TaxWorld, an online tax library operating mainly in Ireland and the UK, built Ezylia, an expert AI tax assistant, on CustomGPT.ai's no-code platform. Ezylia has received 189,351 queries, of which 184,690 (97.5%) were answered by the AI, and now handles over 2,000 questions a day. CustomGPT.ai's case study says this helped the lean startup double its annual recurring revenue to close to EUR 1m in 24 months while saving 500+ hours per week.
According to Alan Moore, Founder & CEO of TaxWorld, "CustomGPT.ai let us punch far above our weight. With almost no engineering budget, we built an assistant that now answers tens of thousands of complex tax questions and fuels our revenue growth every month."
TaxWorld set out to make accurate, trusted tax guidance accessible to small accounting firms, which typically employ fewer than ten people. Accountants at those firms were drowning in dense legislation, guidance, and case law; existing solutions like Tolley in the UK served larger firms but were unaffordable and cumbersome for smaller practices. Pain points included time-intensive research cutting into billable hours, inconsistent quality across sources, and no scalable way to deliver instant, accurate tax answers. The root cause was a lack of affordable tools with built-in domain knowledge, since market incumbents catered only to top-tier firms and generalist AI models lacked the depth and precision of TaxWorld's knowledgebase.
CustomGPT.ai's no-code platform aligned perfectly with TaxWorld's lean strategy, letting the company deploy Ezylia within days and without technical staff. Ezylia was rapidly connected to thousands of legislative documents, tribunal decisions, and case law, leveraging CustomGPT.ai's 100 one-click data integrations and support for 1,400 file types. TaxWorld used CustomGPT.ai's RAG and accuracy architecture for real-time, citation-backed answers, and no-code tools to launch a friendly, on-brand assistant integrated into its redesigned website. The platform's infrastructure scales as TaxWorld expands its customer base and legal catalogue.
Beyond the headline metrics, TaxWorld reports 740 paying subscribers with only eight cancellations since launch, and Ezylia answers 2,000+ questions daily and rising. Instant citations replace hours of manual research, and instant replies (letters and emails) handle client queries. TaxWorld also maintains a "human" members Q&A area where answers obtained in the forum are automatically added to Ezylia's brain for future reference.
According to the vendor, the deployment worked because the non-technical platform enabled founder-led rapid testing and time-to-value, non-engineers could scale with confidence, and answers generated directly from source material with attached citations built trust with accountants who cannot tolerate hallucinations. Data security meant full control of proprietary legal data with no training or leakage. As a next step, TaxWorld is rapidly expanding into the UK and US markets.