DSL4 Digital is an independent software and AI company based in the Canary Islands, Spain. It designs, develops and operates its own digital products, alongside the technology and engineering behind them. Its portfolio combines commercial software offered by subscription or licence with open-source developer tools, including MIT-licensed projects.

DSL4’s products address research, education, data recovery, commerce, compliance and practical information needs. RefExists helps researchers and AI agents verify scholarly citations, while Versos turns poetry into a multilingual language-learning experience with native-voice audio and spaced repetition. Mendery recovers content from damaged documents and SQLite files in the browser without uploading files. Other offerings include Papertill for digital-download payments and delivery, Drumbola for verifiable prize draws, and VeriSovereign for invoice integrity and AEAT submission preparation.

The company also develops tools for legal evidence organisation, AI-agent interaction, labour-agreement monitoring, public-grant discovery and Spanish holiday data. Its consumer and editorial work includes ORIELA, a financial-education platform for women aged 60 and over, and DSL4 Newsroom.