A light oldschool-style technology modpack with the goal of being challenging.

Progress by crafting new electrical tools and machines.
Custom crafting recipes, vanilla items untouched.
Challenging and interesting gameplay, focused on tech and exploration.
No magic mods
Build massive and complex nuclear reactors, but be careful.
No overpowered loot boxes just laying around, work your way to the riches.
Mine large areas by crafting fun quarries to mine for you. Exploit the nature as you like.
Optimized performance, quality over quantity and regular updates and fixes.

IC2 Classic for technology and power generation.
Applied Energistics 2 for mass storage.
RFTools for custom dimensions and power generation.
YUNG's revamped vanilla caves and structures for exploration.
And many more...

Full mod list:

SwingThroughGrass (by exidex)
YUNG's Better Ocean Monuments (Forge) (by YUNGNICKYOUNG)
YUNG's Better End Island (Forge) (by YUNGNICKYOUNG)
Dark Mode Everywhere (by Buuz135)
Storage Drawers (by Texelsaur)
AttributeFix (by DarkhaxDev)
McJtyLib (by McJty)
Patchouli (by Vazkii)
Ender Storage 1.8.+ (by covers1624)
Sophisticated Backpacks (by P3pp3rF1y)
Xaero's Minimap (Fair-play Edition) (by xaero96)
RFTools Base (by McJty)
Puzzles Lib [Forge & Fabric] (by Fuzs)
FastSuite (by Shadows_of_Fire)
Legendary Tooltips [Neo/Forge] (by Grend_G)
YUNG's Better Dungeons (Forge) (by YUNGNICKYOUNG)
Ding (Forge) (by iChun)
Sophisticated Core (by P3pp3rF1y)
The One Probe (by McJty)
RightClickHarvest (by jamalam360)
Placebo (by Shadows_of_Fire)
YUNG's API (Forge) (by YUNGNICKYOUNG)
Ores Above Diamonds (by Squidsword)
Better Advancements (by way2muchnoise)
Packing Tape (by gigaherz)
Animal Feeding Trough [Fabric | Forge | Quilt | NeoForge] (by Slexom)
CodeChicken Lib 1.8.+ (by covers1624)
Starlight (Forge) (by Spottedstar)
Additional Enchanted Miner (by Kotori316)
Project Red - Integration (by MrTJP)
Curios API (Forge/NeoForge) (by TheIllusiveC4)
Prism [Neo/Forge] (by Grend_G)
Controlling (by Jaredlll08)
BetterF3 (by cominixo)
Enchantment Descriptions (by DarkhaxDev)
Scalable Cat's Force (by Kotori316)
RFTools Dimensions (by McJty)
Konkrete [Forge/NeoForge] (by Keksuccino)
Entity Culling Fabric/Forge (by tr7zw)
FerriteCore ((Neo)Forge) (by malte0811)
Balm (Forge Edition) (by BlayTheNinth)
Xaero's World Map (by xaero96)
Project Red - Transmission (by MrTJP)
Project Red - Core (by MrTJP)
YUNG's Better Nether Fortresses (Forge) (by YUNGNICKYOUNG)
YUNG's Better Strongholds (Forge) (by YUNGNICKYOUNG)
Just Enough Items (JEI) (by mezz)
Drippy Loading Screen (by Keksuccino)
Bookshelf (by DarkhaxDev)
CB Multipart (by covers1624)
iChunUtil (by iChun)
Not Enough Recipe Book [NERB] (by SSKirillSS)
Snow Under Trees (by bl4ckscor3)
Easy Anvils [Forge & Fabric] (by Fuzs)
ModernFix (by embeddedt)
Better Statistics Screen (by TheCSDev)
FancyMenu (by Keksuccino)
IC2C UU-Matter (by Christofmeg)
RFTools Power (by McJty)
Iron Chests (by ProgWML6)
YUNG's Better Witch Huts (Forge) (by YUNGNICKYOUNG)
Cloth Config API (Fabric/Forge/NeoForge) (by shedaniel)
IC2 Classic (by sfPlayer1)
AppleSkin (by squeek502)
Bad Wither No Cookie - Reloaded (by Kreezxil)
Architectury API (Fabric/Forge/NeoForge) (by shedaniel)
Let Me Despawn (by frikinjay)
Mouse Tweaks (by YaLTeR)
Melody (by Keksuccino)
CraftTweaker (by Jaredlll08)
YUNG's Better Desert Temples (Forge) (by YUNGNICKYOUNG)
Project Red - Illumination (by MrTJP)
Lazy DataFixerUpper(LazyDFU) [FORGE] (by Corgi_Taco)
YUNG's Better Jungle Temples (Forge) (by YUNGNICKYOUNG)
Inventory Sorter (by cpw)
Yeetus Experimentus (by Sunekaer)
Light Overlay (Rift/Forge/Fabric) (by shedaniel)
KleeSlabs (by BlayTheNinth)
The Lost Castle (by jack_bagel)
Clumps (by Jaredlll08)
Comforts (Fabric/Forge/Quilt) (by TheIllusiveC4)
Fast Leaf Decay (by olafskiii)
Applied Energistics 2 (by thetechnici4n)
Just Enough Resources (JER) (by way2muchnoise)
Configured (by MrCrayfish)
YUNG's Better Mineshafts (Forge) (by YUNGNICKYOUNG)
Iceberg [Neo/Forge] (by Grend_G)

Classic Tech Pack