The Thargoids are coming! The Thargoids are coming!
Okay, so that’s probably an overreaction, or maybe it isn’t. It could be a race of peaceful fish. We don’t know. But just in case…
…I need to unlock the Engineers. All the Engineers. Since many of these esteemed individuals require an introduction from each other, you need to unlock Engineers you might not want to deal with in order to gain access to the ones you do want interact with.
Some Engineers have short-cuts, but to unlock levels by building reputation with them, you need to upgrade modules. In many cases the higher level upgrades require rare commodities and materials and data, but the level 1 upgrades don't, so...
A fast way to do to this is to repeatedly generate a low-cost level 1 upgrade that requires an abundant material, such as carbon.
If the Engineer is a prerequisite to another Engineers introduction, then your introduction message will be sent to you when you have unlocked the first Engineer to level 3 and 33% (to level 4).
I've managed to upgrade my primary ships to all have level 5 FSD upgrades, which means my Anaconda now jumps over 40Lyr unladen!
However, if I am going to have super-dooper shields and kill-em-dead lasers, I need to unlock a few other Engineers first.
Who are the Engineers and what do they do?
Here’s a quick list of the fifteen Engineers discovered so far. The numbers indicate the level of upgrade they provide. Each Engineer is discovered an unlocked by a variety of criteria. Thanks to CMDRs Huntemdown and Sir Clip for providing some of the information here.
Broo Tarquin
Muang 
Muang 5A 
Broo's legacy
Learn about: reach level 3 and 33% reputation with Hera Tani.
Gain access: when you reach Competent or higher combat rank.
Initial contract: 50T of Fujin Tea - obtain this from Futen Spaceport at Fujin.
Modules / maximum level: Beam lasers 
, Burst lasers 
, Pulse lasers 
Short-cut to reputation: none.
Colonel Bris Dekker
Sol Iaptus Dekker's yard
Learn about: reach level 3 and 33% reputation with Juri Ishmaak.
Gain access: reach Friendly status with the Federation.
Initial contract: 10,000,000CR of Combat Bonds (double-ouch!).
Modules / maximum level: Frame Shift Drives , Frame shift drive interdictors
Short-cut to reputation: none.
NOTE: Sol is a permit-only system so you will also need to earn a Sol permit by doing missions for the Federation and attaining the rank of Petty Officer (rank 4) in the Federal Navy.
Didi Vatermann
Leesti Leesti 3A Vatermann LLC
Learn about: reach level 3 and 33% reputation with Selene Jean.
Gain access: reach the rank of Merchant or higher.
Initial contract: 50T of Lavian Brandy - this is a rare commodity purchased at Lave Station in Lave, but can only be bought in volumes of 3-6T, so you'll have to make multiple trips.
Modules / maximum level: Shield boosters 
, Shield Generators
Short-cut to reputation: Sell goods at Vatermann LLC station.
Elvria Martuk
Khun Khun 5 Long sight base
Learn about: revealed by default.
Gain access: travel at least 300lyr away from your start system.
Initial contract: 3T of Sooltil relics - obtain from Soontil at Cheranovsky City station in Ngurii.
Modules / maximum level: Frame Shift Drives , Shield Generators , Thrusters 
, Shield Cell Banks
Short-cut to reputation: Sell her cartographic data.
Felicity Farseer
Deciat Deciat 6A Farsee Inc
Learn about: revealed by default.
Gain access: reach the rank of Scout in Exploration.
Initial contract: 1T of Meta-Alloys - obtain from Darnielle's Progress planetary base in Maia.
Modules / maximum level: Frame Shift Drives , Frame shift drive interdictors , Power generators , Shield boosters , Thrusters
Short-cut to reputation: Sell her cartographic data.
NOTE: Farseer Inc also sells Enhanced Performance Thrusters at the station outfitting. These can be bought regardless of the Engineer unlock state. EPT's come in Class 2A and Class 3A only.
Hera Tani
Kuwemaki Kuwemaki A 3A The jet's hole
Learn about: reach level 3 and 33% reputation with Liz Ryder.
Gain access: reach an Imperial Navy rank of Outsider or higher.
Initial contract: 50T of Kamitra Cigars - obtain these at Hammel Terminal in Kamitra.
Modules / maximum level: Power distributors , Power Generators
Short-cut to reputation: Sell goods at The Jet's Hole station.
Juri Ishmaak
Giryak Giryak 2A Pater's memorial
Learn about: reach level 3 and 33% reputation with Felicity Farseer.
Gain access: when you have earned more than fifty combat bonds.
Initial contract: 1,000,000CR of combat bonds (ouch!).
Modules / maximum level: Mine launchers , Missile racks , Torpedo pylons
Short-cut to reputation: Handing in combat bonds at Pater's Memorial station.
Lei Cheung
Laksak Laksak A1 Trader's rest
Learn about: reach level 3 and 33% reputation with The Dweller.
Gain access: when you have bought or sold goods at fifty different stations.
Initial contract: 200T of gold, which can be bought in system from Laumer City or West City stations.
Modules / maximum level: Shield boosters , Shield Generators
Short-cut to reputation: Sell goods at Trader's Rest station.
Liz Ryder
Eurybia Makalu Demolition unlimited
Learn about: revealed by default.
Gain access: take missions for or trade with Eurybia Blue Mafia in the Eurybia system until you reach a Cordial state with the faction.
Initial contract: 200T of Landmines, which can only be bought at planet bases (such as Leonov Depot in Alpha Caeli, Eckford Survey in LHS 1651 or Dedekind Bastion in Njojujil).
Modules / maximum level: Armour , Hull reinforcement packages , Mine lauchers , Missile racks , Torpedo pylons
Short-cut to reputation: Sell goods at Demolition Unlimited base.
Marco Qwent
Sirius Lucifer Qwent research base
Learn about: reach level 3 and 33% with Elvira Martuuk.
Gain access: by invitation from Sirius Corporation - this is obtained by taking mission for the faction at Sirius until you reach Allied status with Sirius Corporation.
Initial contract: 25T of Modular Terminals - obtain these from missions for Sirius Corporation at Efremov Plant planetary base, close to Qwent Research base.
Modules / maximum level: Power distributors , Power Generators
Short-cut to reputation: Sell her cartographic data.
NOTE: The Sirius system is a permit-only system and can only be accessed by completing missions for Sirius Corporation until you reach Allied status with the faction. Procyon is a system where your can find Sirius Corporation missions.
Professor Palin
Maia Maia A 3A Palin research centre
Learn about: reach level 3 at 33% reputation with Marco Qwent.
Gain access: when you have visited a system at least 5,000Lyr from your original start system.
Initial contract: 25T of Unknown Fragments - these are found by visiting HIP 14479 and looking for Signal Sources called "Anomaly Detected [Threat 4]". In these you will find an Unknown Artifact floating in space. You need to carefully shoot this object so it shatters and collect the fragments. Each bit you collect contains 3 Unknown Fragments.
Modules / maximum level: Frame Shift Drives , Thrusters
Short-cut to reputation: Sell him cartographic data.
Selene Jean
Kuk Kuk 3B Prospector's rest
Learn about: reach level 3 and 33% with Tod McQuinn.
Gain access: when you have mined 500T or more.
Initial contract: 10T of Painite - this can only be obtain from mining.
Modules / maximum level: Armour , Hull reinforement packages
Short-cut to reputation: Sell her cartographic data and sell goods at Prospector's Rest station.
The Dweller
Wyrd Wyrd A2 Black hide
Learn about: revealed by default.
Gain access: You must do business at at least five black markets before he will see you.
Initial contract: 500,000 CR donation.
Modules / maximum level: Beam lasers , Power distributors , Pulse lasers
Short-cut to reputation: Sell goods at Black hide base.
Tod "The Blaster" McQuinn
Wolf 397 Trus Madi Trophy camp
Learn about: revealed by default.
Gain access: hand in fifteen or more bounties.
Initial contract: Bring him 100,000CR worth of bounty.
Modules / maximum level: Cannons , Fragment cannons , Multi-cannons , Rail guns
Short-cut to reputation: Hand in bounty for Alliance systems at Trophy Camp station.
Zachariah Nemo
Yoru Yoru 4 Nemo cyber party base
Learn about: reach level 3 and 33% reputation with Elivira Martuuk.
Gain access: You must then do missions for Party of Yoru in the Yoru system. Once allied with the faction, you will receive an invitation to the Engineer.
Initial contract: Zachariah requires a donation of 25T of Xihe Biomorphic Companions - get these from Xihe at Zhen Dock.
Modules / maximum level: Fragment cannons , Multi-cannons , Plasma accelerators
Short-cut to reputation: Sell goods at Nemo Cyber Party base.