Should you build your own product analytics?
Mixpanel pricing at scale gets painful. But event tracking is deceptively complex. Here's when to build, vibe, or buy.
The landscape has shifted
Product analytics used to be firmly "buy" territory. But three things changed:
1. Open source caught up. PostHog, Plausible, and Umami are legitimate alternatives with self-hosting options.
2. Warehouse-native analytics emerged. If your data is already in BigQuery/Snowflake, tools like Metabase or even SQL + dashboards might be enough.
3. Vibe coding makes dashboards trivial. Claude can build you a React dashboard with charts in an afternoon. The hard part was never the UI.
Build / vibe when...
- Data already lives in your warehouse
- You need custom metrics nobody else has
- Privacy/compliance requires self-hosting
- Simple pageviews + events (vibe it)
- You have data engineers on staff
Buy when...
- You need funnels, cohorts, retention
- Product team needs self-serve
- You want session replay
- A/B testing is important
- You don't have data engineering
The open source option
This category has a strong middle path: self-hosted open source. PostHog gives you Mixpanel-level features (funnels, retention, session replay) with a generous free tier and self-hosting option.
If you're considering building, try PostHog self-hosted first. You get 80% of a custom solution's control with 20% of the effort.
What about vibe coding?
Analytics has two parts: data collection and data visualization. Vibe coding is great for visualization — dashboards, charts, custom views. It's terrible for collection.
The event tracking SDKs, data pipelines, and storage systems are genuinely hard. Don't vibe that part. But once your data is in a database, building custom dashboards is a perfect vibe project.
Hybrid approach: Use a lightweight tracker (PostHog, Segment, or even Google Analytics) for collection. Vibe code custom dashboards that query your data warehouse for the specific views you need.
Real cost comparison
For a product with 100K monthly active users over 3 years:
| Build | PostHog (Self-host) | Mixpanel | |
|---|---|---|---|
| Initial cost | $150K – $300K | $10K – $30K | $0 |
| Annual cost | $80K – $120K | $20K – $50K (infra) | $24K – $60K |
| Time to launch | 4 – 9 months | 1 – 2 weeks | Days |
| 3-year total | $400K – $660K | $70K – $180K | $72K – $180K |
What people underestimate
Event schemas evolve. Tracking is easy on day one. Maintaining consistent events across a growing codebase, multiple platforms (web, iOS, Android), and changing product features? That's ongoing work.
Querying at scale is hard. When you have billions of events, simple queries like "show me all users who did X then Y within 7 days" require serious infrastructure.
Product teams aren't SQL-fluent. Your PMs want self-serve analytics. If everything requires an analyst to write a query, you've built a bottleneck.
Compare tools
Our take
PostHog self-hosted is the sweet spot for most.
Pure "build" rarely makes sense unless you have data engineers and very specific requirements. Between Mixpanel and building custom, PostHog offers the best of both: control, self-hosting, and modern features without the vendor pricing. If you're smaller or don't want to run infrastructure, Mixpanel's free tier is generous.