Jelly

Jelly is an APL-like language inspired by J. It extends J with many built-ins intended to give Jelly an advantage in code golf, e.g. divmod, the hash function, and string compression. Jelly uses different terminology from normal APL usage. Built-in functions are called atoms, while derived functions are called links. Newlines or statement separators are used to separate links, the last line of the program (chain) is called the main link.
 * Like K, Jelly uses the list model for its arrays.
 * Like APL, Jelly uses a wide range of Unicode glyphs. However, Jelly extends the glyph set to 256 characters from the US International keyboard, as well as the addition of 2-character digraphs.
 * Unlike any other language in the APL family, Jelly atoms have a fixed valence, making Jelly appear more like a stack-based language, and obviating the need for parentheses.

Some constructs clearly show Jelly lineage through J to APL, e.g. summation can be written as  (although Jelly also has a dedicated built-in for this).