Abstract Motivation New long read sequencers promise to transform sequencing and genome assembly by producing reads tens of kilobases long. However, their high error rate significantly complicates assembly and requires expensive correction steps to layout the reads using standard assembly engines. Results We present an original and efficient spectral algorithm to layout the uncorrected nanopore reads, and its seamless integration into a straightforward overlap/layout/consensus (OLC) assembly scheme. The method is shown to assemble Oxford Nanopore reads from several bacterial genomes into good quality (∼99% identity to the reference) genome-sized contigs, while yielding more fragmented assemblies from the eukaryotic microbe Sacharomyces cerevisiae. Availability and implementation https://github.com/antrec/spectrassembler. Supplementary Information Supplementary data are available at Bioinformatics online.