Opus 4.5 changed everything (Interview)

What It Covers

Adam Stacoviak of The Changelog interviews Burke Holland from GitHub Copilot about how Claude Opus 4.5, released around December 2024, created a measurable step-function improvement in agentic coding capability. The conversation covers practical AI-assisted development workflows, the economics of subsidized model access, the future of software craftsmanship, and whether developers will be replaced or transformed into polymaths.

Key Questions Answered

• •Agentic Model Quality Threshold: Sonnet 3.5 could build agentically but produced sloppy, spaghetti code that stalled on errors neither the developer nor the model could debug — because the developer hadn't written the code themselves. Opus 4.5 crossed a threshold where it one-shots functional native Windows tools using correct WinUI libraries, produces well-structured readable code, and completes full working apps in an afternoon. The practical test: Burke built a screen-capture-to-GIF tool, then extended it into a full screen recording editor in a few hours.
• •Personal Software Economics — The SaaS Killer Pattern: When a model reaches sufficient capability, replacing paid SaaS subscriptions with custom-built personal software becomes viable in a single afternoon. Burke replaced a paid routing app his wife used for her yard-sign business. Adam replaced an $500–$800/year invoicing service by prompting Claude Opus 4.6 with extended thinking to generate an optimal prompt, then handing that prompt to Augment Code's Auggie CLI overnight — waking to a working Rails app with invoicing, PDF generation, and email built in.
• •Subsidized Token Economics Won't Last: GitHub Copilot at $40/month offers request-based billing where one agent run doing 6,000 operations counts as a single request, with 1,500 requests per month included. Claude's $200/month max plan supports roughly one billion tokens monthly at an estimated provider cost of $25,000 — a $24,800 subsidy per user. Burke explicitly states this pricing cannot persist indefinitely and developers should maximize usage now, treating the current window as a finite opportunity before costs normalize.
• •Plan Mode as Context Extraction, Not Documentation: The value of agent plan mode is not producing a written plan — it is forcing the model to surface all the requirements and constraints the developer forgot to specify in the initial prompt. Running four to six planning loops with Opus 4.6 before execution dramatically improves output quality. Burke's current workflow: plan mode in Copilot CLI