If sigi doesn't do quite what you want, check out these similar projects. Sigi was created before I found these, but some inspiration may be gleaned from them for improvement. Most in this list predate sigi by several years.
- devtodo - A hierarchical command-line task manager
- dstask - Single binary terminal-based TODO manager with git-based sync + markdown notes per task
- geek-life - The CLI To-Do List / Task Manager for Geeks
- grit - Multitree-based task manager
- node-todo-cli - A command line program that manages todo tasks
- py-todo-cli - A simple command line Todo program written in Python
- taskell - Command-line Kanban board/task management
- taskwarrior - Taskwarrior is Free and Open Source Software that manages your TODO list from the command line
- tax - CLI task list manager
- todo cli - Todo CLI is a simple program that uses a sqlite3 database to keep track of your tasks
- todo.txt - Future-proof task tracking in a file you control
- ultralist - Command-line task management for tech folks
- yokadi - Yokadi is a command line oriented, sqlite powered, todo-list
- gophercises #7: task - TODO CLI definition. (Defines a CLI)
- pushpop - "Mental stack manager" definition. (Defines both a GUI and CLI)
- See also implementations in sh, power shell
- GTG (Getting Things GNOME!)
- KTimeTracker
- But really... Just too many to list? TODO apps are kind of the canonical JavaScript "first big project." They're also ubiquitous in mobile app stores.
- piladb - Stack-based database. (A working REST API and Database)