Where were the earlier posts published?
On CSDN from the summer of 2025 (blog.csdn.net/2401_87876529) — Python and data analysis first, then transformers, LLMs, and agents. New writing moved here in September 2026; the old posts stay up but are no longer updated.
From the summer of 2025 until September 2026 the writing lived on CSDN — about twenty posts: https://blog.csdn.net/2401_87876529
The first half was fundamentals: Python data structures, NumPy and pandas, then data analysis and visualization, with a few competitions and small projects in between. The second half turned to AI — from transformers through tool calling, the agent loop, multi-agent setups, and Claude Code, plus engineering questions like prompt-injection defences and agent checkpoints.
New writing happens here now; the CSDN archive stays online but is no longer updated. Moving also meant re-ordering the old notes: the transformer piece was rewritten into its current shape after the move, and the move itself is written up in the note From CSDN to a site of my own.