Andrey Breslav, the original creator of the Kotlin programming language, has launched CodeSpeak, a development approach that uses LLMs to generate production code from plain-text markdown specification files. Rather than writing or maintaining code directly, developers keep concise spec files that CodeSpeak's CLI tool uses to regenerate code on demand. The project, currently in alpha and installable via `uv tool install codespeak-cli`, targets engineering teams building long-term production systems — explicitly positioning itself as distinct from the "vibe coding" trend and aimed at organizations where human communication and maintainability matter. Breslav founded CodeSpeak in 2025 after a decade leading Kotlin at JetBrains and a subsequent five years co-founding Alter.ru, an online mental health platform based in Eastern Europe.
The headline claim is a 5–10x reduction in codebase size. CodeSpeak has published case studies against four popular open-source Python projects: WebVTT subtitle support in yt-dlp shrank 6.7x (255 lines of code to 38 lines of spec), an Italian SSN generator in Faker shrank 7.9x, encoding detection in beautifulsoup4 shrank 5.9x, and an EML converter in markitdown shrank 9.9x. In each case, the project reports that existing tests continued to pass, and in all four cases new tests were added after conversion. The tool supports "mixed projects" where some code remains manually written alongside spec-generated code, and the team recently shipped modularity features including spec dependencies and managed files.
Despite the "next-generation programming language" branding, the Hacker News community has broadly characterized CodeSpeak as a workflow or tooling layer rather than a language in any formal sense. The core technical criticisms are substantive: LLM non-determinism means re-running a spec can produce different code each time, threatening reproducibility; and the underspecification problem compounds as codebases grow. The sharpest philosophical objection is also the oldest — Joel Spolsky made the case in his 2000 writing on functional specifications that a spec detailed enough to reliably produce correct code is roughly as hard to write as the code itself. The argument maps cleanly onto CodeSpeak's central claim. Breslav has engaged these objections directly, including a seminar at Cambridge University's Department of Computer Science and Technology titled "From Kotlin to CodeSpeak," where he argued that keeping humans in control of the software development lifecycle becomes more important, not less, as AI capabilities increase. The alpha is available now for teams willing to test the approach on real codebases — how it holds up at scale, across large mixed projects, will determine whether the language design community treats it as a new paradigm or an elaborate spec-management workflow.