Open-source software stack for AI automation agencies
For agencies that build AI agents and automations for clients and want to own the platform, keep client data under their control and stop reselling per-seat SaaS.
12 tools · saves about $4,884/yr for a team of 10 · picks reviewed Oct 2026
Workflow automation
Replaces Zapier · Team, 2,000 tasks (billed yearly) · $69/mo · checked Oct 2026
Source-available. Biggest automation community and integration library; Activepieces (MIT) if you host flows for clients.
Also good: Activepieces
AI agents & apps
Replaces Relevance AI · Team · not counted · Team plan priced by sales since May 2026 · checked Oct 2026
MIT lets you white-label client agents freely; Dify is as popular but needs a licence for multi-tenant or rebranded use.
Also good: Dify
Client-facing AI chat
Replaces ChatGPT Business · Standard seat (billed yearly) · $20/user/mo · 10 seats · checked Oct 2026
MIT and works with every model provider; Open WebUI is more popular but its licence restricts rebranding.
Also good: Open WebUI
Private & local models
Replaces OpenAI API · not counted · Pay per token · checked Oct 2026
Extra running cost: GPU server, $250/mo
Runs open models on your own hardware for clients who can't send data to a cloud API.
LLM tracing & evals
Replaces LangSmith · Plus · $39/user/mo · 5 seats · checked Oct 2026
The most-used open LLM observability tool: traces, costs and evals per client project.
Vector database
Replaces Pinecone · Standard (monthly minimum) · $50/mo · checked Oct 2026
Fast vector search for RAG agents that is simple to self-host per client.
CRM & pipeline
Replaces HubSpot · Sales Hub Starter (billed yearly) · $15/user/mo · 3 seats · checked Oct 2026
Modern, API-first CRM agencies can extend with custom objects and automations.
Also good: EspoCRM
Proposals & e-signatures
Replaces DocuSign · Standard (billed yearly) · $25/user/mo · 2 seats · checked Oct 2026
The most popular open e-signing tool, with templates and an audit trail you host.
Also good: OpenSign
Client projects
Replaces ClickUp · Business (billed yearly) · $12/user/mo · 10 seats · checked Oct 2026
Fast issues, cycles and client-friendly views; the most popular open project tool.
Also good: Leantime
Scheduling
Replaces Calendly · Standard (billed yearly) · $10/user/mo · 5 seats · checked Oct 2026
Purpose-built booking pages per person and service, with reminders and calendar sync.
Invoicing
Replaces QuickBooks · Online Simple Start · $38/mo · checked Oct 2026
Source-available. Retainers, recurring invoices and a client portal; Akaunting's licence caps it at two users.
Hosting client deployments
Replaces Render · Pro workspace (compute billed separately) · $25/mo · checked Oct 2026
Deploys n8n, Langflow and client apps to your own servers from one dashboard.
Also good: Dokploy
How we calculate
For each paid tool you tick, we take its public list price for the plan shown and multiply it by the seats your team would need. Some tools are only used by part of a team, so a row may count a share of your team or a fixed number of seats; the row says how many. Prices that depend on sales or usage are shown but not counted.
From that we subtract an estimate for running the open-source stack yourself: $165/month plus $2 per person per month (Two 8 vCPU / 16 GB cloud servers, plus storage per person), and any extra running cost a row lists, such as a GPU. The time it takes to set up and maintain the tools is not included.