STDweb: simple transient detection pipeline for the web

We present a simple web-based tool, STDWeb, for a quick-look photometry and transient detection in astronomical images. It tries to implement a self-consistent and mostly automatic data analysis workflow that would work on any image uploaded to it, allowing to perform basic interactive masking, object detection, astrometric calibration of the image, and building the photometric solution based on a selection of catalogues and supported filters, optionally including the colour term and positionally varying zero point. It also allows you to do image subtraction using either user-provided or automatically downloaded template images, and do a forced photometry for a specified target in either original or difference images, as well as transient detection with basic rejection of artefacts. The tool may be easily deployed allowing its integration into the infrastructure of robotic telescopes or data archives for an effortless analysis of their images.