Flinching occasionally as a blaster bolt hits the nearby bulkhead, a Sullustan mechanic quickly solders a large wire. He peers through his tinted goggles, ignoring the shouts of his ship captain as the enemy descends on the hanger. Finally he shouts with pride as the repaired coupling powers up, causing the frigate to hum with energy. He gathers his tools and runs into the ship moments before it finally takes off.
Inside, the human captain jumps into the cockpit. She nods to her droid co-pilot, who quickly begins charting a course home. Before the calculations can be completed, enemy Starfighters scream in from the clouds. The pilot rolls the ship, nimbly evading incoming fire. She reroutes the power to shields, leaving just enough for astronavigation. Just as the energy reserves near depletion, the exosphere and stars beyond blur into streaks of light. In a flash, they warp to safety.
A Cerean officer surveys the battlefield, looking for weaknesses. When he identifies a potential problem, he keys in a quick combination in his wristpad. In a blink, a custom suit of armor assembles itself around him. As the helmet locks into place, the officer leaps into the air, flying overhead and raining destruction on the opposition.
Every machine needs an engineer to run it, and a living crew is no different. Engineers are the experts and professionals who rely on skill, bravery, and their tools to survive and keep others alive. While they do not claim to be fighters, their mere presence can turn the tide of battle or simply keep operations running  

Behind the Curtain

While perhaps not as intimidating as a heavily-armored trooper, or as exotic as a lighsaber-wielding guardian, engineers are no less vital to group dynamic. They are armorers and gunsmiths, electricians and welders, or any other facet to be found in facilities across the galaxy. Their work, often unsung, is what keeps starships (and their crew) intact.  

Unflappable

It takes bravery for a soldier to enter a battlefield. It perhaps takes more for someone who is unarmed, and untrained in combat, to do the same. Engineers put their lives on the line for a living, whether by choice or acknowledging their plights as an occupational hazard. Whether they come from an elite training academy or learned their talents surviving in the slums, they are no strangers to danger and conflict.
While creating your engineer character, consider what your primary skill set is and how you use it. You could be a street-smart mechanic who taught yourself how to fix swoop bikes as a teenager. Perhaps you are the recent graduate of an esteemed medical college, or a rookie pilot in the fledgling Rebel Alliance. What is the number one skill you are known for? Why are you willing to enter battles when you have no combat training? How do you view the more adventurous members of your group, and how do they see you and your role?  

Quick Build

You can make an engineer quickly by following these suggestions. First, make Intelligence your highest ability score. Your next-highest score should be Constitution. Second, choose the scientist background.

(a) a simple vibroweapon or (b) a simple blaster and two power cells
(a) a dungeoneer’s pack or (b) an explorer’s pack
Combat suit, a set of tinker’s tools, a vibrodagger, and a wristpad

Tech Powers Known

You learn 6 tech powers of your choice, and you learn more at higher levels, as shown in the Tech Powers Known column of the engineer class table. You may not learn a tech power of a level higher than your Max Power Level.  

Tech Points

You have a number of tech points equal to your engineer level x 2, as shown in the Tech Points column of the engineer class table, + your Intelligence modifier. You use these tech points to cast tech powers. You regain all expended tech points when you finish a short or long rest.  

Max Power Level

Many tech powers can be overcharged, consuming more tech points to create a greater effect. You can overcharge these powers to a maximum level, which increases at higher levels, as shown in the Max Power Level column of the engineer class table.
You may only cast tech powers at 6th, 7th, 8th, and 9th-level once. You regain the ability to do so after a long rest.  

Techcasting Ability

Intelligence is your techcasting ability for your tech powers. You use your Intelligence whenever a power refers to your techcasting ability. In addition, you use your Intelligence modifier when setting the saving throw DC for a tech power you cast and when making an attack roll with one.
Tech save DC: 8 + your proficiency bonus +your Intelligence modifier
Tech attack modifier : your proficiency bonus +your Intelligence modifier

Potent Aptitude

Your technological experience lends you an uncommon insight that you can use to bolster your allies. To do so, you use a bonus action on your turn to choose one creature other than yourself within 60 feet of you who can hear you. That creature gains one Potent Aptitude die, a d6.
Once within the next 10 minutes, the creature can roll the die and add the number rolled to one ability check, attack roll, or saving throw it makes. The creature can wait until after it rolls the d20 before deciding to use the Potent Aptitude die, but must decide before the GM says whether the roll succeeds or fails. Once the Potent Aptitude die is rolled, it is lost.
A creature can have only one Potent Aptitude die at a time.
You can use this feature a number of times equal to your Intelligence modifier (a minimum of once). You regain any expended uses when you finish a long rest.
Your Potent Aptitude die changes when you reach certain levels in this class. The die becomes a d8 at 5th level, a d10 at 10th level, and a d12 at 15th level.  

Infuse Item

At 2nd level, you gain the ability to temporarily enhance a weapon or armor. At the end of a long rest, you can touch one unenhanced object that is a suit of armor or a simple or martial weapon. Until the end of your next long rest or until you die, the object becomes an enhanced item, granting a +1 bonus to AC if it’s armor or a +1 bonus to attack and damage rolls if it’s a weapon. Once you’ve used this feature, you can’t use it again until you finish a long rest.  

Tool Understanding

Also at 2nd level, you have advantage on any ability check you make that uses any of the tool proficiencies you gain from this class.  

Ability Score Improvement

When you reach 4th level, and again at 8th, 12th, 16th, and 19th level, you can increase one ability score of your choice by 2, or you can increase two ability scores of your choice by 1. As normal, you can’t increase an ability score above 20 using this feature. Alternatively, you can choose a feat (see Chapter 6 for a list of feats).  

Quick Thinking

Beginning when you reach 5th level, you regain all of your expended uses of Potent Aptitude when you finish a short or long rest.  

Tech Mastery

At 20th level, your mastery of technology is unrivaled. Your Constitution and Intelligence scores increase by 2. Your maximum for those scores increases by 2.
Additionally, when you roll initiative and have no uses of Potent Aptitude left, you regain one use.