# Migrate Swc Gen1 To Gen2 > Upgrade Spectrum 1 (sp-* elements, @spectrum-web-components/*) to Spectrum 2 (swc-* elements, @adobe/spectrum-wc). Use when developers need to migrate from Spectrum 1 to Spectrum 2 web components, or when they mention @spectrum-web-components, sp-* elements, or Spectrum 1. - Skill: `adobe/migrate-swc-gen1-to-gen2` (Agent Skill) - Install (CLI): `npx skillmds@latest add adobe/migrate-swc-gen1-to-gen2` - Raw SKILL.md: https://api.skillmd.com/api/skills/adobe/migrate-swc-gen1-to-gen2/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Coding & Dev Tools - License: Apache-2.0 - Author: Adobe (https://skillmd.com/u/adobe) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/adobe/migrate-swc-gen1-to-gen2 --- # Spectrum 1 → Spectrum 2 migration Upgrade `sp-*` Spectrum 1 components (`@spectrum-web-components/*`) to `swc-*` Spectrum 2 components (`@adobe/spectrum-wc`). **You do not have to migrate everything at once.** Gen 1 and Gen 2 coexist in the same app — `` and `` are independent custom elements. Migrate one component (or one screen) at a time. ## TL;DR 1. Install `@adobe/spectrum-wc` alongside your existing `@spectrum-web-components/*` packages. 2. Switch Gen 1 to the `spectrum-two` theme so it aligns visually with Gen 2. 3. Add the Gen 2 stylesheet and `swc-theme` classes to your application root. 4. Load Adobe Clean Spectrum VF (the Spectrum 2 font). 5. Replace `` elements with `` one component at a time, following each component's migration guide. 6. Once no `` elements remain, remove Gen 1 packages, theme imports, and ``. For the full coexistence walkthrough — including font setup, `--mod-*` → `--swc-*` CSS mapping, and decommissioning Gen 1 — read [Migrate from Gen1](references/guides/migrate-from-gen1.md) first. ## Scope This skill covers the Spectrum 1 → Spectrum 2 migration only. Do **not** perform major framework upgrades (e.g. React version bumps) as part of this migration; note them as recommended follow-ups in the final report instead. ## Step 1 — Read the overarching migration guide Before starting, read [Migrate from Gen1](references/guides/migrate-from-gen1.md). It covers the coexistence model, theme bridging, font loading, CSS namespace changes, and decommissioning. Understanding this context prevents common mistakes. ## Step 2 — Identify what is being migrated - Search package manifests for `@spectrum-web-components/*` dependencies. - Note the package manager (npm / yarn / pnpm) from the lockfile. - Find app entrypoints, root providers, and any `` usages. - Check each `sp-*` component against the list of available migration guides below. Components without a guide are still Gen 1 only — keep them installed. ## Step 3 — Install Gen 2 ```bash npm install @adobe/spectrum-wc yarn add @adobe/spectrum-wc pnpm add @adobe/spectrum-wc ``` Keep existing `@spectrum-web-components/*` packages. Gen 2 ships as a single monorepo package; import individual components from subpaths. ## Step 4 — Align Gen 1 visually with Spectrum 2 Switch the existing `` to `system="spectrum-two"` to keep Gen 1 components visually consistent with their `` neighbors: ```ts import '@spectrum-web-components/theme/sp-theme.js'; import '@spectrum-web-components/theme/src/spectrum-two/themes.js'; ``` ```html ``` ## Step 5 — Add the Gen 2 stylesheet and theme classes ```ts // App entry — import once import '@adobe/spectrum-wc/swc.css'; ``` ```html ``` Theme classes: `swc-theme--light`, `swc-theme--dark`, `swc-theme--adaptive`. See [Theme and scales](references/guides/customization-theme-scales.md). ## Step 6 — Load Adobe Clean Spectrum VF Gen 2 uses Adobe Clean Spectrum VF (the Spectrum 2 font family). See [Fonts](references/guides/customization-fonts.md) for Adobe Fonts, CDN, and self-hosted setup instructions. ## Step 7 — Replace components one at a time For each component to migrate: 1. Open the component's migration guide from `references/components/` (e.g. `references/components/badge.md`). It lists renamed attributes, removed features, new additions, and a CSS custom property mapping table. 2. Update the import: ```ts // Before import '@spectrum-web-components/badge/sp-badge.js'; // After import '@adobe/spectrum-wc/components/badge/swc-badge.js'; ``` 3. Rename the tag (`` → ``) and apply attribute renames. 4. Replace `--mod-badge-*` CSS overrides with `--swc-badge-*` equivalents. See [Component styles](references/guides/customization-component-styles.md). The tag prefix always changes from `sp-` to `swc-` across all components. ## Step 8 — Validate 1. Type-check: `tsc --noEmit` 2. Run tests covering the migrated components. 3. Run the build and verify output. Fix all failures before declaring the migration complete. ## Step 9 — Decommission Gen 1 (when ready) Once no `` elements remain: 1. Remove `@spectrum-web-components/*` from `package.json`. 2. Remove `` and its imports. 3. Remove remaining `--mod-*` CSS overrides. ## Step 10 — Generate final report Summarise: **Changes made** - Packages added and removed - Components migrated (before/after tag names) - Attributes renamed or removed - CSS custom property renames applied **Remaining items** - Components with no Gen 2 equivalent yet (still on Gen 1) - Any open questions or gaps **Recommended follow-ups** - Any major dependency upgrades that were out of scope ## Documentation structure ### Overarching guides {{MIGRATION_GUIDE_LIST}} ### Per-component migration guides One file per migrated component in `references/components/`. Read the guide for a component to see its exact breaking changes and CSS mapping. Components with a migration guide: {{MIGRATION_COMPONENT_NAMES}}. Components **without** a migration guide are still Gen 1 only. Keep `@spectrum-web-components/[name]` installed until a Gen 2 equivalent ships. {{MIGRATION_COMPONENT_LIST}}