Icestudio is an open-source graphical FPGA design and programming environment. It allows users to create digital circuits by dragging, dropping, and wiring blocks representing logic elements, I/O, constants, memory, and code. The tool then compiles the design into Verilog, runs the open-source FPGA toolchain (yosys, nextpnr, apio) to generate a bitstream, and uploads it to a wide variety of Lattice iCE40 and ECP5 boards. The application is built as a desktop app using NW.js (Node.js + Chromium) with an AngularJS 1.x frontend, JointJS for diagramming, and a custom plugin system for extensibility. It supports over 60 FPGA boards, includes a package manager (iceHub) for block collections, a serial terminal plugin, a board editor, and an integrated toolchain shell. The codebase is mature but relies on several deprecated technologies (AngularJS, NW.js, Grunt) and lacks automated tests, making modernization risky. Key reusable elements include the event bus, plugin manager, orthogonal wire router, and file system indexer.