I only know javascript so far but have been dabbling a bit with C#..
so I guess I'll be using javascript. I'll try to incorporate my photoshop experience into this project more than past projects.
I'm still really inexperienced  (started learning in July) and have only made a solitare and asteroids game, so I'm looking forward to learning something new.
I've never done a game jam before and I hope the community experience is better than just plunkin away by myself.
I also have a 3 year old and a 2 month old, and kids will probably take away from my coding time, so altogether my project prolly isn't gonna be nearly as good as some of you guys' haha.

Probably the piston engine in Rust, because I like the language. 

Ill use c++/sfml since Ive had experience with it

Probably going to go with olc::PGE. hopefully I can get a modest but whole game out of this! 

i've got a lot of free time and not much to do with it so i'm trying out a new framework called ggez in Rust

first ever game jam too woohoo :p

I'll be using my engine I've made with over the past few months (C++ /OpengGL/GLFW). Great opportunity to see where improvement is needed! 

I will use UE4 because I Just started learning and it will be a great motivation

My first jam! I'm gonna use unity and maybe some assets because it sounds simple enough.. hope I can finish

Depending on the theme i will be using Unity or Unreal Engine. If its something special i will be using a custom engine.

always wanted to learn c++, raylib sounds pretty cool, I might try it.

SFML and C++, just cause i know them well and library is pretty straightforward.

I'm running with Game Maker Studio 2

C++ no external libraries. Only Windows and std.

I'm either gonna play about with PyGame, or with the JS HTML DOM and canvas.

C++ with SFML. Started using SFML only recently.

I will use Monogame / Xna Framework (C# ).

Probably c++, as it is the language i am most profitient at, and sfml for the graphics.

I'm using my kernel I wrote, it has just enough components to handle a game

Scientific programmer here. All I know is Matlab...

I use the Godot game engine.

olc::PixelGameEngine of course. Its all that I could ever need. Opengl without me doing the gl.

Im good at making and compiling flash!

This will be my first ever project with C.  I'm going to keep it very simple, probably text-based.

Here goes nothing!

I'm gonna use PICO-8