PySAD
github.com
What it is
PySAD is a free, open-source Python framework for online anomaly detection in streaming data. Its models update when each new data instance arrives, supporting sequential detection for univariate and multivariate data. The project describes 16 online detectors, including xStream, LODA, RS-Hash, Half-Space Trees, and Robust Random Cut Forest. It also provides stream simulators, evaluators, preprocessors, statistic trackers, postprocessors, and probability calibrators. Integrations allow batch anomaly detectors from PyOD to run in a streaming setting. Experiments can use supervised, semi-supervised, or unsupervised settings. The documentation says streaming methods may retain one instance or a small recent window to meet memory and processing constraints. Installation is available through pip or the GitHub source; the current README lists Python 3.10 or newer on Linux, macOS, and Windows. PySAD is self-hosted and distributed under a BSD 3-Clause license. Its plan costs nothing, and 17 labelled benchmark datasets are downloaded on first use.
Spec sheet
- Purpose
- PySAD is an open-source Python framework for anomaly detection on streaming multivariate data.Read 2 Oct 2026 · pysad.readthedocs.io
- Security
- The repository links to a security policy, but the policy page could not be opened during this research.Read 2 Oct 2026 · github.com
- Support
- The maintainer says issues and pull requests are welcome and aims to reply within a few days; questions and show-and-tell go in GitHub Discussions.Read 2 Oct 2026 · github.com
- License
- The project is distributed under a BSD 3-Clause license.Read 2 Oct 2026 · github.com
- Benchmarks
- The README says 17 labelled benchmark datasets are downloaded on first use.Read 2 Oct 2026 · github.com
- Data and learning settings
- The framework supports models for univariate and multivariate data and experiments in supervised, semi-supervised, and unsupervised settings.Read 2 Oct 2026 · pysad.readthedocs.io
- Detectors
- The repository describes 16 online detectors, including xStream, LODA, RS-Hash, Half-Space Trees, and Robust Random Cut Forest.Read 2 Oct 2026 · github.com
- Evaluation tools
- PySAD includes stream simulators, evaluators, preprocessors, statistic trackers, postprocessors, and probability calibrators.Read 2 Oct 2026 · pysad.readthedocs.io
- Installation
- The project can be installed with pip or from its GitHub source, and its current README lists Python 3.10 or newer on Linux, macOS, and Windows.Read 2 Oct 2026 · github.com
- Maintainer
- The GitHub profile identifies Selim Firat Yilmaz as an AI researcher based in London, UK.Read 2 Oct 2026 · github.com
- Online detection
- Its models update as each new data instance arrives for online or sequential anomaly detection.Read 2 Oct 2026 · pysad.readthedocs.io
- PyOD integration
- PySAD provides integrations that let batch anomaly detectors from PyOD run in a streaming setting.Read 2 Oct 2026 · pysad.readthedocs.io
- Resource use
- The documentation says streaming methods may store only an instance or a small window of recent instances to meet memory and processing constraints.Read 2 Oct 2026 · pysad.readthedocs.io
Plans and prices
Strong points and limits
Strong points
- Models update as each data instance arrives.
- Includes 16 online detectors.
- Integrates batch detectors from PyOD for streaming use.
- Supports Linux, macOS, and Windows.
Limits
- Requires Python 3.10 or newer.
- 17 labelled benchmark datasets download on first use.
- Deployment is self-hosted.
Who it suits
PySAD suits Python users working on streaming anomaly detection, including those evaluating univariate or multivariate data in supervised, semi-supervised, or unsupervised settings.
Verdict
PySAD provides a broad set of streaming detection and evaluation components at no cost. Its Python version requirement and self-hosted deployment are important setup considerations.
Where Specifiction places it
- Anomaly Detection Software#14 of 227.4