Stof vs. WebAssembly

TL;DR

• WebAssembly (wasm) is a portable binary instruction format for executing compiled code at near-native speeds

• Stof is a text-based executable data format designed for sending logic + data together over APIs

Key difference: Wasm is optimized for performance. Stof is optimized for portability, flexibility, inspectability, and lightweight transmission.

Stof is written in Rust and compiles to WebAssembly so that it can be embedded where you work.

Comparison

Both let you:

• Execute code in a sandbox

• Run the same logic across different platforms

• Provide security boundaries for untrusted code

• Embed executable logic in different environments

Feature	WebAssembly	Stof
Primary use case	High-performance computation	Executable data interchange
Format	Binary (.wasm)	Text (.stof) or Binary (.bstf)
Typical size	100KB - 10MB+	1KB - 100KB
Over-the-wire	❌ Too large for most APIs	✅ Designed for it
Inspectability	❌ Lots of additional tooling	✅ Human-readable/insepectable
Data + logic together	❌ Separate	✅ Unified document
Execution speed	✅ Near-native	🟡 Interpretted (slower)
Startup time	🟡 Instantiation overhead	✅ Fast
Browser support	✅ Native	✅ Runtime as Wasm
Tooling maturaty	✅ Mature (lots of tooling)	🟡 Growing
Best for	Entire apps, games, crypto	Configs, workflows, APIs, distributed systems, data interchange, open protocols, etc.

The Core Use Case Difference

WebAssembly:

"Compile performance-critical code once, run it anywhere fast."

Use when you need computation speed (games, image processing, cryptography).

Stof:

"Send lightweight executable data that describes both what and how."

Use when you need to transmit logic + data together (APIs, configs, workflows).

---

Size Comparison: The Big Difference

This is where the distinction becomes critical.

WebAssembly:

// Compiled from Rust
fn hello() -> String {
    "Hello, World!".to_string()
}

Binary size: ~1.8MB (including Rust std) Stripped binary: ~150KB With wasm-opt: ~20KB

---

Stof:

fn hello() -> str {
    "Hello, World!"
}

Size: 67 bytes

Task	Wasm Size	Stof Size	Ratio
Hello World	20KB	67 bytes	300x smaller
Simple math	25KB	150 bytes	170x smaller
String manipulation	180KB	400 bytes	450x smaller
JSON transformation	500KB	2KB	250x smaller
API validation	1.2MB	5KB	240x smaller
Complex workflow	2.5MB	15KB	170x smaller

Average: Stof is 200-300x smaller for typical API/config use cases

Summary

Use WebAssembly when:

• You need maximum computation speed (games, video, crypto)

• You're processing large amounts of data locally

• Binary size doesn't matter (desktop apps, embedded systems)

• You need access to existing C/C++/Rust libraries

• Performance is more important than inspectability

Use Stof when:

• You need to send logic over APIs (size matters)

• You want human-readable, inspectable code

• You need data + logic in one document

• Fast cold starts matter (serverless, edge)

• You're building configs, workflows, or data pipelines

• Inspectability and security auditing are important

Use both when:

• You need Stof for orchestration + Wasm for heavy computation

• You want lightweight transmission (Stof) with performance-critical sections (Wasm)