March 2026 sponsors-only newsletter

2026-04-02 · Source: Simon Willison's Weblog · Field: Technology & Digital — Artificial Intelligence & Machine Learning, Software Development & Engineering, Cybersecurity & Data Privacy · Depth: Advanced, quick

Summary

The March 2026 edition of a sponsors-only monthly newsletter, released on April 2, 2026, covers several technical topics for professional readers. Key subjects include advanced agentic engineering patterns and techniques for streaming Mixture-of-Experts (MoE) models on macOS devices. The newsletter also provides an overview of new model releases from March, discusses "Vibe porting," and analyzes recent supply chain attacks targeting package managers like PyPI and NPM. Additional sections detail the author's recent project shipments, their preferred tools and technologies for March 2026, and mentions a couple of museums. A February newsletter copy is available as a preview for prospective sponsors.

Key takeaway

For engineering leaders and AI/ML practitioners evaluating current trends, your teams should review the March 2026 newsletter's insights on agentic engineering and MoE model deployment. Pay particular attention to the discussion on supply chain attacks against PyPI and NPM to bolster your software security posture and mitigate potential risks.

Key insights

The March 2026 newsletter covers agentic engineering, MoE streaming on Mac, model releases, and supply chain security.

In practice

• Explore agentic engineering patterns.
• Investigate MoE model streaming on macOS.
• Monitor PyPI/NPM for supply chain attacks.

Topics

• Agentic Engineering
• MoE Models
• Supply Chain Attacks
• PyPI
• NPM

Code references

• sponsors/simonw
• simonw-private/monthly

Best for: CTO, VP of Engineering/Data, Director of AI/ML, AI Engineer, Machine Learning Engineer, AI Scientist

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Editorial summary, takeaway, and curation by AIssential. Original article published by Simon Willison's Weblog.