Sota Web Frameworks

SOTA Web Frameworks (2026)

Purpose

This skill encodes the 2026 state of the art for the two dominant JavaScript SSR stacks — React + Next.js and Vue + Nuxt — and the server-rendering concerns they share. It is deliberately framework-specific: the traps that matter here (the RSC server/client boundary, Server Actions as public endpoints, hydration mismatches, SSR state leaking across requests, runtimeConfig/NEXT_PUBLIC_ secret boundaries) do not exist at the plain-language level.

Two modes:

• BUILD — writing or modifying components, routes, and data-fetching to this standard.
• AUDIT — reviewing an existing app and reporting findings.

Read SKILL.md fully; load rules/*.md on demand per the index below. Verify every version/CVE claim at use time — this file's facts were primary-sourced 2026-07 but framework security moves weekly (see the 2025-12 React Server Components RCE).

Scope boundaries (what lives elsewhere)

This skill stacks on top of the general skills — load them together, don't duplicate:

• sota-javascript-typescript — strict tsconfig, type design, promises, Node hardening, npm supply chain. The language; this skill is the framework.
• sota-frontend-design — visual design, layout, components-as-UX, WCAG 2.2 accessibility, motion. This skill covers component engineering, not design.
• sota-code-security — generic XSS/CSRF/SSRF/authn/authz/crypto theory. This skill covers the framework-specific expression of those (RSC data exposure, Server Action authz, v-html, next/image SSRF).
• sota-performance rules/06 — Core Web Vitals, bundle budgets, image/font loading. This skill covers render-strategy choice (SSR/SSG/ISR/PPR) and hydration.
• sota-api-design — REST/GraphQL contract design for the routes themselves.

BUILD mode

1. Establish context first. Read package.json for the exact React/Next or Vue/Nuxt majors and the render mode in use (App vs Pages Router; Nuxt SSR vs ssr: false). Match the project's baseline — no Server Actions on a Pages-Router app, no defineModel below Vue 3.4. Confirm the versions are supported and patched against the CVE tables in rules/03/rules/05. (rules/01)
2. Default to the current idiom: React function components + hooks (let the React Compiler memoize — don't hand-write useMemo everywhere); Vue Composition API with <script setup>. Server Components by default in Next App Router, "use client" only at the leaves that need interactivity. (rules/02, rules/04)
3. The server/client boundary is a security boundary, not just a perf one. Every prop crossing server→client is serialized into the HTML/RSC payload and is public. Authorization lives next to the data (a Data Access Layer / validated server route), never only in middleware or a layout. (rules/03, rules/07)
4. Treat every Server Action and Nitro route as a public, unauthenticated HTTP endpoint until it validates input and checks authz itself — even if it looks internal or is never imported. (rules/03, rules/05, rules/07)
5. Get hydration right by construction: deterministic render (no Date.now(), Math.random(), or window in render), stable IDs via useId, SSR-safe shared state (useState/per-request instances, never module-level refs). (rules/06)
6. Serialize SSR state safely (framework serializer or escaped JSON, never naked JSON.stringify into <script>) and wire CSP (nonce or hash) knowing it forces dynamic rendering in Next. (rules/06, rules/07)
7. Tests accompany code (sota-testing): component tests plus at least one test that exercises the server/client boundary or a server route's authz.

AUDIT mode

1. Fingerprint + patch-check first. Pin exact framework/loader versions from the lockfile and diff them against the CVE tables in rules/03 and rules/05. An unpatched React2Shell (CVE-2025-55182) or middleware bypass (CVE-2025-29927) is CRITICAL on its own, before any code is read.
2. Trace the trust boundary. Grep "use client"/"use server", defineProps, runtimeConfig, NEXT_PUBLIC_/NUXT_PUBLIC_; find where server data crosses to the client and where authz is enforced. Middleware/layout-only authz is a finding.
3. Run each relevant rules file's Audit checklist (grep-driven), then read for design: hydration determinism, SSR state isolation, caching of personalized pages.
4. Verify every finding — a v-html fed a constant is not XSS; a Server Action that re-checks the session is not IDOR. Note mitigations already present.

Severity conventions

Finding format

file:line | rule violated (rules/NN §S) | severity | effort | fix

Effort: trivial · small · medium · large. Group by severity, CRITICAL first. Borderline severities state the deciding assumption; unconfirmed findings are marked "needs verification", never asserted. End with per-severity counts, the sweep commands run, and explicit "checked and clean" areas.

Rules index

Top-10 non-negotiables

1. Run supported, patched majors. React ≥ 19.x, Next ≥ 15.x (16.x current), Vue ≥ 3.5, Nuxt ≥ 4.x (Nuxt 3 security-only until 2026-07-31). Cross-check the CVE tables — an unpatched RSC RCE (CVE-2025-55182) or middleware bypass (CVE-2025-29927) is a ship-stopper. (rules/01, rules/03, rules/05)
2. Authorization lives next to the data, never only in middleware or a layout. proxy.ts/middleware is an optimization, not the auth layer; each Server Action, Route Handler, and Nitro route re-checks authn + authz. (rules/03, rules/07)
3. Every prop that crosses server→client is public. It's serialized into the RSC payload / HTML. Pass minimal DTOs, never raw DB rows, tokens, or process.env. (rules/03, rules/07)
4. Server Components by default; "use client" only where interactivity requires it. Keep secrets and data access in Server Components / server-only modules (import 'server-only'). (rules/02, rules/03)
5. Secrets never reach the client bundle. Nothing sensitive in NEXT_PUBLIC_*, VITE_*, or runtimeConfig.public — those are inlined at build time. (rules/07)
6. Validate every server-route/action input with a schema (getValidatedBody/Zod; never trust formData, searchParams, or headers), and check resource ownership to prevent IDOR. (rules/03, rules/05)
7. Hydrate deterministically: no Date/random/window in render, stable IDs via useId, SSR-safe shared state — and never "fix" a mismatch by injecting server-side user HTML. (rules/06)
8. Serialize SSR state safely. Framework serializer (devalue) or <-escaped JSON in <script>; naked JSON.stringify into a script tag is XSS. (rules/06)
9. User HTML is dangerous HTML. dangerouslySetInnerHTML/v-html only on sanitizer output; validate href/URL schemes (javascript:); lock next/image remotePatterns to explicit hosts (no **). (rules/02, rules/04, rules/07)
10. Don't cache personalized SSR at a shared cache. Cache-Control: private for per-user pages; know that CDNs drop Vary; wire CSP nonces knowing they force dynamic rendering. (rules/06)