Fishery vs Snowfakery
Fishery
github.comSnowfakery
snowfakery.readthedocs.ioSide by side
| Figure | Fishery | Snowfakery |
|---|---|---|
| Price from | Free | Free |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | — |
| Linux | — | Yes |
| API | — | Yes |
| Self-hosted | — | Yes |
| Plans published | 1 | 1 |
| Spec score · Test Data Generation Tools | 7.7 (#11) | 7.9 (#8) |
| Installation | The README gives npm and Yarn commands for installing Fishery as a development dependency. | The documentation instructs non-Salesforce users to install Snowfakery with pipx and recommends installing CumulusCI for Salesforce use. |
| Purpose | Fishery is a JavaScript library for setting up objects for tests and other data needs. | Snowfakery generates unique, random fake data with relationships between tables from YAML recipe files. |
| Security | The repository lists a security policy resource, but the opened page did not provide policy details. | The documentation warns that recipes can access much of Python's power, load plugins, and call Python methods, so it advises against running untrusted recipes where they can access secure resources. |
Plans
In their own words
Fishery
Fishery is a free JavaScript library for preparing objects as test data and for other situations where JavaScript data needs setup. Its factories define defaults, and build() creates objects with supplied parameters layered over those defaults. TypeScript users can obtain typed factory parameters and return objects, while the library also works without TypeScript. Factories may define onCreate behavior for asynchronous work; create() then performs that work and returns a promise. Additional factory capabilities include sequences, transient parameters, associations, and hooks that run after building or creating objects. Developers can extend factories with reusable builder methods by subclassing Factory. The documentation describes using factories alongside other factories to build associated objects. Installation instructions cover npm and Yarn as development dependencies. The repository identifies Fishery as free software under the MIT license and says thoughtbot, inc. maintains and funds it. GitHub Issues is the listed channel for bug reports and change requests.
Snowfakery
Snowfakery generates synthetic data from YAML recipe files, including records linked across tables. Recipes can create names, addresses, text, URLs, random numbers and other values using Faker-based functions, and specify how many related objects to generate. Output can go to files in JSON, TXT, CSV, SQL, DOT, SVG, SVGZ, JPEG and PostScript formats; some diagram formats require Graphviz. Snowfakery can also write to databases accessible through SQLAlchemy, including SQLite, and generate records in Salesforce when used through CumulusCI. Python applications can embed it with its generate_data function, and Python plugins and providers can extend its functions and Faker capabilities. Strict mode checks a recipe before generation, while validate-only mode checks it without generating data. It is free, open source and self-hosted. The documentation says database output creates new tables, with generated columns as text, and that SQLite is the only database included in its SQL dataset URL test suite. The repository was archived on September 18, 2026, and is read-only.