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Software Letters

Sharing insights about Software engineering, Design patterns, AI applications and NoCode tools.

Written by

Houssem BEN SLAMA

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Featured Posts

SQS

SL#39 - Make Your Serverless Stack Observable—Before It Breaks

Oct 15, 2025

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4 min read

SL#39 - Make Your Serverless Stack Observable—Before It Breaks

Tracing async workflows, debugging across queues, and the metrics that actually matter—an advanced guide for serverless teams.

Houssem BEN SLAMA

AWS

SL#35 - Building a Serverless ETL Pipeline with AWS Glue: Integrating DynamoDB, S3, and OpenSearch

Aug 3, 2025

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7 min read

SL#35 - Building a Serverless ETL Pipeline with AWS Glue: Integrating DynamoDB, S3, and OpenSearch

AWS Glue is a fully managed ETL (Extract, Transform, Load) service designed to simplify data integration. It automates much of the effort in building, maintaining, and running ETL jobs by providing a serverless environment, built-in transformation logic, and native integration with other AWS services like S3, DynamoDB, and OpenSearch.

Houssem BEN SLAMA

DDD

SL#33 - Understanding the C4 Architecture Model: A Detailed Breakdown

Oct 3, 2024

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12 min read

SL#33 - Understanding the C4 Architecture Model: A Detailed Breakdown

Adapting the C4 Model for Serverless, Domain-Driven Design (DDD), and Event-Driven Architecture (EDA)

Houssem BEN SLAMA

Data-lake

SL#19 - Unleashing the Power of Real-Time Data: A Comprehensive Guide to Apache Kafka

Jul 2, 2024

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9 min read

SL#19 - Unleashing the Power of Real-Time Data: A Comprehensive Guide to Apache Kafka

Understanding Apache Kafka’s Architecture, Benefits, and How It Outperforms Other Data Platforms

Houssem BEN SLAMA

Kubernetes

Jun 5, 2024

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10 min read

SL#15 - Essential kubectl Commands: The Top 100 You Must Know for Effective Kubernetes Management

From Basic Operations to Advanced Techniques

Houssem BEN SLAMA

Containerization

SL#14 - Kubernetes and Docker: Revolutionizing Container Orchestration

Jun 4, 2024

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9 min read

SL#14 - Kubernetes and Docker: Revolutionizing Container Orchestration

Unleashing the Power of Containerization and Orchestration for Modern Applications

Houssem BEN SLAMA

SL#57 - AWS AI Series (1/30) - One API, Two Model Families: Build a Bedrock CLI with Converse, Streaming, and Validated JSON

Episode 1 of the AWS AI Series: a Python CLI that talks to Amazon Nova 2 and Claude Sonnet 4.6 through one identical code path, streams tokens, and returns schema-validated JSON. About an hour, end to end.

Houssem BEN SLAMA

DevOps

SL#56 - All Three Availability Zones Failed Together. Twice in Five Weeks.

Jun 3, 2026

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7 min read

SL#56 - All Three Availability Zones Failed Together. Twice in Five Weeks.

Multi-AZ is sold as protection against correlated failure. Two Azure incidents this spring show the independence assumption only ever covered one peril, and that your stateful layer never recovers at the speed of your compute.

Houssem BEN SLAMA

Software Engineering

SL#55 - GitHub Just Shipped Stacked PRs. They Fix the Wrong Half of Code Review.

May 30, 2026

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6 min read

SL#55 - GitHub Just Shipped Stacked PRs. They Fix the Wrong Half of Code Review.

Splitting a 2,000-line diff into five 400-line PRs makes each one easier to read. It does nothing about the only resource code review actually runs out of: a reviewer who is paying attention.

Houssem BEN SLAMA

AI Agents

SL#54 - Your 12-Million-Token Context Window Is a Lie Until You Measure It

May 27, 2026

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7 min read

SL#54 - Your 12-Million-Token Context Window Is a Lie Until You Measure It

SubQ shipped a frontier-class subquadratic LLM with a 12M-token window and benchmarks that beat Opus 4.6. The interesting story isn't the architecture. It's what their own numbers reveal about the gap between context size and context use.

Houssem BEN SLAMA

Tutorial

SL#53 - Cut Your Lambda Cold Starts from 6 Seconds to 780ms with SnapStart and Priming

May 25, 2026

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7 min read

SL#53 - Cut Your Lambda Cold Starts from 6 Seconds to 780ms with SnapStart and Priming

We'll build a SnapStart-enabled Java Lambda with CRaC priming hooks, deploy it with AWS SAM, and benchmark the p99.9 cold start down from 6.2s to 781ms. Plan for 90 minutes if you have written a Lambda in Java before.

Houssem BEN SLAMA

Software Engineering

SL#52 - The Debt AI Is Building Isn't In Your Code

May 24, 2026

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6 min read

SL#52 - The Debt AI Is Building Isn't In Your Code

Refactoring used to be the antidote to messy code. It can't reach the kind of debt your team is now accumulating, because the debt has moved somewhere refactoring can't go.

Houssem BEN SLAMA

AI Agents

SL#51 - Your Coding Agent Didn't Solve SWE-bench. It Cheated.

May 22, 2026

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6 min read

SL#51 - Your Coding Agent Didn't Solve SWE-bench. It Cheated.

A team at Berkeley built a scanner that scored near-perfect on eight of the most-cited AI agent benchmarks without solving a single task. The leaderboard you used to pick your model is measuring the wrong thing.

Houssem BEN SLAMA

Tutorial

SL#50 - Build a Claude Sub-Agent That Reviews Your PRs Against a Team Style Guide

May 21, 2026

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7 min read

SL#50 - Build a Claude Sub-Agent That Reviews Your PRs Against a Team Style Guide

A 200-line TypeScript build using the Claude Agent SDK. The non-obvious bit: one sub-agent per file beats one big prompt, and it costs less. Plan for 90 minutes if you have used the Agent SDK before, 3 hours if this is your first time.

Houssem BEN SLAMA

DevOps

SL#49 - The Eight-Hour Outage After a Seven-Minute Fix

May 21, 2026

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6 min read

SL#49 - The Eight-Hour Outage After a Seven-Minute Fix

Railway's Google Cloud account was suspended at 22:20 UTC and reinstated at 22:29. The platform was still down at 06:14 the next morning. The lesson is bigger than Railway.

Houssem BEN SLAMA

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Featured Posts

SL#39 - Make Your Serverless Stack Observable—Before It Breaks

SL#35 - Building a Serverless ETL Pipeline with AWS Glue: Integrating DynamoDB, S3, and OpenSearch

SL#33 - Understanding the C4 Architecture Model: A Detailed Breakdown

SL#19 - Unleashing the Power of Real-Time Data: A Comprehensive Guide to Apache Kafka

SL#15 - Essential kubectl Commands: The Top 100 You Must Know for Effective Kubernetes Management

SL#14 - Kubernetes and Docker: Revolutionizing Container Orchestration

Archive

SL#57 - AWS AI Series (1/30) - One API, Two Model Families: Build a Bedrock CLI with Converse, Streaming, and Validated JSON

SL#56 - All Three Availability Zones Failed Together. Twice in Five Weeks.

SL#55 - GitHub Just Shipped Stacked PRs. They Fix the Wrong Half of Code Review.

SL#54 - Your 12-Million-Token Context Window Is a Lie Until You Measure It

SL#53 - Cut Your Lambda Cold Starts from 6 Seconds to 780ms with SnapStart and Priming

SL#52 - The Debt AI Is Building Isn't In Your Code

SL#51 - Your Coding Agent Didn't Solve SWE-bench. It Cheated.

SL#50 - Build a Claude Sub-Agent That Reviews Your PRs Against a Team Style Guide

SL#49 - The Eight-Hour Outage After a Seven-Minute Fix

Software Letters