# J programming language

23 Hacker News commenters recommended J programming language and 10 criticized it, November 2025 to November 2026. It was recommended in 8 of 13 months. It meets the Hacker Approved badge rule.

**Verdict:** People recommend J for its terse array-based syntax, free open-source implementation and learning materials; critics find its tacit syntax and symbols hard to learn and remember.

## Why people recommend it

- Terse, short code (4 comments): "I still love the atoms and terseness of array languages and writing close to the metal." ([source](https://news.ycombinator.com/item?id=47041810)) "I very appreciate this language for shortness but this kind of shortness might annoy." ([source](https://news.ycombinator.com/item?id=46583868)) "The J answers tend to be very short and very fast." ([source](https://news.ycombinator.com/item?id=46262205))
- Free with extensive learning materials (2 comments): "J is FOSS, J has extensive learning materials, and J is reasonably batteries-included" ([source](https://news.ycombinator.com/item?id=46721804)) "The intro books for J are great for working through math and learning J" ([source](https://news.ycombinator.com/item?id=47755814))
- Powerful for number-crunching (2 comments): "J is for number munching, Lisp is for everything else." ([source](https://news.ycombinator.com/item?id=46746370)) "it would be hard to make the case that it lacks power" ([source](https://news.ycombinator.com/item?id=46261399))
- Gentle learning curve (2 comments): "A few nights playing with J and learning was enough to not be completely lost and able to make some progress, but it is still a challenge." ([source](https://news.ycombinator.com/item?id=46260548)) "its learning curve isn't steep" ([source](https://news.ycombinator.com/item?id=46723630))

## What people warn about

- Dense syntax hard to read (4 comments): "the end result is that my solutions become too alien for the general practitioner" ([source](https://news.ycombinator.com/item?id=49071683)) "I find it worse to use single letter names for functions" ([source](https://news.ycombinator.com/item?id=46264217)) "this syntax is almost as bad as that of TypeScript" ([source](https://news.ycombinator.com/item?id=46270339))
- Poor fit for databases and apps (3 comments): "it has been made mostly for math so it is not optimized for CRUDs" ([source](https://news.ycombinator.com/item?id=46488745)) "they cannot be used with sql databases or existing python libraries" ([source](https://news.ycombinator.com/item?id=49872158)) "It may be not efficient at all for using rich types and structs" ([source](https://news.ycombinator.com/item?id=46490968))

## Alternatives hackers recommend

- [Uiua](https://hackerapproved.com/p/uiua.md): 20 recommend
- [BQN](https://hackerapproved.com/p/bqn.md): 11 recommend
- [K programming language](https://hackerapproved.com/p/k-programming-language.md): 11 recommend
- [kdb+ q](https://hackerapproved.com/p/q.md): 7 recommend
- [l runtime for k and q](https://hackerapproved.com/p/l.md): 6 recommend

## Cite as

Hacker Approved, "J programming language", https://hackerapproved.com/p/j-programming-language/ (counts from 1,795,640 Hacker News comments, November 2025 to November 2026).