12. Minimal Runtime Architecture

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12. Minimal Runtime Architecture

Dryad's runtime implements in C++ a minimal set of approximately 50 primitive syscalls (intrinsics), enabling the Standard Library to be almost 100% written in pure Dryad, facilitating self-hosting and broad debugging. All raw intrinsic calls are wrapped in safe Dryad functions that validate inputs and manage cleanup — raw intrinsics may only be used within the standard library's boundary layer. The runtime includes a native Buffer type with bounds-checked access, zero-copy I/O operations, and a Hardware Abstraction Layer (HAL) that isolates platform-specific syscall differences behind a uniform interface.

Category	Primitive Syscall	Runtime Description
File I/O	open, read, write, close, lseek, stat, unlink, mkdir	Access to direct file descriptors of the file system.
Networking	socket, connect, bind, listen, accept, send, recv	Multiplexed network configurations.
Memory	malloc, free, realloc, memcpy, memset	Internal runtime allocation with reference counting.
Async I/O	epoll_create, epoll_wait (Linux), kqueue, kevent (macOS)	OS-level event loop without thread-blocking.
Process/Thread	fork, exec, wait, pthread_create, pthread_join	Processor parallelism synchronization.

Using the Intrinsic Syscall System

 1 // Internal runtime native syscall declaration
 2 @intrinsic("syscall.open")
 3 extern function __open(path: string, flags: i32): i32;
 4 
 5 @intrinsic("syscall.read")
 6 extern function __read(fd: i32, buf: ptr8>, len: usize): isize;
 7 
 8 @intrinsic("syscall.close")
 9 extern function __close(fd: i32): void;
10 
11 // Abstract handler class in pure Dryad
12 export class Arquivo {
13   private fd: number;
14 
15   constructor(caminho: string) {
16     this.fd = __open(caminho, 0); // O_RDONLY
17     if (this.fd < 0) {
18       throw "Failed to read native file!";
19     }
20   }
21 }

The entire socket library, virtual file system, HTTP client, and JSON parser are built in pure Dryad consuming these intrinsic primitives.

Found an error in the spec? Open a PR.
Official Version: 1.0 · May 2026