Millions of molecules are made of repeating units of individual building blocks (monomers). DNA and RNA are important natural polymers made of repeating nucleotides as building blocks. The manufacture of short strands of chemically modified RNA (oligonucleotides) has shown great promise for the development of novel therapies. It is currently achieved using solid-phase synthesis in which the growing oligo is bound to an insoluble substrate and monomers are added one at a time. Solid-phase synthesis is difficult to scale and the resulting purity is low, leading to high prices. The UK start-up Exactmer has developed patented technology enabling polymer synthesis entirely in the liquid phase to overcome these obstacles. The EU-funded NANOLIGO project will bring this technology to market with the potential to significantly speed the development of novel complex polymeric pharmaceuticals and slash manufacturing costs.