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Next-gen zero-allocation packet framework for Paper 1.21+. High-performance Kotlin alternative to ProtocolLib.

Report Slipstream?

Release
v2.0.0

ClCody released Slipstream version v2.0.0 on June 4, 2026

๐Ÿš€ Slipstream Engine v2.0.0: The Type-Safe & Zero-Allocation Update

We are thrilled to announce Slipstream v2.0.0, our biggest architectural update yet. This release completely transforms how developers interact with NMS packets, introducing an elegant, 100% type-safe API with absolutely zero runtime overhead.

โœจ Key Features & Major Changes
  • ๐Ÿ—๏ธ Multi-Module Architecture & Code Generation Slipstream now dynamically scans NMS classes during compilation to generate over 500+ highly optimized @JvmInline value class wrappers. This isolates the core logic from Minecraft internals and guarantees compatibility.
  • ๐Ÿ›ก๏ธ The wrapAs<T>() Revolution We replaced the global Any.isPacket() extensions with a single, elegant wrapAs<T>() inline function. It uses Kotlin's reified types to cast packets safely in one line:
    packet.wrapAs<WrapperServerboundMovePlayerPacket>()?.let { move ->
        println("Player moved to ${move.pos.x}")
    }
    
    Zero overhead, zero global namespace pollution.
  • ๐Ÿ“ฆ Zero-Allocation Nested Structures Our value-class wrappers now extend to internal NMS types! Methods returning BlockPos, Vec3, or ItemStack now return generated WrapperBlockPos and WrapperVec3 instead of raw Any. No heap allocations, maximum speed.
  • ๐Ÿ’พ Java Records Support (1.20+) Modern Minecraft packets are heavily based on Java Records. Slipstream now natively supports them. Instead of setters, immutable packets now receive a .copy() method (just like Kotlin data classes) powered by cached MethodHandles.
  • ๐Ÿช„ Mutable Setters For legacy/mutable packets, we automatically generate high-performance setters using MethodHandles.lookup().unreflectSetter().
๐Ÿ“š Documentation Update

The entire project documentation has been rewritten from scratch. Check out the updated API Guide and Architecture Breakdown on our GitHub repository.

๐Ÿ› ๏ธ For Plugin Developers (JitPack)

Using Slipstream as an API has never been easier. Thanks to the multi-module setup, you only need to depend on the core module; all generated wrappers are pulled automatically:

implementation("com.github.ClCody.Slipstream:slipstream-core:2.0.0")

Information

Published onJune 4, 2026
Downloads1

Platforms

Paper Paper (1.21-1.21.11)