Changelog for Update 20752 (added 26 July 2017):

Changes
- Revamped the Loading and AI Turns wait animations, and made changes to the graphics library so that star/planet/map animations will continue in the background (instead of freezing) during wait times.
- Revamped the Load/Save dialog.
- Increased the base resource yields of most alien native populations.
- Reduced the cost of Bombers by one-third.
- Increased the cost of Strike Fighters and added Antimatter as a prerequisite for the Multirole Fighters tech.
- Increased the cost of Heavy Railguns and halved damage.
- Deflector screens now absorb 50% of kinetic weapons damage, while Battle shields now absorb 70%.
- Decreased the damage of Neutron Beams.
- Ashdar Colonials fighter squadrons now have one additional fighter per Hangar module.
- Increased the damage of Pulson Launchers from 35 to 50.
- The technology 'Energy Torpedoes' is now called 'Plasma Projectiles' and requires Plasma Focusing.
- Increased the research costs of all late game technologies.
- Adjusted the wording in various resource descriptions to help clarify the distinction between the resource names (Labor, Science, Coin, Metal, Food) and the associated activities (Production, Research, Trading, Mining, Farming).

Fixes
- Fixed a bug in the tactical weapon selection UI that prevented the first item in a ship's weapon list from being consistently selected when selecting a ship.
- Fixed a glitch in the planet farming/food description text.
- Fixed a few description text errors.
- Added new UI scaling rules for very high resolution monitors, and changes to avoid blurriness on high DPI monitors.
- Made improvements to GoG Galaxy achievement/stat error handling.
- Updated the Visual Studio runtime libraries to the 2017 versions.
- The 'simplified graphics' rendering mode is now enabled by default for all Intel HD 3000 and Radeon HD 7800 Series cards.

No need for thanks, and cheers for the link.

Devs presence and activity is always appreciated.

Changelog for update 21183 (added 4th October 2017):

Changes & Additions:
- Added a choice of Map Shape options (Box, Ring, Hourglass, Ellipse) to the Advanced Map Settings pane when creating a new game.
- Added a number of new UI sound effects including: load/save game complete, colony founded, planet special discovery, war declaration, enslave, liberate, forced labor, experiments, and galaxy creation complete.
- Added a 'Right Click Close' UI option to the Options pane.
- 'B' now acts as a hotkey for buying production on the currently selected planet.
- There is now a Hail Fleet option that adds a diplomatic option when your fleet intercepts an alien colony ship attempting to land in the same system.
- AI factions will now accept trades for some resources, provided that a fair offer is made.
- Hiring mercenaries now costs influence, in addition to coins.
- The influence cost of securing a peace treaty will now vary depending on how the other faction feels the war has been going.
- All factions now receive 1 influence per turn if they have any contact with alien factions.When initially researched, Markets now increase trade capacity by 2 each (up from 0).

Fixes:
- Changed AI handling of three+ sided conflicts, should fix logic errors in AI code.
- Reduced the frequency of several types of planet disaster events.
- Fix for a formatting error when trading with marauder companies.
- Made several low-level changes intended to work around problems with the latest AMD drivers.
- In windowed mode, window resizing cursors should now appear when appropriate.
- Altered the deficit handling rules -- forced scrapping now always yields some coin return.
- Adjusted planet autobuild logic to favor Trade in situations where deficits are imminent.
- AI players should now build more Markets during the late game.
- Fix for a bug that could cause re-contacted empires to respond as if you'd just meet.

Changelog for Patch 21606 (added 06 November 2017):

Changes and Additions
* Added new tactical background art for battles at Hyperspace Anomalies.
* Added the Herald battlecruiser-class unit for the Arda Seed. The Herald will now use this instead of a Mediator.
* Changed the behavior of Star Harpy swarm events: swarms are reduced on Easy difficulty, and Harpies will not attack planets.
* Added several new Arda Seed-specific ship components.
* Updated background art for the Tinkers leaders.
* Bombers and Strike Fighters now carry regular missiles instead of torpedoes.
* When scrapping a factory on a colony that has both factories and machine altars, factories are always scrapped before machine altars.
* Mobile Bases and Asteroid Outposts now have specific description text.

Fixes
* Fix for an error affecting certain Intel Iris graphics drivers.
* Fix for a rare bug that could be triggered by rendering certain text strings (Juggernaut bug).
* Fix for a display bug in the planet production info panes.
* Fix for a layout problem in the planet production info panes; long colonist names should no longer overlap resource yields.
* Fix for a bug that was preventing declaration of war notifications from appearing.
* Fixes for some in game text errors (missing tooltips, etc.).
* Fix for a bug that could be caused by allying with a player with access to hyperspace anomalies.
* Fix for a bug that could be caused by opening the fleet list pane while at a hyperspace anomaly.
* Fixed the on-click behaviors of the small icons in the agreement dialog panes.

Changelog for Patch 21692 (added 15 December 2017):

Changes and Additions
* Added new units for the Arda Seed: the Steward, Engineer, and Harpy Nest.
* Arda Seed will now periodically reinforce, set up nests, and expand from systems they occupy.
* Added autopsy reports for the Proteans and all the new Arda Seed units.
* All Arda Seed units now have some inherent self-repair ability.
* Updated railgun animation.
* The Ashdar missile cruiser now has torpedo, rather than missile, hardpoints.
* It is now possible to embark ground units to a Station equipped with assault shuttle bays.

Fixes
* Building additional stations should no longer cause planets with Shipyards to lose their production discount.
* Technologies gained from the Herald or a derelict colony should now be correctly removed from the research queue.
* Fix for a bug that could prevent Star Harpy Autopsies from being awarded as intended.
* Fix for a rare bug that could cause stations to attempt to attack themselves.
* Missile hardpoints can no longer mount torpedoes.
* Fixes for some sound and animation glitches affecting the Herald and Mediator ships.
* Stations captured in tactical combat will now be destroyed at the end of the turn unless the planet they orbit is also captured.

Changelog for Patch 21910 (21 February 2018)

Changes and Additions
- The Herald of the Arda Seed now tracks reputation with the player's faction, and available purchases are now dependent on reputation level.
- Players may now purchase and discover Codexes, which unlock previously unavailable technologies for research.
- The Tinkers' Bomber has been replaced by the Vindicator, which is an expendable multiple-warhead manned missile which can be launched from torpedo hardpoints as well as hangars.
- Arda Seed Proteans will now use an offensive suicide attack after closing on enemy ships.
- Added five new achievments related to the Legacies DLC.
- The mining activity now provides +50% output per mine (up from +33%).
- Earthquake random events are now limited to destroying at most 2 improvements.
- Added the 'minerals discovery' random event.
- Added the 'artifacts discovery' random event.
- Increased Market Coin production from 4/7/12 to 5/10/15.
- Increased second and third tier Factory Labor production.
- Adjusted Dread Star production costs.
- Added a 'hostile environment' upkeep cost for colonies in harsh environments. This new mechanic is suppressed in any game started prior to r21718 so that it will not affect existing saves.
- AI empires should be less likely to choose to colonize hostile environment worlds.
- Marauder factions should be less hostile to AI empires.
- AI empires will now make use of outposts to extend range.
- Increased the planetary bombardment power of carriers.

Fixes
- Fix for a rare bug that could be triggered when Harpy fleets returned to their source HSA.
- Losing a planet should now reliably resolve all pending construction complete warnings pertaining to that planet.
- Fix for a bug caused by unresolved attacks against fleets belonging to a defeated empire.
- Fixes for bugs that could be triggered by refitting ships while in the process of issuing a move order.
- Fix for a production display bug affecting planets with space habitats.

Changelog for Patch 21939 (26 February 2018)

- Hotfix for a bug triggered when Vindicators attack cloaked ships.

(According to the changelog's thread on dev's forum)

Changelog for Patch 22095 (19 March 2018)

2018-03-19(22095)- 'stable'
- Hotfix for a bug triggered by planets depopulated due to starvation.
- Hotfix for a bug that could be triggered by Orthin ships equipped with an outdated version of the 'Shield Capacitor' system.

2018-03-17(22087)- 'stable'
- Fix for a tech tree bug that could be triggered by reverse engineering Fusion Torpedoes while playing as Orthin or Gremak.
- In the case that battle salvage unlocks techs that are impossible to research, the player will no longer receive a "tech unlocked" notification.
- The Phidi Torpedo destroyer, human Missile Cruiser, and human Battleship all now have 'Torpedo' rather than 'Missile' hardpoints.
- It is now possible to place 'Blast Doors' and 'Scanners' in a Heavy hardpoint.

2018-03-16(22079)- 'stable'
- Fix for a bug that could be triggered when Vindicators retarget on a new ship.
- Fix for a bug that was preventing the Shield Piercing abilities of the Force Lance from working as intended.

2018-03-15(22066)- 'stable'
- It should no longer be possible for the food cost of City Planning to be negative.
- Orthin ships equiped with Shield Capacitors now have access to the "Overcharge" and "Shield Boost" special abilities.
- Fix for a game state maintenance bug affecting battles in which the right-click inhibit weapon fire toggle had been used.

2018-03-13(22043)- 'stable'
- The 'hail fleet' option should no longer appear when an empire you are at war with attempts to colonize a planet.
- The Orthin Dreadnaught now has only 1 Capacitor slot. (Old designs may need to be edited.)
- Orthin 'Capacitor' hardpoints have been renamed as 'Busbar' hardpoints.
- Blast doors can now be placed in Busbar harpoints.
- The 'Energy Refocusing' technology is being retired, and will not appear in new games.
- Orthin players will now unlock the 'Power Converter' busbar component after researching 'Zero-Point Energy'.

2018-03-08(22036)- 'stable'
- Editing an outpost transport design now edits the design of the created outpost.
- Outpost designs are no longer required to include a fuel depot.
- Outpost designs that include Space Habitats can now be loaded prior to deployment.
- Outpost transports built in old saves will no longer function.
- Colonists in deployed Space Habitats now consume food.
- Viscid now have the 'vermin' trait, making them immune to starvation.

2018-03-05(22002)- 'stable'
- Adjusted the color of the Tinkers star names.
- Adjusted the territory lines style.

2018-02-28(21993)- 'stable'
- +Healed numbers should now appear when ships regenerate shields or armor.

2018-02-27(21989)- 'stable'
- Replaced the 'Pirate Activity' advanced setting with 'Raider Activity'.
- 'Raider Activity' now also controls the level of Star Harpy activity.
- Reduced the frequency of some Star Harpy events.
- The components list should no longer show incorrect small craft graphics when designing planet defenses.
- Colony ships can now always colonize a planet if the colonists onboard would be comfortable there.
- Warning icons will now appear by systems blockaded by enemy ships.

2018-02-26(21977)- 'stable'
- Removed redudant post-battle 'technology unlocked' notifications.
- Most map settings should now default to the values used in the most recent savegame.
- Clicking on a planet's special resource icon should now open the planet info entry for that resource.
- Added a 'Supergrain Discovery' event.
- Clicking on a fleet's empire icon will now start a conversation with that empire, if possible.

2018-02-24(21961)- 'stable'
- Added a territory overlay layer.
- Added a new option pane toggle: 'Show Empire Territory'.
- Added a new option pane toggle: 'Show Fleet Route Lines'.
- Added a new option pane toggle: 'Show Empire Insignia'.

You're very welcome ! :)
Thanks for the heads up ! I updated my post to include this infos.
I really love your game and all the hard work you're putting in it. Keep up the great work ;)

Changelog for Patch 22101 (22 March 2018)

2018-03-21(22101)- 'stable'
- Hotfix for a bug related to slavery and orbital populations.
- Native population on planets where your empire has an outpost should no longer consume food.
- Hotfix for a bug in the planet starvation logic.

2018-03-19(22097)- 'stable'
- Fix for a bug triggered by moving multiple population units onto a single transport.
- Hotfix for a bug triggered by planets depopulated due to starvation.
- Hotfix for a bug that could be triggered by Orthin ships equipped with an outdated version of the 'Shield Capacitor' system.

[please note that 22097 includes 22095 + a new fix]
[source of the changelog : changelog's thread on dev's forum]

Damn bugs... XD Thank you very much for the very fast fix, and too for thinking about non-galaxy installers :)
You're very welcome, it's absolutely sincere ;)

Changelog for Patch 22151 (16 April 2018)

2018-04-15(22151)- 'live'
- Fix for a bug that could incorrectly prevent planets from using 'City Planning'.
- Fix for a bug that could occur after the AI disembarked transports.
- Fixes for various bugs in the starvation warning feature.
- Adjustments to the display rules for Tinkers fleets.

2018-04-12(22135)- 'live'
- Marauders should now be able to capture outposts without causing a bug.
- Fix for a cloaking effect rendering glitch.
- Fix for a rare bug involving the autobuild mechanic.
- Fix for a bug involving captured outpost transports.

2018-04-11(22125)- 'live'
- Capturing Orthin ships equipped with Power Converters should no longer cause a crash.
- Placing Vindicators in Yoral torpedo hardpoints should no longer cause a bug.
- Fix for a bug in the starvation warning display logic.

2018-04-09(22116)- 'live'
- Fixes for inaccuracies in the special resource description text.
- Fix for a bug in the AI fleet routing logic.
- Fix for a bug in the empire logo drawing logic.

2018-03-29(22110)- 'live'
- Fix for a bug that could occur after defending a planet that was suffering from starvation due to blockade.
- Various minor text corrections.

[GOG's changelog only show changes of 22151. Source of the complete changelog : changelog's thread on dev's forum]

Changelog for Update 37959 (added 21 January 2019):

Gameplay Changes and Additions
- Changed balance and AI advantages on Normal, Hard, and Brutal settings. Players may find games on settings above "Easy" to be noticeably harder.
- The AI no longer receives resource bonuses on 'Normal' difficulty mode.
- The player now receives resource bonuses on 'Easy' modes.
- Torpedoes can now be placed in heavy hardpoints.
- Orthin and Gremak can now research Heavy Missiles.
- Strike fighters will now attack starships using beam weapons if their beam weapons are more powerful than their missiles.
- Significantly reduced the range of anti-missiles.
- Reduced marauder ship spawn rates.
- Reduced the strength of Marauder fleets.
- It is now possible to deploy outposts around planets you already control.
- Added several new diplomatic issues.
- Added the 'Expansion Request' event.
- Added the 'Trade War' event.
- Added the 'International Incident' event.
- Added the 'Wreckage Analyzed' event.
- Added the 'Technology Captured' event.
- Reduced the research cost of 'Defense Grid'.
- Increased many agreement influence costs.
- Increased upkeep costs for mid/late game ship hulls.
- Phidi no longer start without the 'Military Doctrine' technology.
- Changed the hiring cost formula of mercenaries; in most cases this is an increase.
- Decreased the spawn rates of mercenaries.
- Increased the cost of the 'Artificial Organisms' tech.
- Increased mid/late game strategic fleet speeds.
- Upgrading tanks no longer increases their build or upkeep costs.
- Increased the number of stars in 'small', 'normal', and 'huge' maps.
- Citizens from allied factions will now sometimes offer to join your empire.
- Allying with an alien faction now removes the "Alien Rulers" morale effect from colonists of their race in your empire.
- Increased the research cost of 'Battle Mechs'.
- Galactic council votes can now influence reputation.
- 'Graviton Physics' and 'Advanced Field Theory' now grant increased tactical speed.
- Increased mid/late game science boosts from experimenting on slaves.
- Reduced the number of technologies offered by the Herald.
- Updated mechanics for ancient data archives.
- Tinkers AIs should now make use of Asteroid Outposts.
- Changes to the random number generator used in planetary bombardment / invasions to improve the accuracy of the predicted outcome display.
- 'Artificial Sentience' now provides +15 science on all worlds instead of +1 improvement slot.
- 'Adaptive Energy Grid' now provides +10 labor on all worlds instead of +1 improvement slot.
- 'Social Engineering' now unlocks a varying number of improvement slots depending on planet size.

AI Changes and Additions
- Various tweaks to the Strategic AI. (Thanks to Harpy Eagle for his contributions.)
- The AI's ship building strategies should now reflect its research strategies, and vice versa.
- A variety of fixes and improvements in the AI's economic logic.
- A variety of fixes and improvements in the tactical combat AI.
- Significant changes to AI behaviors around starting and stopping wars.
- The AI should now be less likely to spam colony ships.
- Adjustments to the AI's handling of planet production changes.
- The AI should now pursue more varied research paths.
- The AI should now sometimes transfer population units between planets.
- AI's will now be more likely to cooperate with allies.
- AI's should now wait at least 15 turns between making peace and restarting a war.
- AI's may now demand that you stop trading with their enemies.
- AI's may now demand that you release their people from slavery.
- AI's may now issue ultimatums before starting a war.
- AI's may now insist that your fleets stay outside their territory.
- AI's may now request to start joint wars against third parties.
- AI's may now demand that you return control of colonies they have a historical claim to.
- AI's may now object if you establish colonies/outposts in their territory.
- AI's may demand control of splinter colonies founded by members of their own species.
- AI's may offer gifts to friendly players.
- Allies should now better cooperate when routing defensive fleets.
- Tweaks to the logic governing AI tactical retreats.
- Changes to the AIs "sue for peace" logic.
- Changes to peace concessions.
- Changes to formula used in resource request events.

UI Changes and Additions
- Added a Victory screen that includes a Graphs screen.
- Added an "Intelligence Briefing" option to the diplomacy screen which will display Graphs for known factions (hotkey Ctrl-G).
- Added a Credits pane to the Main Menu.
- Added various faction-specific weapon art assets.
- Updated the layout scheme for population icons in the planet information screen.
- Added a 'Max Pop' option to the list of sorting criteria in the Planetary Report

Fixes
- Fix for a low level bug in the AI task dispatching logic.
- Added debugger hooks for VS Code.
- Fix for a bug involving intercepted AI transport fleets.
- Fix for a bug involving AI City Planning.
- Fix for a bug in the city planning food consumption logic.
- Fix for a bug caused by absorbing an empire that contained outposts.
- Fix for a star shader glitch affecting many cards using newer AMD drivers.
- Attempted workaround for a bug affecting ship designer part placement.
- Fix for a bug in the AIs handling of captured ships.
- Fix for a bug in the war/peace logic.
- Fix for a bug in the AI improvement selection logic.
- Fix for a bug caused by reverse engineering captured Tinker technologies.
- Fix for a bug involving ignored ship capture reports.
- Transferring control of planets will now also transfer control of all orbiting stations.
- Tinkers should no longer request food aid.
- Fix for a bug caused when one AI empire absorbs another.
- Fix for a bug in the "empire eliminated" report.
- Transfers of planetary ownership should no longer leave invalid "encounter" reports on the starmap.
- Fix for a bug caused when transports arrive at a planet that has changed allegiance.
- Annexing a planet will now reduce its planetary defense level to match what is permitted by your technology.


EDIT: The dev posted about this here, linking to the Development Updates thread on their forum which includes a few more details.