c8y-architect-microservice-chassis-advisor

name	c8y-architect-microservice-chassis-advisor
description	Recommends the best Cumulocity microservice chassis / framework for a given project. Use when a developer or architect asks which microservice chassis to use, which framework to pick for a Cumulocity microservice, how to choose between NestJS, Nitro, Spring Boot, .NET, or Python for a microservice, or needs a chassis decision for TypeScript, JavaScript, Java, C#, or Python on Cumulocity.
argument-hint	Describe your project: team skills, expected load, use case, and any constraints (e.g. "Java team, enterprise ERP integration, high reliability required")

Cumulocity Microservice Chassis Advisor

When to Use

Invoke this skill whenever someone asks:

• "Which chassis / framework should I use for my Cumulocity microservice?"
• "Should I use NestJS, Spring Boot, .NET, or Python for my microservice?"
• "What is the best stack for a Cumulocity microservice?"
• "Help me choose between the available Cumulocity SDKs."
• Questions about trade-offs between NestJS, Nitro, Spring Boot, .NET Generic Host, or Python + FastAPI in the Cumulocity context.

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Procedure

Step 1 — Gather Requirements

Ask (or infer from context) the following. You do not need all answers; work with what is available.

#	Question	Why it matters
1	What is the primary use case? (e.g. ERP bridge, SCADA agent, data pipeline, platform extension, analytics)	Narrows the shortlist immediately
2	What is the team's primary tech stack? (TypeScript / Java / C# / Python / mixed)	Skill-fit is the strongest single factor
3	Is official Cumulocity SDK support a hard requirement?	Only Spring Boot + Java SDK is officially supported
4	What are the expected load characteristics? (low/bursty, medium/steady, high-throughput, mega-fleet)	Impacts runtime, footprint, and concurrency model
5	Are there resource / cost constraints on the deployment? (e.g. tight memory limits, edge deployment)	Favours Nitro or .NET AOT
6	Is AI / ML / data processing part of the microservice logic?	Strongly favours Python
7	Is this a rapid PoC or a long-lived production service?	PoC → Nitro or Python; production → NestJS, Spring Boot, or .NET
8	Are there enterprise governance requirements (e.g. auditability, support SLAs, supply-chain policies)?	Favours officially backed frameworks

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Step 2 — Evaluate Against the Decision Matrix

Score the shortlisted options against the criteria below.

Rating: 🟢 High / Excellent   |   🟡 Medium / Good   |   🔴 Low / Limited

Criterion	NestJS + @c8y/client	Nitro + c8y-nitro	Spring Boot + Java SDK	.NET Generic Host + C# SDK	Python + FastAPI
Team Skill Fit	🟢 Web / TS teams	🟢 Web / TS teams	🟡 Java specialists needed	🟡 .NET specialists needed	🟢 Broad — data, DevOps, web
Official Cumulocity Support	🟡 Community	🟡 Community	🟢 Official & fully supported	🟡 Community	🟡 Community
Cross-Cutting Features OOB	🟢 Comprehensive	🟢 Comprehensive	🟢 Comprehensive	🟢 Comprehensive	🟡 Moderate
Resilience Patterns OOB	🟡 Via libraries	🟡 Probes + libraries	🟢 Resilience4j native	🟢 Polly native	🟡 Via tenacity
Observability	🟡 Via plugins	🟢 Structured logging + OpenTelemetry	🟢 Actuator + Micrometer	🟢 OpenTelemetry native	🟡 Via libraries
Runtime Throughput & CPU Efficiency	🟡 Medium	🟢 High	🟡 Medium	🟢 High	🟡 Medium
Memory & Docker Image Footprint	🟡 Medium	🟢 Very Low	🔴 High (🟢 Low with Spring Boot AOT)	🟢 Low (🟢🟢 with AOT)	🟡 Medium
Cold Start / Startup Time	🟡 Fast	🟢 Very Fast	🔴 Slow (🟢 Very Fast with GraalVM)	🟡 Fast (🟢 Very Fast with AOT)	🟢 Fast
Scalability & Concurrency Model	🟢 Async event-loop	🟢 Async event-loop	🟡 Thread-pool (reactive opt.)	🟡 Thread-pool (async/await opt.)	🟡 Async via asyncio
Type Safety	🟢 Strong (TypeScript)	🟢 Strong (TypeScript)	🟢 Strong (Java)	🟢 Strong (C#)	🟡 Partial (type hints, Pydantic)
Boilerplate Required	🔴 Heavy	🟢🟢 None	🔴 Very Heavy	🔴 Heavy	🟢 Minimal
AI / ML & Data Integration	🟡 Via npm libraries	🟡 Via npm libraries	🟡 Via libraries (DL4J, Spring AI)	🟡 Via NuGet (ML.NET)	🟢 Native — NumPy, Pandas, PyTorch
Ecosystem Maturity & Community Size	🟢 Large	🟡 Nitro strong; c8y-nitro niche	🟢 Very Large	🟢 Large	🟢 Very Large
Long-term Commercial Backing	🟢 NestJS Inc.	🟢 Vercel-backed Nuxt/Nitro ecosystem	🟢 Broadcom (Spring)	🟢 Microsoft	🟢 PSF + broad industry

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Step 3 — Apply the Quick-Pick Rules

Use these rules to short-circuit the matrix for common scenarios:

If…	Recommend
Team is Java-based and official support is required	Spring Boot + Java SDK — only officially supported chassis
Team is TypeScript/Node and service will be long-lived, structured, and multi-protocol	NestJS + @c8y/client — strongest TS framework conventions and broad ecosystem for larger services
Service is resource-constrained, startup-sensitive, or needs fast iteration with strong C8Y batteries included	Nitro + c8y-nitro — very small footprint, very fast startup, and strong built-in Cumulocity ergonomics
Team is .NET/C# and throughput / image size matters	.NET Generic Host + C# SDK — especially strong with AOT compilation
Service involves AI/ML, data enrichment, or analytics	Python + FastAPI — unmatched data science ecosystem
Mixed team with no dominant skill and time-to-market pressure	NestJS (broad TypeScript adoption) or Python + FastAPI (low ramp-up)
Enterprise governance requires a supported SLA	Spring Boot + Java SDK — only option with official Cumulocity backing
Service involves complex business logic and heavy compute power for data analytics, image processing etc.	Spring Boot + Java SDK or .NET Generic Host + C# SDK — better suited for CPU-intensive workloads with enterprise-grade multi-threading
Service is I/O-heavy but not CPU-bound (e.g. API gateway, protocol translator)	Nitro + c8y-nitro — efficient async I/O with strong Cumulocity integration
Service handles and processes JSON-heavy data transformations	Nitro + c8y-nitro — efficient async I/O with strong Cumulocity integration
Service needs many enterprise integrations (databases, message queues, external APIs)	Spring Boot + Java SDK or .NET Generic Host + C# SDK — mature ecosystems with extensive integration libraries
Service needs fast development and deployment for a PoC or MVP	Nitro + c8y-nitro or Python + FastAPI — minimal boilerplate and fast iteration cycles

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Step 4 — Formulate a Recommendation

Structure your response as follows:

1. Primary recommendation — state the chassis and the top 2–3 reasons it fits the stated requirements.
2. Runner-up (if close) — one sentence on when to reconsider.
3. Trade-offs to watch — flag any 🔴 ratings on criteria that are important for this project.
4. Next steps — link to the relevant starter or documentation.

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Bundled Assets

Asset	When to load
references/dx.md	Use this if you want a detailed comparison of developer experience across different ecosystems

Resource Links

Chassis	Starter / Docs
NestJS + @c8y/client	NestJS · @c8y/client (npm) · Cumulocity Web SDK Docs
Nitro + c8y-nitro	Nitro · c8y-nitro (GitHub) · Starter Template
Spring Boot + Java SDK	Spring Boot · Java Microservice SDK (Docs) · Java Clients project · Maven Archetype for Microservice · Examples & Templates
.NET Generic Host + C# SDK	.NET · Cumulocity .NET SDK · Cumulocity .NET Client
Python + FastAPI	FastAPI · Python API (GitHub) · Python MS SDK (GitHub)