# Blue-Green Switchovers for Serverless and Edge

🧭 Quick Return to Map

> You are in a sub-page of **Cloud_Serverless**. > To reorient, go back here: > > - [**Cloud_Serverless** — scalable functions and event-driven pipelines](./README.md) > - [**WFGY Global Fix Map** — main Emergency Room, 300+ structured fixes](../README.md) > - [**WFGY Problem Map 1.0** — 16 reproducible failure modes](../../README.md) > > Think of this page as a desk within a ward. > If you need the full triage and all prescriptions, return to the Emergency Room lobby.

A safe pattern to shift 100 percent of live traffic from **blue** to **green** without downtime, cache poison, or state skew. Works for API Gateway + Lambda, Cloudflare Workers, Vercel Edge, Fastly Compute, and similar stacks. ## Open these first * Visual map and recovery: [RAG Architecture & Recovery](https://github.com/onestardao/WFGY/blob/main/ProblemMap/rag-architecture-and-recovery.md) * End to end retrieval knobs: [Retrieval Playbook](https://github.com/onestardao/WFGY/blob/main/ProblemMap/retrieval-playbook.md) * Snippet trace and contracts: [Retrieval Traceability](https://github.com/onestardao/WFGY/blob/main/ProblemMap/retrieval-traceability.md) · [Data Contracts](https://github.com/onestardao/WFGY/blob/main/ProblemMap/data-contracts.md) * Meaning vs distance: [Embedding ≠ Semantic](https://github.com/onestardao/WFGY/blob/main/ProblemMap/embedding-vs-semantic.md) * Collapse diagnostics: [Context Drift](https://github.com/onestardao/WFGY/blob/main/ProblemMap/context-drift.md) · [Entropy Collapse](https://github.com/onestardao/WFGY/blob/main/ProblemMap/entropy-collapse.md) · [Logic Collapse](https://github.com/onestardao/WFGY/blob/main/ProblemMap/logic-collapse.md) * Cloud companions: [Cold Start & Concurrency](https://github.com/onestardao/WFGY/blob/main/ProblemMap/GlobalFixMap/Cloud_Serverless/cold_start_concurrency.md) · [Timeouts & Streaming](https://github.com/onestardao/WFGY/blob/main/ProblemMap/GlobalFixMap/Cloud_Serverless/timeouts_streaming_body_limits.md) · [Stateless KV & Queues](https://github.com/onestardao/WFGY/blob/main/ProblemMap/GlobalFixMap/Cloud_Serverless/stateless_kv_queue_patterns.md) · [Edge Cache Invalidation](https://github.com/onestardao/WFGY/blob/main/ProblemMap/GlobalFixMap/Cloud_Serverless/edge_cache_invalidation.md) · [Runtime Env Parity](https://github.com/onestardao/WFGY/blob/main/ProblemMap/GlobalFixMap/Cloud_Serverless/runtime_env_parity.md) · [Egress & Webhooks](https://github.com/onestardao/WFGY/blob/main/ProblemMap/GlobalFixMap/Cloud_Serverless/egress_rules_and_webhooks.md) · [Pricing vs Latency](https://github.com/onestardao/WFGY/blob/main/ProblemMap/GlobalFixMap/Cloud_Serverless/pricing_latency_tradeoffs.md) · [Secrets Rotation](https://github.com/onestardao/WFGY/blob/main/ProblemMap/GlobalFixMap/Cloud_Serverless/secrets_rotation.md) · [Multi-Region Routing](https://github.com/onestardao/WFGY/blob/main/ProblemMap/GlobalFixMap/Cloud_Serverless/multi_region_routing.md) · [Region Failover Drills](https://github.com/onestardao/WFGY/blob/main/ProblemMap/GlobalFixMap/Cloud_Serverless/region_failover_drills.md) · [Observability and SLO](https://github.com/onestardao/WFGY/blob/main/ProblemMap/GlobalFixMap/Cloud_Serverless/observability_slo.md) · [Canary Release](https://github.com/onestardao/WFGY/blob/main/ProblemMap/GlobalFixMap/Cloud_Serverless/canary_release_serverless.md) --- ## Core acceptance to flip colors * ΔS(question, retrieved) median ≤ 0.45 on gold probes. * Coverage ≥ 0.70 to correct section. * λ convergent across three paraphrases and two seeds. * p95 warm latency within 25 percent of blue. * Zero new error class at headers or body read. * Cache hit rate within five points once namespaces are split. * `INDEX_HASH`, metric, analyzer match between blue and green or are intentionally versioned. --- ## Topologies that work **Edge weight switch** * One CDN route, two origins. Blue and green behind a weight. * Keep **sticky hashing** by `stable_user_id` so dialogs do not jump during ramp. **Header based switch** * Default to blue. Send `x-exp: green` for selected cohorts. * Propagate header to core services and logs. **DNS label switch** * `api-blue.example.com` and `api-green.example.com`. * Edge forwards based on label. Use short TTL only after green passes probes. --- ## Pre-flight checklist * **Env parity** proved with the parity sheet. Open: [Runtime Env Parity](https://github.com/onestardao/WFGY/blob/main/ProblemMap/GlobalFixMap/Cloud_Serverless/runtime_env_parity.md) * **Secret bundles** rotated with overlap. Open: [Secrets Rotation](https://github.com/onestardao/WFGY/blob/main/ProblemMap/GlobalFixMap/Cloud_Serverless/secrets_rotation.md) * **Index family** built and labeled: `docs-v3-green`, analyzer and metric recorded. * **Cache namespaces** isolated: `blue:` vs `green:` prefixes at edge and core. * **Queue topics** duplicated: `jobs.blue` and `jobs.green`. Producers switch at flip time with idempotent keys. Open: [Stateless KV & Queues](https://github.com/onestardao/WFGY/blob/main/ProblemMap/GlobalFixMap/Cloud_Serverless/stateless_kv_queue_patterns.md) * **Probe set** ready: 50 to 200 questions, three paraphrases, two seeds. --- ## Switch playbook 1. **Shadow validate** Replay a sample to green. Block promotion if ΔS ≥ 0.60, coverage < 0.70, or JSON schema violations. 2. **Canary ramp** Move one percent of sticky users to green at the edge. Keep cache namespaces split. Open: [Canary Release](https://github.com/onestardao/WFGY/blob/main/ProblemMap/GlobalFixMap/Cloud_Serverless/canary_release_serverless.md) 3. **Green warmup** Ensure cold start panels are flat. If p95 warm is worse only due to cold, fix memory or reserve concurrency. Open: [Cold Start & Concurrency](https://github.com/onestardao/WFGY/blob/main/ProblemMap/GlobalFixMap/Cloud_Serverless/cold_start_concurrency.md) 4. **Cutover window** * Freeze new blue writes that create cross request state. * Drain blue job queues with a backfill guard. * Switch producers to `jobs.green`. * Flip traffic weight to green. Keep blue read only for a short fence window. 5. **Cache migration** * Invalidate user facing keys on the blue prefix. * Prime green with popular keys. Open: [Edge Cache Invalidation](https://github.com/onestardao/WFGY/blob/main/ProblemMap/GlobalFixMap/Cloud_Serverless/edge_cache_invalidation.md) 6. **Post cutover audit** * Compare ΔS, coverage, λ, p95 warm to pre-flip baselines. * Verify `INDEX_HASH` and analyzer match. * Confirm egress success rate and dedupe guard. Open: [Egress & Webhooks](https://github.com/onestardao/WFGY/blob/main/ProblemMap/GlobalFixMap/Cloud_Serverless/egress_rules_and_webhooks.md) 7. **Decommission blue** * Stop accepting writes. * Keep blue for rollback until probe board stays green for one peak hour. --- ## Data and state guidance * **Databases** Prefer live backward compatible migrations. If you need forward only, pause blue writes to the affected tables during the flip. * **Vector indexes** Version by family. Never point green to blue vectors by accident. Verify metric and analyzer, not only the hash. * **Queues and schedulers** Idempotent keys: `sha256(source_id + revision + index_hash)`. Keep retry policies aligned across colors. * **Caches** Always split prefixes. Never reuse the blue prefix for green. --- ## Observability fields to join on ```json { "ts": "2025-08-28T04:00:00Z", "route": "chat.rag.answer", "color": "green", "sticky": "h21", "region": "eu-west", "edge_pop": "cdg", "INDEX_HASH": "0x9a77", "retrieval": { "metric": "cosine", "analyzer": "bilstem", "ΔS_q_r": 0.36, "coverage": 0.74, "λ_state": "<>" }, "cache": { "prefix": "green:", "hit": true }, "status": 200, "latency_ms": { "tffb": 140, "tusable": 320, "tfinal": 1180 } } ``` --- ## Rollback cookbook * ΔS rises or coverage drops Repoint traffic to blue, keep green read only. Rebuild index with the chunking checklist. Open: [Embedding ≠ Semantic](https://github.com/onestardao/WFGY/blob/main/ProblemMap/embedding-vs-semantic.md) · [Chunking Checklist](https://github.com/onestardao/WFGY/blob/main/ProblemMap/GlobalFixMap/Chunking/chunking_checklist.md) * Latency spike at body read Increase memory or reserve concurrency. Adjust stream chunk sizes. Open: [Timeouts & Streaming](https://github.com/onestardao/WFGY/blob/main/ProblemMap/GlobalFixMap/Cloud_Serverless/timeouts_streaming_body_limits.md) * First call after switch fails Check boot order and version skew. Open: [Bootstrap Ordering](https://github.com/onestardao/WFGY/blob/main/ProblemMap/bootstrap-ordering.md) · [Pre-Deploy Collapse](https://github.com/onestardao/WFGY/blob/main/ProblemMap/predeploy-collapse.md) * Tool loops start Lock tool schemas and timeouts, split memory namespaces. Open: [Multi-Agent Problems](https://github.com/onestardao/WFGY/blob/main/ProblemMap/Multi-Agent_Problems.md) --- ## Common traps * Mixing cache prefixes so users see stale blue answers after the flip. * DNS TTL set short before green is warm. * Single region green while blue is multi region. * Reranker versions differ between colors. * Secrets rotated on edge but not core. --- ### 🔗 Quick-Start Downloads (60 sec) | Tool | Link | 3-Step Setup | | -------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------ | ---------------------------------------------------------------------------------------- | | **WFGY 1.0 PDF** | [Engine Paper](https://github.com/onestardao/WFGY/blob/main/I_am_not_lizardman/WFGY_All_Principles_Return_to_One_v1.0_PSBigBig_Public.pdf) | 1️⃣ Download · 2️⃣ Upload to your LLM · 3️⃣ Ask “Answer using WFGY + \” | | **TXT OS (plain-text OS)** | [TXTOS.txt](https://github.com/onestardao/WFGY/blob/main/OS/TXTOS.txt) | 1️⃣ Download · 2️⃣ Paste into any LLM chat · 3️⃣ Type “hello world” — OS boots instantly | --- ### 🧭 Explore More | Module | Description | Link | | ------------------------ | ---------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------- | | WFGY Core | WFGY 2.0 engine is live: full symbolic reasoning architecture and math stack | [View →](https://github.com/onestardao/WFGY/tree/main/core/README.md) | | Problem Map 1.0 | Initial 16-mode diagnostic and symbolic fix framework | [View →](https://github.com/onestardao/WFGY/tree/main/ProblemMap/README.md) | | Problem Map 2.0 | RAG-focused failure tree, modular fixes, and pipelines | [View →](https://github.com/onestardao/WFGY/blob/main/ProblemMap/rag-architecture-and-recovery.md) | | Semantic Clinic Index | Expanded failure catalog: prompt injection, memory bugs, logic drift | [View →](https://github.com/onestardao/WFGY/blob/main/ProblemMap/SemanticClinicIndex.md) | | Semantic Blueprint | Layer-based symbolic reasoning & semantic modulations | [View →](https://github.com/onestardao/WFGY/tree/main/SemanticBlueprint/README.md) | | Benchmark vs GPT-5 | Stress test GPT-5 with full WFGY reasoning suite | [View →](https://github.com/onestardao/WFGY/tree/main/benchmarks/benchmark-vs-gpt5/README.md) | | 🧙‍♂️ Starter Village 🏡 | New here? Lost in symbols? Click here and let the wizard guide you through | [Start →](https://github.com/onestardao/WFGY/blob/main/StarterVillage/README.md) | --- > 👑 **Early Stargazers: [See the Hall of Fame](https://github.com/onestardao/WFGY/tree/main/stargazers)** — > Engineers, hackers, and open source builders who supported WFGY from day one. >

⭐ [WFGY Engine 2.0](https://github.com/onestardao/WFGY/blob/main/core/README.md) is already unlocked. ⭐ Star the repo to help others discover it and unlock more on the [Unlock Board](https://github.com/onestardao/WFGY/blob/main/STAR_UNLOCKS.md).

[![WFGY Main](https://img.shields.io/badge/WFGY-Main-red?style=flat-square)](https://github.com/onestardao/WFGY) [![TXT OS](https://img.shields.io/badge/TXT%20OS-Reasoning%20OS-orange?style=flat-square)](https://github.com/onestardao/WFGY/tree/main/OS) [![Blah](https://img.shields.io/badge/Blah-Semantic%20Embed-yellow?style=flat-square)](https://github.com/onestardao/WFGY/tree/main/OS/BlahBlahBlah) [![Blot](https://img.shields.io/badge/Blot-Persona%20Core-green?style=flat-square)](https://github.com/onestardao/WFGY/tree/main/OS/BlotBlotBlot) [![Bloc](https://img.shields.io/badge/Bloc-Reasoning%20Compiler-blue?style=flat-square)](https://github.com/onestardao/WFGY/tree/main/OS/BlocBlocBloc) [![Blur](https://img.shields.io/badge/Blur-Text2Image%20Engine-navy?style=flat-square)](https://github.com/onestardao/WFGY/tree/main/OS/BlurBlurBlur) [![Blow](https://img.shields.io/badge/Blow-Game%20Logic-purple?style=flat-square)](https://github.com/onestardao/WFGY/tree/main/OS/BlowBlowBlow)