GR / HOMETHE LABTRAINING / G4 / INSTRUCTION TUNING

FLAGSHIP / MACHINE INTELLIGENCE

GregRietta

I kept pulling on the question of how language models actually work until there was a tokenizer, a training loop, checkpoints, evaluation, and a model family with version numbers.

The point is not to build a tiny ChatGPT. The point is to make the abstraction disappear.

Open gregrietta.com

CURRENT GENERATION

G4 / INSTRUCTION TUNING

G4-v6 finished its full 1.63B-token pretraining run. The best checkpoint landed at step 793,750 with 2.5328 validation loss. Now that same 69.1M model is being instruction-tuned on 27,024 assistant examples so it can learn how to answer people, not just continue text.

69.1Mmodel parameters
1.63Bpretraining tokens
2.5328best validation loss
27,024instruction examples
01

WHY

Understanding beats magic.

Using a model is easy. Building one forces every hidden decision into the open: what data looks like, how text becomes tokens, what the network is allowed to remember, how optimization behaves, and how quickly a model can learn the wrong lesson.

Every answer creates three more questions.
02

THE CURRENT WORK

Pretraining finished. Now teach it to answer.

G4-v6 completed all 796,545 planned optimizer steps across the 1.63B-token training corpus. The best checkpoint came from step 793,750 at 2.5328 validation loss. That checkpoint is now the base for response-only instruction tuning across 27,024 training examples and 524 validation examples.

The model learned language first. Now it learns the assistant role.
03

WHAT I WATCH

The data got serious.

The corpus is not just a giant text pile. It pulls from broad technical, educational, reference, web, and book sources, then filters duplicates, repetition, boilerplate, and low-quality patterns before training. More data only helps if the model is learning from something worth keeping.

04

WHERE IT GOES

Measure the base model, then measure the assistant.

The completed base model already has frozen behavior benchmarks. After instruction tuning, it goes through those again plus assistant-focused tests. That comparison should show how much of the remaining weakness is model capacity and how much was simply never teaching the base model how to answer a user.

G5 waits until G4-SFT earns the next move.

PROJECT DNA

The part the README would leave out.

ORIGINI wanted to understand language models.
ESCALATIONSo I started building one.
BAD DECISIONSTraining runs at unreasonable hours.
CURRENT STATEG4 engineering foundation.

THE REST OF THE LAB

The model does not live alone.

NOWQUESTIONABLE IDEA IN PROGRESS