Amazon S3 Vectors vs. OpenSearch Serverless vs. pgvector for RAG: Cost Floors, Query Bills and Tenant Isolation

All three AWS vector stores can now cost close to nothing at rest, but they bill and isolate tenants in very different ways. This comparison models Amazon S3 Vectors, OpenSearch Serverless (classic and next generation) and Aurora PostgreSQL with pgvector across three workload shapes, checks the S3 Vectors model against the worked examples on the AWS pricing page, and shows where the tenant boundary belongs in each.

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Prompt Caching Economics on Amazon Bedrock and Azure OpenAI: Where It Pays and Where It Costs

Prompt caching cannot raise your bill on Azure OpenAI, but on Amazon Bedrock with Claude models a cache write costs more than not caching. This article derives the break-even points (one request per prefix every 20 minutes for the five-minute cache, every 80 minutes for the one-hour cache), gives a tested cost model, and shows how to measure cache read ratios on both platforms.

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Bedrock AgentCore Runtime vs. Lambda for Hosting Agents: Isolation, State and the Idle Bill

The same agent runs on AWS Lambda and on Amazon Bedrock AgentCore Runtime with two thin adapters. The differences are isolation, where conversation state lives and what is billed while the agent waits. AgentCore is cheaper for I/O-bound agents only if sessions are ended deliberately: left at defaults, idle memory makes it the more expensive option.

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One Abstraction, Two Clouds: Microsoft.Extensions.AI over Azure OpenAI and Amazon Bedrock

Microsoft.Extensions.AI gives .NET services one interface over Azure OpenAI and Amazon Bedrock. This article builds a two-provider ASP.NET Core service with per-provider telemetry, caching, token metering, tool calling and failover, and is clear about where the abstraction stops: model identity, errors, content safety and model behaviour remain provider-specific.

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Zero-Trust Microservice Networking: AWS VPC Lattice vs. Private API Gateway

In modern enterprise cloud architectures, applications rarely live in a single AWS Virtual Private Cloud (VPC) or even a single AWS account. Production environments are partitioned across dozens or hundreds of accounts for blast-radius isolation, compliance boundaries, and autonomous team ownership. However, securely interconnecting these distributed microservices has long been one of the most frustrating […]

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