- name
- edge-computing
- description
- Deep edge computing workflow—what runs at edge vs origin, caching, KV and data locality, security, limits, and latency validation. Use when deploying to CDN/edge workers (Cloudflare Workers, Lambda@Edge, Vercel Edge, etc.).
Edge Computing
Edge runtimes move logic closer to users—with strict CPU/time limits, different APIs than full Node, and tenant isolation requirements.
When to Offer This Workflow
Trigger conditions:
- Auth, redirects, or personalization at the CDN layer
- HTML rewriting, A/B assignment, or bot mitigation at the edge
- Global latency SLOs for read-heavy paths
Initial offer:
Use six stages: (1) workload fit, (2) edge vs origin split, (3) data & state, (4) security & tenancy, (5) limits & cost, (6) testing & rollout). Confirm platform (Workers, Lambda@Edge, Fastly Compute, etc.).
Stage 1: Workload Fit
Goal: Prefer short, CPU-light, request-scoped work—not long jobs or huge body buffering.
Exit condition: Explicit list of what remains on origin (heavy SSR, large uploads).
Stage 2: Edge vs Origin Split
Goal: Document what runs where: geo headers, redirects, cache key logic, A/B bucketing, partial HTML injection.
Practices
- Cache
Varyand cookie behavior documented to avoid wrong personalization leakage
Stage 3: Data & State
Goal: If using edge KV/Durable Objects/regional stores, state consistency (eventual vs strong) and rate of round-trips to origin.
Stage 4: Security & Tenancy
Goal: Validate JWT/session at edge; isolate tenants; never embed secrets in deploy bundles visible to clients.
Stage 5: Limits & Cost
Goal: Wall-clock CPU limits, request size caps, egress pricing; graceful degradation or fallback to origin.
Stage 6: Testing & Rollout
Goal: Canary per region/PoP; synthetics from multiple locations; compare p95 vs origin-only path.
Final Review Checklist
- [ ] Workload fits edge constraints
- [ ] Edge vs origin responsibilities documented
- [ ] State/consistency strategy clear
- [ ] Multi-tenant security reviewed
- [ ] Limits, cost, fallback documented
- [ ] Multi-region validation performed
Tips for Effective Guidance
- Edge runtimes differ from full Node—verify available APIs (fs, streams, crypto).
- Read platform-specific cold-start and isolate model docs.
Handling Deviations
- Hybrid: edge for headers/cache only; heavy compute stays on origin.