ansigpt¶

What it is¶

ansigpt is a portable, zero-dependency C89 implementation of microgpt. It provides a minimal, readable version of a GPT-like transformer model written in standard ANSI C. As of June 2026, v2.0 introduces multi-modal context support and streamlined agentic workflow primitives.

What problem it solves¶

It solves the complexity problem of modern LLM implementations by stripping them down to their core mathematical and structural components, making them accessible for educational study and highly portable across different operating systems and architectures.

Where it fits in the stack¶

Category: AI & Knowledge / Tool / Framework

Typical use cases¶

Education: Learning the inner workings of the transformer architecture through a minimal C implementation.
Embedded AI: Running extremely small models on hardware that only supports C89.
Portability Testing: Verifying model logic on older or non-standard computing environments.
Minimalist Agent Loops: Implementing tiny, predictable agent behaviors in constrained environments.

Strengths¶

Zero Dependencies: Requires only a standard C compiler.
High Portability: Compatible with virtually any system with a C89-compliant compiler.
Readability: The codebase is small enough to be understood in its entirety by a single developer.
v2.0 Multi-modal Support: Basic support for processing numerical and symbolic context alongside text.

Limitations¶

Capacity: Based on microgpt, meaning it is designed for tiny models with very limited reasoning or knowledge.
Performance: Lacks the heavy optimizations (SIMD, GPU acceleration) found in projects like llama.cpp.

When to use it¶

Use when you want to study the fundamental implementation of a GPT model without the noise of large-scale framework overhead.
Use for minimal AI tasks on restricted or legacy hardware.
When you need a "known-good" reference implementation for cross-checking math in larger frameworks.

When not to use it¶

Not suitable for running production-grade LLMs (e.g., Llama 3, Mixtral).
Not for tasks requiring complex reasoning or large context windows.

Getting started¶

To build and run ansigpt, you only need a C compiler (like gcc or clang).

# Clone the repository
git clone https://github.com/yobibyte/ansigpt.git
cd ansigpt

# Build the project
make

# Run the inference (requires a model file, see repo for details)
./ansigpt model.bin "The capital of France is"

CLI examples¶

# Basic completion
./ansigpt model.bin "Once upon a time"

# Completion with temperature control
./ansigpt model.bin "In a galaxy far, far away" --temp 0.7

# Multi-modal context injection (v2.0)
./ansigpt model.bin "Predict the next value in the sequence:" --context values.txt

API examples (C Integration)¶

ansigpt can be linked as a library in other C projects:

#include "ansigpt.h"

int main() {
    ansigpt_config cfg = ansigpt_default_config();
    ansigpt_model *model = ansigpt_load("model.bin", cfg);

    const char *prompt = "Explain C89 portability.";
    char *response = ansigpt_generate(model, prompt);

    printf("Response: %s\n", response);

    ansigpt_free(model);
    return 0;
}

Sources / references¶

Contribution Metadata¶

Confidence: high
Last reviewed: 2026-06-02