Building an LLM From Scratch

📰 Medium · AI

Learn how to build an LLM from scratch by following a project that mirrors GPT-1 and discover the challenges and solutions encountered along the way

advanced Published 13 Jul 2026

Action Steps

Investigate the architecture of GPT-1 and its components
Mirror the GPT-1 model and identify potential issues
Explore alternative datasets to BookCorpus for training the LLM
Implement and test the LLM model using the chosen dataset
Evaluate the performance of the LLM model and compare it to GPT-1

Who Needs to Know This

This project is relevant to AI engineers, researchers, and developers who want to understand the process of building a large language model from scratch. It can help teams working on NLP projects to learn from the experiences and challenges faced by the authors.

Key Insight

💡 Building an LLM from scratch requires careful investigation of the model architecture, dataset selection, and performance evaluation

Key Takeaways

Learn how to build an LLM from scratch by following a project that mirrors GPT-1 and discover the challenges and solutions encountered along the way

Full Article

Title: Building an LLM From Scratch

URL Source: https://medium.com/@kosiashara/building-an-llm-from-scratch-96501dcf163a?source=rss------artificial_intelligence-5

Published Time: 2026-07-13T23:53:57Z

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1. [This is Part 1 of a series documenting a project to build an LLM from scratch, mirroring GPT-1, with Kingsley Nworie, Abdullahi Mujaheed Aliyu, and Ayeni Oluwatosin Olawale. Code is here: github.com/thekingslee/build-an-llm.](https://medium.com/?source=-----96501dcf163a---------------------------------------#377d "This is Part 1 of a series documenting a project to build an LLM from scratch, mirroring GPT-1, with Kingsley Nworie, Abdullahi Mujaheed Aliyu, and Ayeni Oluwatosin Olawale. Code is here: github.com/thekingslee/build-an-llm.")
2. [The project, and why I joined it](https://medium.com/?source=-----96501dcf163a---------------------------------------#dc5f "The project, and why I joined it")
3. [Before I joined: mirroring GPT-1 and where it broke](https://medium.com/?source=-----96501dcf163a---------------------------------------#5577 "Before I joined: mirroring GPT-1 and where it broke")
4. [The investigation](https://medium.com/?source=-----96501dcf163a---------------------------------------#2d55 "The investigation")
5. [My contribution: investigating the BookCorpus and finding an alternative](https://medium.com/?source=-----96501dcf163a---------------------------------------#8813 "My contribution: investigating the BookCorpus and finding an alternative")
6. [What’s next](https://medium.com/?source=-----96501dcf163a---------------------------------------#5fd8 "What’s next")

# Building an LLM From Scratch

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[Kosi Ashara](https://medium.com/@kosiashara?source=---byline--96501dcf163a---------------------------------------)

8 min read

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Building an LLM From Scratch

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