Ruby on Rails creator DHH joins the praise for Claude Opus 5.5

David Heinemeier Hansson, the creator of Ruby on Rails and co-owner of 37signals, has joined the early praise for Anthropic’s Claude Opus 5.5.

“The hype is true. Anthropic did magic with Opus 5.5. Damn it’s good,” Hansson wrote on X on September 27. The post did not identify a benchmark, workload or comparison model, so it should be read as a prominent developer’s firsthand endorsement rather than an independent test.

The endorsement lands after a cheaper Opus release

Anthropic released Claude Opus 5.5 on September 22 as the first model in its 5.5 family. The company says it performs at roughly the level of Claude Fable 5.1 on most work while costing about 40% less than Opus 5 under typical default settings.

List pricing fell to $4 per million input tokens and $20 per million output tokens. Anthropic also says output is more than 30% faster, and it has emphasized the model’s ability to sustain longer agentic tasks involving coding, research and tool use.

Those changes matter to working developers because a model can feel substantially more useful without winning every public benchmark. Lower latency, fewer failed tool calls and a lower per-task cost can change whether an agent is practical for routine work.

Hansson’s post does not establish those gains across users or applications. It does show that Opus 5.5 is drawing enthusiasm from a developer whose frameworks and products have influenced how web software is built, adding a recognizable practitioner’s voice to Anthropic’s launch claims.