastrophic-backtracking/ A nested quantifier makes the number of paths double with every letter, and it is the failing input that is slow. PHP gives up and returns false. Wed, 05 Aug 2026 00:00:00 GMT https://cogway.dev/explainers/magic-methods/ https://cogway.dev/explainers/magic-methods/ Magic methods do not run first. A declared, accessible member always wins, and __get and __call are only the fallback when ordinary lookup finds nothing. Wed, 05 Aug 2026 00:00:00 GMT https://cogway.dev/explainers/middleware-pipeline/ https://cogway.dev/explainers/middleware-pipeline/ Middleware is not a list of filters run once on the way in. Each one wraps the request and the response, so the after halves run in reverse. Wed, 05 Aug 2026 00:00:00 GMT https://cogway.dev/explainers/sanctum-token-vs-session/ https://cogway.dev/explainers/sanctum-token-vs-session/ Sanctum authenticates two callers behind one guard: your own SPA by session cookie, a mobile client by bearer token. A token in your own SPA is the mistake. Wed, 05 Aug 2026 00:00:00 GMT https://cogway.dev/explainers/attribute-casting/ https://cogway.dev/explainers/attribute-casting/ Model columns are not typed properties. They live in an array of raw values, and $casts converts them on read. isDirty compares them cast, not only raw. Tue, 04 Aug 2026 00:00:00 GMT https://cogway.dev/explainers/cache-stampede/ https://cogway.dev/explainers/cache-stampede/ Cache::remember protects the database only while the value is warm. When a key expires, every concurrent request runs the callback. A lock collapses it to one. Tue, 04 Aug 2026 00:00:00 GMT https://cogway.dev/explainers/references-memory/ https://cogway.dev/explainers/references-memory/ PHP assigns arrays by value, but defers the copy until a write. A reference is the opposite: two names, one slot. Copy-on-write and the foreach trap follow. Sun, 02 Aug 2026 00:00:00 GMT https://cogway.dev/explainers/transaction-rollback/ https://cogway.dev/explainers/transaction-rollback/ A nested DB::transaction is a savepoint, not its own transaction. An inner commit runs no SQL, and nothing is durable until the outermost commit. Sun, 02 Aug 2026 00:00:00 GMT https://cogway.dev/explainers/event-sourcing/ https://cogway.dev/explainers/event-sourcing/ A projection is one of many views folded from the event stream. Add a projector after the fact, replay it, and it rebuilds from events that already existed. Sat, 01 Aug 2026 00:00:00 GMT https://cogway.dev/explainers/n-plus-one/ https://cogway.dev/explainers/n-plus-one/ with() is not an optimisation you sprinkle on. It changes when your queries happen. Drive the loop and watch the counter. Sat, 01 Aug 2026 00:00:00 GMT https://cogway.dev/explainers/queue-retries/ https://cogway.dev/explainers/queue-retries/ A thrown job is released and retried after a backoff. $tries counts total attempts, not retries. Killing the worker does not fail the job. Sat, 01 Aug 2026 00:00:00 GMT https://cogway.dev/explainers/type-juggling/ https://cogway.dev/explainers/type-juggling/ PHP's == does not compare values by eye. It coerces both sides to a common type first, following fixed rules, and one of those rules changed in PHP 8. Sat, 01 Aug 2026 00:00:00 GMT