Unicycler is a novel tool designed to assemble bacterial genomes from a combination of short and long sequencing reads, aiming to produce accurate, complete, and cost-effective assemblies. The tool first uses SPAdes to assemble short reads into an initial assembly graph, which is then simplified using information from both short and long reads. Unicycler employs a semi-global aligner to align long reads to the assembly graph, allowing for the creation of bridges that resolve repeats and improve contig quality. Tests on both synthetic and real reads demonstrate that Unicycler can produce larger contigs with fewer misassemblies compared to other hybrid assemblers, even with low long-read depth and accuracy. The tool is open-source and available on GitHub, offering a valuable resource for researchers aiming to assemble bacterial genomes using a combination of short and long sequencing data.Unicycler is a novel tool designed to assemble bacterial genomes from a combination of short and long sequencing reads, aiming to produce accurate, complete, and cost-effective assemblies. The tool first uses SPAdes to assemble short reads into an initial assembly graph, which is then simplified using information from both short and long reads. Unicycler employs a semi-global aligner to align long reads to the assembly graph, allowing for the creation of bridges that resolve repeats and improve contig quality. Tests on both synthetic and real reads demonstrate that Unicycler can produce larger contigs with fewer misassemblies compared to other hybrid assemblers, even with low long-read depth and accuracy. The tool is open-source and available on GitHub, offering a valuable resource for researchers aiming to assemble bacterial genomes using a combination of short and long sequencing data.