webiny

api — 21 abstractions.

api/webhooks — 15 abstractions.

Admin-side architecture patterns for Webiny extensions. Use this skill when building frontend features with headless features (UseCase/Repository/Gateway), presentation features (Presenter/ViewModel/hooks/components), MobX-based presenters, RegisterFeature, and Admin BuildParams. Covers the admin/ directory structure for both features/ and presentation/ layers.

Building forms with the FormModel system — field types, renderers, layout, validation, conditional rules, computed fields, and dynamic zones. Use this skill when the developer needs to define form fields with the builder API, choose renderers, build layouts with tabs/rows/separators, add validation (Zod or imperative), use conditional visibility/disable rules, create computed fields, or work with object fields and templates (dynamic zones).

Covers the PreviewUrlModifier extension point in Website Builder. Use when a user wants to inject custom query parameters into live preview URLs — e.g. signed tokens, tenant identifiers, feature flags — from their Webiny project. Handles the full registration pattern: implementing the interface, wiring via createFeature + RegisterFeature, and registering via webiny.config.tsx. Supports async modifier methods (e.g. remote token fetch).

Covers how to configure the maximum allowed size of the Webiny API Lambda bundle using the Infra.Api.MaxBundleSize extension in webiny.config.tsx. Use when a project's API bundle exceeds the default 4.5 MB limit or when you want to enforce a stricter limit. Handles the extension syntax, byte calculations, and interpreting the build error message.

Migration patterns for converting v5 Webiny code to v6 architecture. Use this skill when migrating existing v5 plugins to v6 features, converting context plugins to DI services, adapting v5 event subscriptions to v6 EventHandlers, or understanding how v5 patterns translate to v6. Targeted at AI agents performing migrations.

Extending the Website Builder page settings with custom settings groups and modifiers. Use this skill when the developer wants to add a new tab/group to the page settings drawer (e.g., Publishing, Analytics, Access Control), or modify an existing settings group (e.g., add fields to General or SEO). Covers PageSettingsGroup, PageSettingsGroupModifier, and the doc.extensions data model. For field types, renderers, and layout details, see the webiny-form-model skill.

Use when writing or editing a @webiny/data-transfer config file (ddb.transfer.config.ts / os.transfer.config.ts / custom.transfer.config.ts). Covers createDdbConfig / createOsConfig signatures, credential shapes (fromAwsProfile vs literal), fromEnv / numberFromEnv helpers, loadEnv, source/target collision + trimming rules, pointing at a preset, tuning knobs.

Use when writing or editing a @webiny/data-transfer config file (config.ts). Covers createConfig signature, credential shapes (fromAwsProfile vs literal), fromEnv / numberFromEnv helpers, loadEnv, source/target collision + trimming rules, tuning knobs.

Use when writing or editing a @webiny/data-transfer preset file (the one referenced by pipeline.preset in a config). Covers createTransferPreset, pipelineBuilderFactory.create, filter/use/hook composition, first-match-wins record dispatch, unmatched-record drop semantics, writing transformers (createDdbTransformer / createOsTransformer), registering pipelines with the runner, and the onEnd auto-put behavior for DdbProcessor / OsProcessor.

Guided feature development for @webiny/stdlib using the DI abstraction → implementation → feature → index pattern. Use when adding a new tool, service, or feature to any slice (common, node, browser). Enforces TDD, file conventions, barrel exports, README creation, and the pre-commit chain. CRITICAL — existing tests must never be modified unless genuinely buggy.

Test-driven development with red-green-refactor loop. Use when user wants to build features or fix bugs using TDD, mentions "red-green-refactor", wants integration tests, or asks for test-first development.

Use when writing a new Webiny upgrade script for a specific version in the webiny-upgrades-v6 project.