Understanding the behavior of Terraform's one() function. Introduction Understanding the Behavior of one() Specification of one() Examples When to Use one() Conclusion References Introduction Terraform provides a one() function. Because th…

This post explains how to output a resource in Terraform when its creation is controlled using the count parameter. Introduction Outputting Resources Controlled by count Method 1: Use the one Function Method 2: Use the try Function Conclus…

Here's a quick memo on converting webp to png/jpeg with the ffmpeg command. Introduction Convert WebP to PNG or JPEG Using ffmpeg How to Do It Try It Conclusion References Introduction Sometimes you need to convert images in WebP format to…

This post summarizes how to perform AssumeRole using Boto3. Introduction Assuming Roles with Boto3 Implementing the AssumeRole function Example Usage Conclusion References Introduction There are many situations where you need to AssumeRole…

This post introduces a convenient way to automate git commit using a custom slash command in Claude Code. Introduction Auto-Commit with a Custom Slash Command in Claude Code How to Do It Example Conclusion References Introduction Writing a…

This post is a quick memo on how to create custom slash commands in Claude Code. Introduction What Are Custom Slash Commands in Claude Code? How to Create Custom Slash Commands Basic Syntax and Example Commands Prompt Only Arguments Runnin…

This is a quick memo on how to bulk delete all your chat history in Claude. Introduction How to Bulk Delete All Chats in Claude Steps Example Conclusion References Introduction Lately, I've been using Claude more often than ChatGPT. I coul…

This post summarizes how to get the exit status from commands in a pipeline. Introduction How to Get Exit Statuses from a Pipeline Using PIPESTATUS Using set -o pipefail Conclusion References Introduction When you try to get the exit statu…

This post explains the CloudFormation template that sets up the backend (S3/DynamoDB) to store Terraform state. Introduction CloudFormation Template to Provision Terraform Backend Conclusion References Introduction How to provision the bac…

This is a quick note on how to output DEBUG-level logs using the AWS CLI. Introduction Outputting DEBUG-Level Logs with AWS CLI How to do it Example Execution Conclusion References Introduction There are times when you want to run AWS CLI …

This is a quick memo on how to retrieve all AWS service names (subcommands) provided via AWS CLI. Introduction How to List All Available Services in AWS CLI Method Example Conclusion References Introduction Sometimes you might want to list…

How to fix the issue where searching with grep the output of aws help doesn't work as expected? Introduction Why You Can't Grep AWS CLI Help Output Cause Solution Example Conclusion References Introduction When you try to grep or use sed o…

If you delete the chat where the image was generated, the corresponding image will also be deleted from the ChatGPT Library. Introduction How to Delete Images from ChatGPT Library Method Let’s Try It Conclusion Reference Introduction A new…

In this post, I’ll run a simple robot experiment on Raspberry Pi, combining a camera and servo motors with GPT-4 Vision. For Part 1, see: en.bioerrorlog.work Introduction Combining GPT-4 Vision with Raspberry Pi Concept Setup Hardware Soft…

We'll conduct a simple experiment combining a camera, servo motors, and GPT on a Raspberry Pi. Introduction Combining GPT with Raspberry Pi, Camera, and Servo Motors Prototype Concept Setup Hardware Software Results Challenges Object Detec…

We will create a shell command to quickly combine the contents of multiple files, including directory structure information, for LLM prompts. Introduction Shell Command to Concatenate Multiple Files for AI Coding Goal Command Implementatio…

This is a quick note on how to control multiple servo motors using only the GPIO pins on a Raspberry Pi—without relying on any PWM or servo controller modules. Introduction Controlling Multiple Servos on Raspberry Pi OS Environment Wiring …

This is a memo on how to measure the number of lines in a source code repository. Introduction How to Count Lines of Source Code Count Lines with a Command Count Lines with Tools Conclusion References Introduction While reading source code…

It indicates in-place operations. Introduction Underscore "_" Suffix in PyTorch Function Names Meaning Example Conclusion References Introduction When working with PyTorch, you'll often see functions with a trailing underscore _ in their n…

This is a quick note on how to change the log output level in Terraform. Introduction Outputting DEBUG-Level Logs in Terraform Setting Log Levels Separately for Terraform and Providers Appendix: Reading Terraform's Source Code Conclusion R…

You can easily do this with awk: awk '!seen[$0]++' Introduction Remove Duplicate Lines with One Command Command Breakdown Example Conclusion Reference Introduction This is a quick note on how to remove duplicate lines and show each line on…

A quick overview of the Functional Options Pattern in Go. Introduction Functional Options Pattern in Go Conclusion References Introduction While using a Go-based library, I came across the Functional Options Pattern. Here's a brief note on…

This is a memo on how to implement an MCP server using Golang. Introduction Prerequisite: Is there an official Go MCP SDK? Implementing an MCP Server in Go The Target MCP Server Implementing the MCP server in Go Implementing the Tool Imple…

This is a quick memo on how to use the Rust-based Python package & project manager, "uv". Introduction How to Use uv Installing uv Listing uv Commands Creating a Python Project Creating a Virtual Environment Adding a Python Package Checkin…

This guide summarizes how to use the MCP CLI. Introduction How to Use MCP CLI Installing MCP CLI List of MCP CLI Commands How to Use mcp run How to Use mcp dev How to Use mcp install Conclusion References Introduction MCP CLI is a tool inc…

This is a quick guide on how to use "MCP Inspector," a browser-based test tool for MCP servers. Introduction How to Use MCP Inspector Preparation: Set Up a Minimal MCP Server Launching MCP Inspector Using MCP Inspector Conclusion Reference…

Use MCP to let an LLM play Minesweeper. Introduction Playing Minesweeper via MCP Overview Starting the Minesweeper Server Building the MCP Server Connecting Claude Desktop with MCP Server Letting Claude Play Minesweeper Conclusion Referenc…

This is a quick note to connect Claude Desktop to an MCP (Model Context Protocol) server. Introduction How to Connect Claude Desktop to an MCP Server 1. Add MCP Server Information to the Config File 2. Restart Claude Desktop Conclusion Ref…

Learn about AI agent patterns and practices from Anthropic’s article "Building effective agents" and its follow-up video. Introduction Background: What Is an AI Agent? AI Agent Patterns Augmented LLM Workflow: Prompt chaining Workflow: Rou…

In this post, we'll connect GPT / OpenAI API with MCP (Model Context Protocol), and learn how MCP works. Introduction Recap: What is MCP? Connecting GPT to an MCP Server Implementing the MCP Server Implementing the MCP Client Running the M…