ActiveCampaign vs Windmill

ActiveCampaign is an email marketing and marketing automation platform headquartered in Chicago. Jason VandeBoom founded it in 2003 as on-premises software before it moved to SaaS. Its core job is to send the right email, SMS or WhatsApp message at the right time based on what a contact does, using a visual automation builder with branching logic.

The automation builder handles multi-step journeys with waits, conditions, goals and split tests, triggered by site visits, purchases, form fills, tags or CRM events. Campaigns use 250+ templates and, on Pro, predictive sending, conditional content and attribution. Since 2025 the Active Intelligence layer adds AI agents that build segments, automations and brand kits, a conversational workspace, and a remote MCP server; every plan includes 500 AI credits a month. Plans are priced by contacts: Starter ($19/month for 1,000 contacts billed monthly) covers email and automation, Plus adds landing pages, generative AI and SMS, Pro adds advanced segmentation and three seats, and Enterprise adds SSO, HIPAA support and custom objects. CRM pipelines, WhatsApp and transactional email are add-ons.

ActiveCampaign suits SMBs, ecommerce stores and agencies that need deep automation without HubSpot pricing. Mailchimp is easier for simple newsletters, Brevo and MailerLite are cheaper at large lists, and HubSpot is stronger as an all-in-one CRM.

Buying tip: prices rise steeply with contact count, so clean inactive contacts before upgrading. The 14-day trial needs no card, and annual billing saves roughly 17 to 21%.

Windmill is an open-source developer platform for scripts, workflows and internal tools, built by Windmill Labs, a startup founded by Ruben Fiszel. Its premise is that most internal automation starts as a script: you write code in Python, TypeScript, Go, Bash, SQL, PHP or other languages, and Windmill turns it into a shareable job with an auto-generated UI, permissions, logs and an API endpoint.

Scripts can be chained into flows with branches, loops, retries, approvals and error handlers, triggered by schedules, webhooks, HTTP routes, emails or message queues. An app builder creates dashboards and admin panels on top of those scripts, and a web IDE with dependency management and AI assistance speeds up development, while a CLI and git sync let teams manage everything as code. The execution engine is designed for low overhead and high throughput, which makes Windmill viable for data pipelines and background jobs. The Community edition is free to self-host; the cloud Team plan is priced per user plus compute, and Enterprise adds SSO, audit logs, SLAs and scaling features.

Windmill suits engineering and data teams that want one platform to replace a mix of cron jobs, Airflow DAGs and Retool apps. It is code-first, so non-technical users will prefer Zapier, Make or n8n, and its community is smaller than older tools. Airflow and Prefect remain more common for large data orchestration, Retool is more mature for complex UIs, and Temporal is better for long-running, durable application workflows.