Grzegorz Wierzowiecki gwpl

DECFRA / DECERA and Sixel Graphics Interaction: Research Notes

TL;DR

Whether DECFRA/DECERA clear sixel pixel data is terminal-dependent, not standardised. The VT420 spec defines DECFRA as a text-plane operation only. On real VT340 hardware, DECERA did not affect sixel graphics. xterm added sixel-clearing to DECFRA/DECERA in patch #370 (2021), but this is an xterm extension adopted by some modern terminals.

VT420/VT510 Specification

Understanding SSH Host Aliases ("Pseudo-Domains") for Git Multi-Account

The Core Concept

When you see github.com-work in an SSH config or git remote URL, that is NOT a real domain name. It's an SSH host alias (sometimes called a "pseudo-domain") — a label that only exists in your ~/.ssh/config file. It never hits DNS.

# This is an ALIAS — "github.com-work" is a made-up name
Host github.com-work
 HostName github.com # ← the REAL server to connect to

name	description	argument-hint
lets-brainstorm	Iterative brainstorming interview -- ask creative questions, multi-select to remix, converge to decisions.	<topic or goal to brainstorm about>

Brainstorming Session

Launch an iterative brainstorming interview about the given topic.

Claude Code: Orchestration, Agents, Skills & Hooks — Quick Reference

Companion notes to IndyDevDan's 4-Layer Architecture video. Maps his concepts to Claude Code's built-in primitives.

1. Orchestration → Custom Commands (Reusable Prompts)

Custom commands are markdown files in .claude/commands/ that act as reusable,

Anthropic Claude: Code Ownership & Open Source Licensing Compatibility

TL;DR: Anthropic assigns all rights in Claude outputs to the user. No copyright encumbrance on generated code. Safe for any OSS license (ISC, MIT, Apache-2.0, GPL, etc.).

Official Terms

Consumer Terms (Free/Pro/Max)

"you retain any right, title, and interest that you have in such Inputs" "we assign to you all our right, title, and interest (if any) in Outputs"

AI Agent Instructions — chafa Sixel-via-tmux Bug Reproduction

Context

Bug: chafa (1.14+) auto-detects sixel terminal capability and produces sixel output. When running inside tmux, large sixel payloads (roughly >500KB) fail to render — the image is invisible (blank space) even though chafa exits successfully and produces valid output bytes.

Upstream issue: hpjansson/chafa#327

Quick Setup

Test Report: Sixel Popup Rendering and Cleanup

Date: 2026-02-19 PR: tmux/tmux#4868 Issue: tmux/tmux#4867 Branch: i4867-sixel-display-popup @ 704022a9 Toolkit: tmux Sixel Popup Cleanup Testing Toolkit

Environment

tmux Sixel Popup Cleanup Testing Toolkit

Automated testing infrastructure for verifying sixel image rendering and cleanup in tmux display-popup overlays.

Problem

When a sixel image is displayed inside a tmux popup and the popup closes, pixel artifacts can persist on screen ("ghosting"). This happens because terminal emulators render sixel data in a separate graphics layer that standard

	#!/usr/bin/env bash
	# check-github-license-detection.sh
	#
	# Diagnose GitHub license detection issues for a repository.
	# Checks the API response, inspects license files, and suggests fixes.
	#
	# Usage:
	# ./check-github-license-detection.sh OWNER/REPO
	# ./check-github-license-detection.sh # (auto-detect from current git repo)
	#

	# CadQuery Lego Brick Models — Build all exports
	#
	# Prerequisites:
	# - uv (https://docs.astral.sh/uv/)
	# - For PNG conversion (optional): rsvg-convert, inkscape, or imagemagick
	#
	# Usage:
	# make # build all models (STL + SVG + PNG)
	# make brick # build only the 6x2 lego brick
	# make vase # build only the vase-on-brick model