Prefect vs Windmill
Prefect
prefect.io
Windmill
windmill.devSide by side
| Figure | Prefect | Windmill |
|---|---|---|
| Price from | $100/mo | $120/mo |
| Free plan | Yes | Yes |
| Free trial | — | Yes |
| Open source | — | Yes |
| Web | Yes | Yes |
| Windows | — | Yes |
| Linux | — | Yes |
| API | Yes | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 4 | 4 |
| Spec score · Workload Automation Software | 8.0 (#12) | 8.6 (#7) |
| Spec score · Workflow Orchestration Software | 7.9 (#22) | 8.6 (#11) |
| Founded | 2018 | 2022 |
| Integrations | The integrations directory lists AWS, Azure, Bitbucket, Dask, Databricks, dbt, Docker, GCP, GitHub, Kubernetes, Slack, Snowflake, and other integrations. | Windmill Hub lists more than 200 resource types, including Google services, GitHub, GitLab, Slack, Microsoft Teams, AWS, S3, BigQuery, ClickHouse, Datadog and Discord. |
| Security | Prefect states that it is SOC 2 Type II certified and GDPR compliant, and describes itself as HIPAA ready. | Windmill lists granular permissions, RBAC, secret management, OAuth, SSO and audit logs among its enterprise features. |
| Security controls | The security page lists TLS 1.2 or higher, encryption at rest, workspace-unique encryption keys, RBAC, SSO, SCIM, audit logs, and IP allowlisting. | The platform documents PID namespaces, optional NSJAIL sandboxing, agent workers and worker groups for process isolation. |
| Support | The pricing comparison lists Community as Hobby's support channel, and the homepage says every enterprise plan has a 30-minute response SLA. | The free self-hosted plan includes community support on Discord, while Enterprise lists 24/7 priority support with a 3-hour response time. |
Plans
Windmill
- Free and Open-sourceFree
- Free and Open-sourceFree
- Enterprise$120 a month
- Enterprise example configuration$170 a month
In their own words
Prefect
Prefect is a workflow orchestration platform for data, machine learning and agent workflows written in Python. Its open-source framework lets users add decorators to existing Python code to create workflows, without a rigid DAG structure or custom DSL. Execution features include state tracking, automatic retries, caching and recovery from failures. For observability, Prefect provides run timelines, logs and alerts for failures, missed SLAs and late runs. Workflows can run on cron or event-driven schedules, support backfills, and be triggered by webhooks, cloud events or state changes. Deployment choices include managed serverless execution, hybrid execution in a customer’s infrastructure, and self-hosted orchestration. In hybrid mode, workers connect through outbound-only connections while code and data stay in the customer’s infrastructure; Prefect Cloud hosts the control plane and metadata. The free Hobby plan is limited to two users, five deployments, 500 minutes of monthly serverless credits and seven days of run retention. Paid plans start at $100/mo.
Windmill
Windmill is an open-source workflow engine and developer platform for building endpoints, workflows and user interfaces. It is aimed at teams making internal software across engineering, data, sales, support and marketing. Scripts can be written in TypeScript, Python, Go, PHP, Bash, C#, SQL, Rust, Ruby and R, among other languages. Windmill combines a script editor, low-code flow builder, and low-code, React or Svelte app builders. Scripts and flows can be triggered by webhooks, schedules, HTTP routes, queues or an open API. Its Hub lists more than 200 resource types, including GitHub, Slack, AWS, BigQuery and PostgreSQL; users can also define custom resource types with schemas. Local development through the CLI and Git sync support version control and deployment workflows. Self-hosting is supported. The free and open-source plan is free and includes three workspaces, 50 users, 10 GiB of workspace object storage and 100 guest app users per 30 days. Enterprise is $120 a month and includes a month-long trial. Enterprise features include granular permissions, RBAC, secret management, OAuth, SSO and audit logs.