Announcement
CorX Labs releases CorX1.5, an open-source language model built from scratch in Jamaica.
Jamaica · · For immediate release
CorX Labs, an independent artificial intelligence research lab and research station based in Jamaica, today announced the open-source release of CorX1.5 — a 158-million-parameter language model designed and trained entirely from scratch by a single developer on a single GPU.
CorX1.5 is not a fine-tune of an existing base model. Its architecture, its 32,768-token tokenizer, its pretraining pipeline and its fine-tuning were all written in house and trained from random weights. The model is a custom decoder-only transformer using RoPE positional encoding, SwiGLU feed-forward layers and RMSNorm, with 10 layers and a 1,024-token context window, and it introduces learned role embeddings — a signal that marks every token as user, assistant or raw text at the architecture level, rather than leaving the model to infer it from special tokens.
Training ran in three stages: pretraining on approximately 3 billion tokens drawn from
25 open datasets spanning code, mathematics, reasoning, conversation and general text;
distillation from a larger teacher model with automated quality filtering; and reasoning
training, in which the model learns to show its working inside
<think> blocks before answering. A held-out validation split with
early stopping was used throughout.
The lab is publishing the model with an explicit statement of its limits. CorX1.5 is a small model trained on billions of tokens where comparable models from major labs are trained on trillions, and CorX Labs states plainly that it is not suitable for broad factual recall, complex multi-step mathematics, or production and safety-critical use. The model also ships with a hardcoded crisis-response layer, implemented in code rather than left to the model's judgment.
“For years I've shared a dream to build something great — my own AI. Today that dream came through, and I can say I made it from scratch, from the ground up.”
Nathan, founder of CorX Labs
Availability. CorX1.5 is available now under the Apache 2.0 licence on Hugging Face at huggingface.co/Sigmandndnns/CorX1.5-160M, including weights, tokenizer and the model definition required to load it. Training is ongoing, with updated checkpoints released as new data is added.
About CorX Labs. CorX Labs is an independent AI research lab and research station in Jamaica, in the Caribbean. It designs, trains and open-sources language models built from the ground up. Media and business inquiries: lkk89002@gmail.com.