EDIT: There are reports that this achievement is not unlocking properly for users who don't have the DLC (because there are additional gadgets in the DLC). The developers have stated on Twitter that this will be fixed in an upcoming patch.
https://twitter.com/ChariotGame/status/652106444230279168There are six gadgets to unlock in Chariot. Not to be confused with upgrades for the chariot itself, each player can select a gadget prior to each level. To unlock a gadget in the store, its blueprint must be found in a level first.
The Peg gadget has blueprints in levels 1-2, 3-2, and 4-1.
The Canary gadget has blueprints in levels 1-4, 2-3, and 3-5.
The Sprint gadget has blueprints in levels 2-1, 4-2, and 5-1.
The Repulsor gadget has blueprints in levels 2-4, 3-4, and 4-4.
The Slowdown gadget has blueprints in levels 3-1, 4-3, and 5-2.
The Attractor gadget has blueprints in levels 3-3, 4-5, and 5-3.
So you can get this achievement after level 3-3 at the earliest.