Last November, Buymie, the same-day grocery delivery start-up, was ranked by Deloitte as Ireland’s fastest-growing technology company after it recorded growth of 6,903 per cent over the previous four years. Now, however, the Irish retail giant Dunnes Stores, one of Buymie’s key commercial partners, is in talks to acquire the company for a relatively small sum. The deal would safeguard the business and its staff, but would see its backers take a big write-down on their investments. Buymie, led by the entrepreneur Devan Hughes, has raised more than €18 million through a series of funding rounds, including a €7 million…