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Can an AWS VPC Have Two Peering Connections? Yes. But Should It?

When teams begin structuring cloud networks in AWS, one of the first connectivity mechanisms they encounter is VPC Peering. It is simple, direct, and usually easy to implement for small environments. A common question appears quickly: Can a VPC have two peering connections? The answer is straightforward: yes, it can. A single VPC can maintain
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Sending Events to Multiple PostHog Projects from the Same Website

In some architectures, a single website needs to send analytics events to multiple PostHog projects. This situation commonly appears in the following scenarios: PostHog supports this setup by allowing multiple instances of the JavaScript SDK to run simultaneously on the same website. How Multiple PostHog Instances Work PostHog allows initializing multiple instances of the SDK
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Lambda vs n8n: A Simple Explanation for Data Workflows

Introduction When building data systems or integrating APIs, a common question appears: should we use AWS Lambda or n8n? Both tools can automate processes, call APIs, and move data between systems, but they are not the same thing and should not be used for the same purpose. The simplest way to understand the difference is
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Should You Use AWS Lambda or AWS Glue to Update Records in HubSpot?

When integrating HubSpot with a data platform on AWS, a common architectural decision appears quickly: Should updates to HubSpot be executed from AWS Lambda or AWS Glue?The correct choice depends on workload characteristics, latency requirements, and system design principles. This article explains the decision from an architectural and data engineering perspective. The Nature of the
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Understanding client_ingestion_warning in PostHog: Are You Losing Data?

When using PostHog with the default posthog-js configuration, you may encounter the following warning: In the UI, this appears as: This article explains what it means, why it happens, and whether you are losing data. What Is client_ingestion_warning? client_ingestion_warning is an internal warning emitted by the PostHog JavaScript SDK when the client-side rate limiter is
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Hardening OAuth Token Management in Postman: Preventing Environment Cross-Contamination

When working with multiple third-party APIs (Zoom, HubSpot, Meta, etc.), a common operational risk in Postman is environment cross-contamination. Tokens may be overwritten unintentionally if the wrong environment is active. This article describes a controlled, production-grade approach to managing OAuth tokens safely in Postman. The Core Problem If all environments share a variable named: and
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Daily Failure Reporting in DynamoDB Using Lambda, EventBridge Scheduler, and SES

Operational monitoring requires structured visibility into failures. If your processes write execution logs to DynamoDB and mark failed executions with status = FAILED, you can implement a deterministic daily reporting pipeline using AWS Lambda, EventBridge Scheduler, and Amazon SES. This article describes a single, production-grade implementation. Objective Architecture This solution is fully serverless and horizontally
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Understanding ip-api Batch Limits and Effective Throughput

When integrating IP geolocation into a data pipeline, understanding rate limits and batching constraints is essential. This post analyzes the practical limits of the ip-api free tier and how to compute effective throughput. 1. Free Tier Constraints The ip-api free plan imposes the following restrictions: These limits apply globally per source IP address. 2. Maximum
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Window Functions vs JOIN in Spark: A Physical Plan Perspective

When solving analytical queries in Spark SQL, there are often multiple correct formulations. However, they do not produce equivalent execution plans. This article compares two approaches to the same problem: “Find the second highest salary per department, but only in departments with at least two employees.” We analyze which approach is more efficient and why,
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