A new approach to building composable software, from Cardstack.
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Skill Claude CodeCodex
Controlling child-card renders from the parent — fitted vs embedded format choice, the host-injected CardContainer chrome, and the plural-field/atom/stagger/divider traps. Use when embedding cards via or when an embedded/fitted child looks wrong (empty boxes, collapsed grids, double borders, invisible atoms).
Skill Claude CodeCodex
Fetch contexts — who carries auth where in Boxel (card code vs prerenderer vs CLI/orchestrator), and why raw fetch() from card code 401s on private realms. Use when card code needs to load cards, files, or external APIs, or when a fetch returns 401/unauthenticated data.
Skill Claude CodeCodex
Live, self-updating card lists via @context.searchResultsComponent — the SearchEntryWireQuery contract, query traps, clickable tiles, and live activity feeds. Use when a card needs to list other cards in the realm (home/dashboard sections, feeds, grids) or when a search section renders nothing.
Skill Claude CodeCodex
Map of everything Boxel card code can reach — base card-api, host tools, boxel-ui components/helpers, runtime-common, CardContext, AI services, BFM. Use when writing card code that needs an import you don't know the path for, or before reaching for raw fetch / a CDN / a hand-rolled capability.
Skill Claude CodeCodex needs its repo
Use when processing a bootstrap issue — covers how to create Project, IssueTracker, KnowledgeArticle, and implementation Issue cards from a brief.
Skill Claude CodeCodex
Lean V2 factory loop — design-first workflow, on-demand skills, no tests until hardening. Use when implementing cards in a target realm through the V2 factory execution loop.
Skill Claude CodeCodex
Use when working a software factory run from inside an interactive Claude Code session — picking the next unblocked Issue from a target realm, transitioning its status through the lifecycle, and recording progress as the agent works through the issue backlog. Replaces the orchestrator's issue-scheduler +…
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