harvard-edge/cs249r_bookPublic

Machine Learning Systems

AI summary: The open-source textbook and courseware for Harvard's CS249r: Machine Learning Systems, covering edge ML to cloud infrastructure.

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PythonOtherCreated Sep 6, 2023Last push todayLatest release tinytorch-v0.1.13+131 stars this week+160 this month

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since Sep 17, 2023
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What cs249r_book does

This repository hosts the comprehensive textbook, assignments, and underlying systems code for Harvard University's course on engineering artificially intelligent systems. It addresses the critical intersection of machine learning algorithms and the computer systems required to execute them efficiently. The technical curriculum dives deep into hardware-aware model optimization, embedded machine learning (TinyML), distributed training, and the orchestration of cloud-scale ML pipelines. What sets this apart is its rigorous, academic approach to the full ML lifecycle, treating AI not just as mathematics, but as complex engineering systems that must be optimized for power, latency, and throughput. It provides world-class educational material completely open to the public.

This material is intended for advanced computer science students, systems engineers, and ML practitioners looking to understand the intersection of hardware and AI. It requires strong programming skills (C++/Python) and a foundation in computer architecture.

  • Full-Stack ML Curriculum: covers the entire spectrum of ML systems, from training models on distributed clusters to deploying them on microcontrollers.
  • TinyTorch Implementation: includes a custom, educational deep learning framework designed specifically to teach the internals of ML runtimes.
  • Hardware-Aware Optimization: provides deep dives into quantization, pruning, and compiling models for specific hardware architectures.
  • Continuous Validation: utilizes GitHub Actions to automatically test the course code and validate the Markdown builds of the textbook.
  • Multi-Language Support: offers translations of the core materials into multiple languages, expanding accessibility for global learners.

Where teams use it

Systems Engineering Education

Computer science students use the material to understand how popular frameworks like PyTorch and TensorFlow actually work under the hood.

Edge AI Development

Embedded engineers study the TinyML sections to learn techniques for deploying neural networks onto severely resource-constrained microcontrollers.

Infrastructure Scaling

MLOps professionals reference the cloud sections to design more efficient, distributed training pipelines that maximize GPU utilization.

Curriculum Development

Educators at other institutions fork the repository to adapt the high-quality assignments and textbook for their own advanced systems courses.

Getting started: Read the textbook directly on GitHub or follow the setup instructions in the README to build the TinyTorch environment.

README

dev branch

Machine Learning Systems

Principles and Practices of Engineering Artificially Intelligent Systems

English中文日本語한국어

Book TinyTorch Labs Kits MLSys·im
Slides Instructors StaffML Newsletter Updated

License Cite Fund Us

📘 Textbook📗 Vol I + 📘 Vol II🔥 TinyTorch🔬 Labs🔮 MLSys·im💼 StaffML

📚 Hardcopy edition coming 2026 with MIT Press.


Mission

The world is rushing to build AI systems. It is not engineering them.

That gap is what we mean by AI engineering.

AI engineering is the discipline of building efficient, reliable, safe, and robust intelligent systems that operate in the real world, not just models in isolation. Our mission is to establish AI engineering as a foundational discipline alongside software engineering and computer engineering, by teaching how to design, build, and evaluate end-to-end intelligent systems.

Our goal: Help 100,000 learners master ML Systems this year, and reach 1 million by 2030.


Why One Repository

I designed this as a single integrated curriculum, not a collection of independent projects. The textbook teaches the theory. TinyTorch makes you build the internals. The hardware kits force you to confront real constraints. The simulator lets you reason about infrastructure you can't afford to rent. Each piece exists because I found that students who only read don't internalize, and students who only code don't generalize.

The repository is the curriculum.

A growing community of contributors helps improve every part of it: fixing errors, sharpening explanations, testing on new hardware. Their work makes this better for everyone, and I'm grateful for every pull request.


The Curriculum

Every component connects. The textbook gives you the mental models. The labs let you reason through trade-offs interactively, powered by MLSys·im — a modeling engine for infrastructure you can't physically access, and a standalone tool in its own right. TinyTorch makes you build the machinery yourself. The hardware kits put you face-to-face with real deployment constraints. StaffML tests whether you actually understand it. Socratiq adds AI-guided reading, contextual quizzes, and spaced repetition inside the learning experience. And the instructor hub, slides, and newsletter give educators everything they need to bring this into a classroom.

Curriculum map showing how the textbook, labs, TinyTorch, hardware kits, MLSys·im, and StaffML connect

For Students

Component Role in the Curriculum Link
📖 Textbook Two-volume MIT Press textbook. The theory, the mental models, and the quantitative reasoning that everything else builds on. Vol I · Vol II
🔬 Labs Interactive Marimo notebooks where you explore trade-offs from the textbook: change a parameter, see what breaks, build intuition. Powered by MLSys·im under the hood. Launch labs · Repo guide
🔥 Tiny🔥Torch Build your own ML framework from scratch across 20 progressive modules. You don't understand a system until you've built one. Get started
🛠️ Hardware Kits Deploy ML to Arduino, Seeed, Grove, and Raspberry Pi devices. Real memory limits, real power budgets, real latency. Browse labs
🔮 MLSys·im Calculate memory bottlenecks, network saturation, and scheduling limits at infrastructure scales you can't physically access. Use simulator · Repo guide
💼 StaffML Physics-grounded interview questions for ML systems roles. Vault, practice drills, mock interviews, and progress tracking. Practice · Repo guide

For Educators

Component What It Provides Link
🎓 Instructor Hub The AI Engineering Blueprint: two 16-week syllabi, pedagogy guide, assessment rubrics, and a TA handbook. View hub · Repo guide
🎬 Lecture Slides Beamer slide decks for every chapter, with four theme variants. Drop into your course and teach. Browse decks · Repo guide
📬 Newsletter Updates on the curriculum, new chapters, and what the community is building. Subscribe

Choose Your Path

The pieces are designed to work together, but you do not need to adopt everything at once.

If you are... Start here Then go deeper
A student or self-learner Read Volume I and try Lab 00 Build TinyTorch, use MLSys·im, and practice with StaffML
An instructor Open The AI Engineering Blueprint Use the course map, slides, rubrics, and TA guide
A contributor Pick the component you use most Improve chapters, labs, tests, examples, hardware notes, simulator models, or assessment content

The learning loop is: Read → Explore → Build → Model → Deploy → Practice → Teach.

Adjacent and Experimental Work

Some projects are intentionally earlier-stage than the main curriculum:

  • Socratiq explores AI-guided reading, contextual quizzes, and spaced repetition for static learning sites.
  • MLPerf EDU is an under-construction pedagogical benchmark suite aligned with MLCommons MLPerf.
  • ML Systems Design Grammar is an experimental framework for reasoning from stable primitives, constraints, and rewrite rules.

What You Will Learn

This textbook teaches you to think at the intersection of machine learning and systems engineering. Each chapter bridges algorithmic concepts with the infrastructure that makes them work in practice.

You know... You will learn...
How to train a model How training scales across GPU clusters
That quantization shrinks models How INT8 math maps to silicon
What a transformer is Why KV-cache dominates memory at inference
Models run on GPUs How schedulers balance latency vs throughput
Edge devices have limits How to co-design models and hardware

Book Structure

The textbook follows the Hennessy & Patterson pedagogical model across two volumes:

Volume Theme Scope
📗 Volume I Build, Optimize, Deploy Single-machine ML systems (1–8 GPUs). Foundations, optimization, and deployment on one node.
📘 Volume II Scale, Distribute, Govern Distributed systems at production scale. Multi-machine infrastructure, fault tolerance, and governance.

FAQ

Who is this for, and what should I know first?

This is for anyone who wants to engineer intelligent systems, not only train models: students, working engineers moving into ML infrastructure, and educators building a course. We assume you can program in Python and have met basic machine learning ideas, but the book builds the systems concepts from the ground up. You do not need a background in computer architecture, distributed systems, or datacenter operations. Volume I starts at the foundations, and the rest of the curriculum (TinyTorch, labs, hardware kits, and the simulator) lets you learn by building rather than only by reading.

Do I need Volume I before Volume II? What is the difference?

The two volumes differ in scope, not depth. Both are equally rigorous. Volume I is the single-machine world: how an ML system works on one node with a handful of accelerators, from data and a single neuron's computation up through training, optimization, and deployment. Volume II is the at-scale world: many machines across a network, distributed training, fault tolerance, fleet orchestration, inference at scale, and governance. Volume II does not assume you have read Volume I, so you can start there if you already have the foundations. The natural path, though, is Volume I to build the mental models and Volume II to apply them across the fleet. The analogy we follow is Hennessy and Patterson: Computer Organization and Design first, then Computer Architecture: A Quantitative Approach.

Do I need to use TinyTorch, the labs, and the kits, or can I just read the book?

You can just read the book. Each volume stands on its own. The rest of the curriculum (TinyTorch, the labs, the hardware kits, the simulator, and the interview practice) exists to deepen what the book teaches by making you build and measure it, but none of it is required to follow the text. Start with the book, and reach for the hands-on pieces when you want a concept to become muscle memory.

Isn't this just a deep learning book?

Deep learning books (Goodfellow et al.'s Deep Learning, Bishop, d2l.ai, fast.ai) teach you to design and train models: architectures, optimization, and the mathematics of learning. They mostly stop at the model. This book starts where they leave off. It treats the model as one component inside a system that has to ingest data, run on real silicon under power and latency budgets, serve predictions reliably, and keep working as the world drifts. You can finish a deep learning course knowing how a transformer learns and still not know why it stalls on a 4,000-accelerator training run, what the KV cache does to your serving memory, or why your accelerator sits idle. That gap is what we teach. Learn the model from a deep learning text, then learn the system here.

Isn't this MLOps, or the same as Designing Machine Learning Systems?

This is the most common mix-up, because "ML systems" and "MLOps" sound interchangeable and several good practitioner books share the words. MLOps books are operations guides: how to wire up a feature store, a pipeline, and a deployment with today's tools. They are valuable, and they age with the tooling. This book teaches the layer underneath: the physics and quantitative reasoning that explain why those tools exist and what they cost. We ask which questions matter, why a design is the way it is, and what it cannot escape (bandwidth, latency, power, failure rates).

Think of the difference between following a recipe and understanding how cooking works. A recipe gives you exact steps for one dish: this temperature, this pan, this many minutes. It works beautifully until the oven, the ingredients, or the kitchen changes. Understanding why heat, salt, acid, and time transform food is different. It lets you cook in any kitchen, rescue a dish that is going wrong, and invent one that no recipe covers.

An MLOps book hands you the recipe for the stack you have today. This book teaches the underlying science, so you can reason about any stack, debug the one that is failing, and design the one that does not exist yet.

How is this different from a classic systems reference like The Datacenter as a Warehouse-Scale Computer?

References like Barroso, Hölzle, and Clidaras's The Datacenter as a Warehouse-Scale Computer are excellent. They distill how one organization engineered one canonical system, written by the people who built it. This project is a different kind of artifact, and the two are complementary rather than competing.

  1. Curriculum, not reference. A synthesis lecture documents a finished design for practitioners who already know the field. This book teaches the discipline from the ground up, with learning objectives, worked quantitative examples, labs, and an AI tutor, and it carries the reader from a single neuron (Volume I) all the way to the warehouse-scale fleet (Volume II).

  2. Vendor neutral, not a single stack. A vendor reference can say "here is how we do it" and quote real production numbers. We generalize across accelerators (GPU and TPU), across cloud and edge, and teach why a design is the way it is, so the reasoning survives the next hardware generation and transfers anywhere.

  3. Living, not a snapshot. A printed edition is frozen until its next revision. This is open source, continuously updated, and surrounded by code you build yourself (TinyTorch), hardware kits, a simulator, and interview practice.

In short, a warehouse-scale reference tells you how one machine was built. This curriculum teaches you to reason about why, and builds the judgment to design the next one.

Why read a textbook in the age of LLMs?

Because a textbook gives you something an LLM does not: perspective. An LLM is excellent at retrieval, and we are not trying to compete on retrieval. If a paragraph only delivers a fact you could get faster by asking a model, it has not earned its place. What a book builds instead is a structured mental model in the right order, the judgment to know which questions matter, and the reasoning behind why a design is the way it is and what it costs. Much of that comes from what a textbook chooses to leave out, since deciding what is central and what is peripheral is itself a lesson that an encyclopedic pile of facts cannot teach.

Bruce Davie makes this case well in "Textbooks in Tokenland" (Systems Approach): an LLM generates text that is not grounded in communicative intent, while a textbook is written by people trying to convey a model of the world to a reader. We agree, and we go one step further by building an AI tutor (SocratiQ) into the reading experience. The goal is not textbook versus LLM. A good book gives you the perspective to ask meaningful questions, and the LLM helps you answer them. Use each for what it does best.

Is it free, and how do I read it?

Yes. Both volumes are free to read online at mlsysbook.ai, and the textbook is open source under a Creative Commons license (CC BY-NC-SA 4.0), so you can share and adapt it for non-commercial use with attribution. If you prefer print, a hardcopy edition is coming in 2026 with MIT Press. The surrounding tools are open source too, each under its own license.


Quick Start

Read the textbook. Start with Volume I or continue to Volume II. It's the foundation for everything else.

Pick a hands-on path. Build a framework (TinyTorch), explore trade-offs (Labs), model constraints (MLSys·im), or deploy to real hardware (Kits).

Test yourself. Drill StaffML: physics-grounded systems design questions across cloud, edge, mobile, and TinyML.

Teach it. Adopt the curriculum with the AI Engineering Blueprint and lecture slides.

Branch Guide

Note

You are on the dev branch. Active development happens here. For the last stable release, see the main branch.

Branch What's on it Status
🟢 main
mlsysbook.ai
Single-volume textbook (current edition) Live — this is what readers see today.
🟡 dev
← you are here
Volume I — two-volume split (content complete, editorial polish)
Volume II — At Scale (active development)
Curriculum — TinyTorch, Kits, MLSys·im, Labs, StaffML
TinyTorch and Hardware Kits are live.
MLSys·im, Labs, and StaffML are early-release and actively iterated.

The two-volume split replaces the single-volume edition at launch.


Support This Work

Stars    Open Collective

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Star History Chart
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All contributions go to Open Collective, a transparent fund for educational outreach. Every dollar goes to reaching more students.

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Contributing

I want to... Go here
📖 Fix a typo or improve a chapter Textbook contributing guide
🔥 Add a TinyTorch module or fix a bug TinyTorch contributing guide
🛠️ Improve hardware labs Hardware kits guide
🔬 Improve interactive labs or simulator models Labs guide · MLSys·im guide
💼 Improve assessment or career-readiness content StaffML guide · quiz refresh guide
🧠 Improve AI learning tools Socratiq guide
🐛 Report an issue GitHub Issues
💬 Ask a question GitHub Discussions

License

This is a multi-component repository, and each component is released under its own license to match its purpose. The file inside each directory (e.g. tinytorch/LICENSE, interviews/staffml/LICENSE) is authoritative.

Component License What it means
Textbook (book/), Labs (labs/), Kits (kits/), Slides (slides/), Instructors (instructors/) CC-BY-NC-SA 4.0 Share and adapt for non-commercial use, with attribution and same-license sharing.
TinyTorch MIT Permissive — use, modify, redistribute, including commercially.
MLSys·im Apache 2.0 Permissive with explicit patent grant.
StaffML AGPL v3 Strong copyleft — modifications to deployed services must be published. Commercial licensing available; contact the authors.
StaffML question corpus CC BY-NC 4.0 Research and educational use; commercial use requires permission.
TinyDigits dataset BSD 3-Clause Permissive (matches sklearn ancestry).
TinyTalks dataset CC BY 4.0 Permissive with attribution; commercial use allowed.

A user-facing summary lives at mlsysbook.ai/about/license.

If you are an institution considering adoption, or a company interested in commercial terms for a copyleft component, please reach out to edu@tinyML.org.


Contributors

Thanks goes to these wonderful people who have contributed to making this resource better for everyone!

Legend: 🪲 Bug Hunter · 🧑‍💻 Code Contributor · ✍️ Doc Wizard · 🎨 Design Artist · 🧠 Idea Spark · 🔎 Code Reviewer · 🧪 Test Tinkerer · 🛠️ Tool Builder

📖 Textbook Contributors

Vijay Janapa Reddi
Vijay Janapa Reddi

🪲 🧑‍💻 🎨 ✍️ 🧠 🔎 🧪 🛠️
Zeljko Hrcek
Zeljko Hrcek

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  1. Machine Learning Systems: Volume I v0.7.0 and Volume II v0.2.0vol1-v0.7.0+vol2-v0.2.0Jun 24, 2026264 downloads

    ## Machine Learning Systems: Volume I v0.7.0 and Volume II v0.2.0 This release ships a comprehensive editorial and production pass across both volumes, refreshing the HTML, PDF, and EPUB builds. It also answers the question we hear most often, so this note opens with a clear guide to what each volume covers and which one to read. --- ## 📚 Which volume should I read? Volume I vs Volume II **Short answer:** Volume I teaches you how a machine learning system works and how to build one. Volume II teaches you what changes when machine learning runs at scale, across many machines, many users, and long-lived production fleets. Volume I is about the single system. Volume II is about the fleet. The two volumes are separate, self-contained reading paths. Volume I assumes no prior systems background and is the place to start. Volume II assumes you are comfortable with the foundations from Volume I and goes deep on large-scale and production concerns. | | **Volume I** | **Volume II** | |---|---|---| | **Title** | *Introduction to Machine Learning Systems* | *Machine Learning Systems at Scale* | | **Version** | v0.7.0 | v0.2.0 | | **Core question** | How do you build, train, optimize, an

  2. ## TinyTorch v0.1.13 Patch release focused on **framework correctness**. It lands autograd, convolution, attention, and quantization fixes that close real gradient and numerical stability bugs, plus a substantial hardening of the **release and grading pipeline** (nbgrader tiers, `tito` preflight, PDF builds) and a round of **community dashboard** repairs. Version bumped from `0.1.12` to `0.1.13`. ### ✨ New Features - **AvgPool2d autograd backward** (M09 `convolutions`): `AvgPool2d` now participates in the autograd graph, distributing the upstream gradient uniformly across each pooling window so convolutional milestones can be trained from input to loss. (PR by @vedant-a-joshi) ### 🐛 Framework Correctness (autograd and ops) The core of this release. Each fix addresses a case where the framework silently produced wrong gradients or values: - **MatmulBackward for 1D vector inputs** (M06 `autograd`): corrected gradient computation when one or both operands are 1D. The vector and matrix broadcasting in the backward pass was previously mishandled. - **`tracked_mul` scalar handling** (M06 `autograd`, #1871): now wraps a raw scalar in a `Tensor` before passing it to `MulBackward` in

  3. Lecture Slides (Latest)slides-latestMay 11, 20264.8K downloads

    ## ML Systems Lecture Slides Complete slide decks for the ML Systems curriculum. **Volume I** (17 decks): Introduction through Conclusion — single-machine ML systems **Volume II** (18 decks): Introduction through Conclusion — distributed ML at scale **TinyML** (5 chapters): HarvardX Professional Certificate — edge & embedded ML Vol I/II decks include speaker notes, active learning exercises, and original SVG diagrams. ### Downloads — PDF - **MLSysBook-Slides-All-PDF.zip** — All 35 Vol I/II decks - **MLSysBook-Slides-Vol1-PDF.zip** — Volume I only - **MLSysBook-Slides-Vol2-PDF.zip** — Volume II only ### Downloads — PowerPoint Image-based PPTX (not editable text) — use for presenter mode and annotations. - **MLSysBook-Slides-All-PPTX.zip** — All 35 Vol I/II decks - **MLSysBook-Slides-Vol1-PPTX.zip** — Volume I only - **MLSysBook-Slides-Vol2-PPTX.zip** — Volume II only ### Downloads — TinyML (HarvardX edX) - **MLSysBook-TinyML-All.zip** — All slides, readings, and supplementary materials - **MLSysBook-TinyML-Slides.zip** — 178 slide decks only - **MLSysBook-TinyML-Readings.zip** — 127 readings only Individual Vol I/II chapter files (PDF + PPTX) are also attached below. ### Sou

  4. ## TinyTorch v0.1.10 Largest Lab Guide upgrade since the series began, plus substantive framework work: new Tensor API surface (`view`, `masked_fill`, `ndim`, `numel`, `contiguous`), `no_grad()` context manager, Python 3.10+ baseline, 28 security alerts resolved, seven batches of module-audit fixes, reproducibility via seeded `default_rng(7)`, and 847/847 tests green. ### ✨ New Features **Lab Guide PDF** (the flagship of this release) - **Glossary back matter**: 90 alphabetical entries covering tensor/memory, autograd, training systems, architecture, optimization, and ML basics, with module cross-references (see `glossary.qmd`). - **Module opener hooks**: every module starts with a 2–3 sentence systems-first framing paragraph leading with memory, bandwidth, arithmetic intensity, HBM, or roofline implications before the ML story. - **Code listing captions + List of Listings**: ~60 substantive code blocks carry `Listing N.M — Description` captions; populates a new List of Listings in the front matter. - **List of Figures + List of Tables** in front matter (151 newly-captioned tables). - **Running headers with chapter + section**: verso `Chapter N · Title`, recto `N.M · Section`,

  5. MLSys·im 0.1.1mlsysim-v0.1.1Apr 24, 2026197 downloads

    # MLSys·im 0.1.1 — Paper Title Correction *First-principles infrastructure modeling for the [Machine Learning Systems](https://mlsysbook.ai) textbook.* Metadata-only patch release. No code or API changes; safe drop-in replacement for 0.1.0. Corrects the paper title cited in three places to match the actual title of the companion paper. ### 📚 Documentation - **Paper title corrected** across `CITATION.cff`, the BibTeX snippet in `README.md`, and the reference docstring in `mlsysim/core/walls.py`. Was: *"A Composable Analytical Framework for Machine Learning Systems."* Now: *"MLSys·im: First-Principles Infrastructure Modeling for Machine Learning Systems."* ### 🏗️ Packaging & Dependencies - Version bumped to `0.1.1` across `pyproject.toml`, `mlsysim/__init__.py`, and `CITATION.cff`; `date-released` updated to `2026-04-24`. ### Contributors - @profvjreddi --- ## Install pip install --upgrade mlsysim==0.1.1 --- ## Links - [PyPI · mlsysim 0.1.1](https://pypi.org/project/mlsysim/0.1.1/) - [Documentation](https://mlsysbook.ai/mlsysim/) - [Full CHANGELOG](https://github.com/harvard-edge/cs249r_book/blob/dev/mlsysim/CHANGELOG.md) - [Diff mlsysim-v0.1.0 → mlsysim

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