Crate aether_core 

aether-core

Hard real-time modular DSP engine — lock-free graph scheduler, generational arena, and zero-allocation buffer pool.

64-sample buffer | 48 kHz | ≤1.33 ms deadline | Zero allocations | Lock-free

Architecture

Control thread                    RT audio thread
──────────────                    ───────────────
AudioGraph (add/remove nodes)     Scheduler::process_block()
    │                                 │
    │  CommandRing (SPSC)             ├─ drain CommandRing
    └────────────────────────────────►│
                                      ├─ iterate sorted NodeArena
                                      ├─ borrow buffers from BufferPool
                                      └─ call DspNode::process() per node

Real-time guarantees

Rule	Enforcement
No heap allocation	Pre-allocated arena + buffer pool
No locks	SPSC ring buffer (ringbuf)
No I/O	All I/O on control/tokio threads
Bounded execution	Flat topo-sorted array, ≤32 commands/tick

Quick start

See node::DspNode to implement a processing node, [graph::AudioGraph] to build a patch, and scheduler::Scheduler to drive the RT loop.

Modules

arena

Generational arena allocator.

buffer_pool

Pre-allocated audio buffer pool.

command

Lock-free command protocol between the control thread and the RT audio thread.

graph

Directed Acyclic Graph (DAG) for DSP routing.

hotreload

Hot reload support for DSP nodes.

node

Node abstraction for the DSP graph.

param

Sample-accurate parameter automation.

preset

Preset system for saving and loading DSP graph configurations.

scheduler

Real-time audio scheduler.

schema

JSON Schema validation for presets and configurations.

state

State continuity framework.

Constants

BUFFER_SIZE

Audio buffer size in samples. Hard real-time constraint: 64 samples @ 48kHz = 1.33ms deadline.

COMMAND_RING_CAPACITY

Command ring buffer capacity.

MAX_BUFFERS

Maximum number of audio buffers in the pool.

MAX_COMMANDS_PER_TICK

Maximum commands processed per audio callback. Bounds mutation cost.

MAX_INPUTS

Maximum number of inputs per node. Kept small to fit in cache lines.

MAX_NODES

Maximum number of nodes in the arena. Pre-allocated at startup.