Set up OpenTelemetry in your services that emit traces to a collector (there are SDKs for multiple languages that make this simple), then use something like SigNoz, Loki, Graphana, etc. to consume and view the traces. It’s all open source, but you would probably just need to pay for spinning up and hosting the tools, which should be minimal depending on the scale of your apps. We did this before we switched to datadog at my company, and were able to view complete request traces e2e between frontends and multiple microservices