Source: https://seerepo.com/compare/dagster-io/dagster/vs/ray-project/ray
Markdown source: https://seerepo.com/compare/dagster-io/dagster/vs/ray-project/ray.md
Description: dagster and ray share 31 technologies: React, azure-storage-blob, Celery, pyarrow, deltalake, Google Cloud Storage, Google, FastAPI, graphene, starlette, AIOHTTP, uvicorn, react-router-dom, Rich, SQLAlchemy, alembic, sqlglot, azure-identity, pyjwt, oauth2client, MLflow, markdown, jinja2, Pydantic, jsonschema, validators, boto3, kubernetes, docker, psutil, and prometheus-client. Both are written in Python.

# dagster vs ray

dagster and ray share 31 technologies: React, azure-storage-blob, Celery, pyarrow, deltalake, Google Cloud Storage, Google, FastAPI, graphene, starlette, AIOHTTP, uvicorn, react-router-dom, Rich, SQLAlchemy, alembic, sqlglot, azure-identity, pyjwt, oauth2client, MLflow, markdown, jinja2, Pydantic, jsonschema, validators, boto3, kubernetes, docker, psutil, and prometheus-client. Both are written in Python.

- [dagster-io/dagster](https://seerepo.com/r/dagster-io/dagster): An orchestration platform for the development, production, and observation of data assets.
- [ray-project/ray](https://seerepo.com/r/ray-project/ray): Ray is an AI compute engine. Ray consists of a core distributed runtime and a set of AI Libraries for accelerating ML workloads.

## What they share and what sets them apart

- In common: React, azure-storage-blob, Celery, pyarrow, deltalake, Google Cloud Storage, Google, FastAPI, graphene, starlette, AIOHTTP, uvicorn, react-router-dom, Rich, SQLAlchemy, alembic, sqlglot, azure-identity, pyjwt, oauth2client, MLflow, markdown, jinja2, Pydantic, jsonschema, validators, boto3, kubernetes, docker, psutil, prometheus-client
- Only in dagster: azure-storage-file-datalake, db-dtypes, dbt-core, mysql-connector-python, psycopg2-binary, snowflake-sqlalchemy, dlt, DuckDB, clickhouse-driver, MySQL, pyspark, Next.js, React Router, lru-cache, bokeh, questionary, flask-session, google-auth, deepeval, OpenAI, wordcloud, cattrs, Prefect, structlog, azure-core, coloredlogs, Datadog, validator, highlight.js, react-markdown, remark, remark-gfm, codemirror, Radix UI, TanStack, @blueprintjs/core, @react-hook/resize-observer, react-day-picker, sonner, yaml, chartjs-adapter-date-fns, Chart.js, dagre, react-chartjs-2, visx, @rjsf/core, ansi-to-react, chartjs-plugin-zoom, rehype-highlight, rehype-sanitize, remark-breaks, rjsf
- Only in ray: amqp, async-lru, azure-common, azure-datalake-store, confluent-kafka, diskcache, expiringdict, gitdb, google-cloud-core, h5py, kombu, pickleshare, pylance, pymongo, aioboto3, MongoDB, Redis, adlfs, smart-open, pyiceberg, pymysql, clickhouse-connect, gcsfs, fastavro, pyzmq, s3fs, webdataset, Hugging Face, Kafka, asgiref, Flask, flask-cors, graphql-core, graphql-relay, jupyter-core, jupyterlab-server, werkzeug, Ray, Lightning, anyio, tornado, alabaster, cycler, fonttools, jupyterlab-pygments, pydata-sphinx-theme, soupsieve, sphinx-design, tinycss2, contourpy, glfw, jupyter-server-terminals, jupyterlab-widgets, matplotlib-inline, Plotly, prompt-toolkit, pyopengl, Textual, widgetsnbextension, xyzservices, Gradio, ipywidgets, matplotlib, pydot, peewee, argon2-cffi, argon2-cffi-bindings, flask-basicauth, google-auth-oauthlib, itsdangerous, joserfc, jwcrypto, keyring, msal, msal-extensions, oauthlib, requests-oauthlib, cryptography, google-auth-httplib2, albucore, bitsandbytes, cmdstanpy, crcmod, cupy-cuda12x, cupy-cuda13x, einops, fairscale, gradio-client, gym, LangChain, llvmlite, lm-eval, ml-dtypes, nltk, ONNX, onnxruntime, onnxscript, openai-whisper, opt-einsum, orbax-checkpoint, peft, prophet, rouge-score, sacrebleu, safetensors, scikit-image, sentencepiece, skops, tf-keras, tiktoken, timm, tokenizers, torchtext, triton, gymnasium, torch, transformers, TensorFlow, jax, torchvision, xgboost, lightgbm, scikit-learn, accelerate, datasets, pytorch-lightning, evaluate, flax, Keras, torchmetrics, albumentations, deepspeed, diffusers, hyperopt, Optuna, pettingzoo, tensordict, tensorflow-datasets, tensorflow-probability, torchaudio, bleach, defusedxml, et-xmlfile, imageio, imageio-ffmpeg, imagesize, jsonlines, linkify-it-py, lxml, mako, markdown-it-py, markupsafe, mdurl, mistune, moviepy, nbconvert, nh3, openpyxl, pandocfilters, ruamel-yaml, webencodings, xlrd, xmltodict, pillow, docutils, beautifulsoup4, av, nbformat, torchcodec, annotated-types, fastjsonschema, fqdn, jsonschema-specifications, pathvalidate, pydantic-core, referencing, rfc3339-validator, rfc3986, rfc3986-validator, openapi-schema-validator, aiobotocore, azure-mgmt-compute, azure-mgmt-resource, colorlog, Gunicorn, opentelemetry-api, opentelemetry-instrumentation, opentelemetry-semantic-conventions, python-json-logger, botocore, OpenTelemetry, opentelemetry-exporter-prometheus, opentelemetry-exporter-otlp-proto-grpc, opentelemetry-instrumentation-fastapi, typeface-roboto, MUI, usehooks-ts, lowlight, react-window, react-icons, @mui/icons-material, js-yaml

## Side by side

| | dagster | ray |
|---|---|---|
| Size | 1,373,416 lines written, 3,347 code files | 1,531,664 lines written, 2,777 code files |
| Who writes it | 1.4% of its commits signed by AI. With Claude Code, Gemini CLI, and Aider | 3.6% of its commits signed by AI. With Claude Code, Gemini CLI, GitHub Copilot, Cursor, and Codex |
| Activity | Last push November 7, 2026, 28,090 commits, 16,376 stars | Last push November 6, 2026, 32,373 commits, 44,213 stars |
| Tests | 2,682 test files. 15.3% of its code files have a test that imports them | 2,168 test files. 9.7% of its code files have a test that imports them |

- Size: Lines written by people and agents, without generated ones; code files, without tests.
- Who writes it: A commit counts as AI's when it carries its signature: a Co-Authored-By line, its author name or the merge of its branch.
- Activity: From GitHub and its history, on the day SeeRepo read it.
- Tests: The files that test the code, and the share of code files a test imports.

## Frequently asked questions

### Which is bigger, dagster or ray?

ray, with 1,531,664 lines written; dagster has 1,373,416.

The proof: [ray-project/ray's code at commit 77567c5](https://github.com/ray-project/ray/tree/77567c5c5790e9e91aa40a5af93004ef958c2ffc)

### Which has more GitHub stars, dagster or ray?

ray, with 44,213 stars; dagster has 16,376.

The proof: [ray-project/ray on GitHub](https://github.com/ray-project/ray)

### Which has more tests, dagster or ray?

dagster, with 2,682 test files; ray has 2,168.

The proof: [dagster-io/dagster's code at commit 55208da](https://github.com/dagster-io/dagster/tree/55208da7a9dc8fe3cea511d39508b97f73ab8769)

### Which was updated more recently, dagster or ray?

dagster: its last push was on November 7, 2026, and ray's on November 6, 2026.

The proof: [dagster-io/dagster's commits on GitHub](https://github.com/dagster-io/dagster/commits)

### Which has more commits signed by AI, dagster or ray?

ray: an AI signed 3.6% of its commits, with Claude Code, Gemini CLI, GitHub Copilot, Cursor, and Codex; in dagster, 1.4%.

The proof: [the commits each tool signed in ray-project/ray](https://seerepo.com/r/ray-project/ray/ai)

## Sources

- dagster-io/dagster: Read on November 7, 2026, at commit 55208da (https://github.com/dagster-io/dagster/tree/55208da7a9dc8fe3cea511d39508b97f73ab8769)
- ray-project/ray: Read on November 6, 2026, at commit 77567c5 (https://github.com/ray-project/ray/tree/77567c5c5790e9e91aa40a5af93004ef958c2ffc)

## What is your repo built with?

Any public repo, with no account: https://seerepo.com/r/owner/repo/built, with the owner and name it has on GitHub.