Teleport Cleans Codebase With LLMs in 90-Day Trial
A team of 13 engineers at Teleport spent 90 days using large language models to clean their codebase, discovering that prompt quality outweighs quantity when finding security vulnerabilities.
The software security firm Teleport recently concluded a 90-day internal experiment to evaluate the efficacy of large language models in securing and cleaning up legacy code. A team of 13 engineers participated in the project, which the company described as "pressure washing" their existing codebase using AI-assisted tools to identify and patch security vulnerabilities.
The primary takeaway from the three-month initiative is that the quality of LLM interactions matters far more than the sheer volume of automated scans. When attempting to locate complex security flaws, the engineers found that highly targeted, high-quality prompts yielded significantly better results than running massive, unrefined batches of AI queries. This insight challenges the common industry practice of deploying LLMs as bulk, automated code-sweepers without careful human oversight and prompt engineering.
For software development practitioners and security teams, the Teleport experiment highlights a shift in how AI tools should be integrated into the development lifecycle. Instead of relying on LLMs for broad, superficial sweeps, developers should focus on crafting precise, context-aware instructions to uncover deep-seated vulnerabilities. This approach ensures that engineering teams do not get overwhelmed by false positives while still leveraging the speed of generative AI to fortify their software. Ultimately, the 90-day trial demonstrates that human expertise in guiding the AI remains the critical factor in successful codebase maintenance.
This is our own summary of reporting by Simon Willison



