Standard local ports
Keep your OTEL exporter pointed at localhost:4317 and start
debugging instead of translating every example into a custom local stack.
Local observability without the local stack
OpenTelemetry traces and logs. One binary. Your laptop.
Lantern accepts OTLP on the standard local ports, stores traces and logs in SQLite, and gives you both a browser UI and terminal UI for inspection. No Jaeger plus Loki plus Grafana setup. No separate hosted dependency.
OTLP gRPC + HTTP
browser UI
terminal UI
SQLite storage
local-first
Why Lantern
Collapse the local observability stack into one command.
Jaeger gives you traces. Loki gives you logs. Grafana expects everything around it. Lantern is for the moment when that stack is too heavy for a laptop debugging loop and you just want your OpenTelemetry exporter pointed at localhost.
Logs and traces together
Lantern is useful because it keeps trace waterfalls, grouped errors, and log streams in one local surface instead of splitting context across apps.
SQLite-backed history
Persist local runs long enough to compare behavior without needing a remote collector or a managed observability account.
Browser UI plus TUI
Use the browser when you want a richer inspection surface, and keep the terminal UI nearby for keyboard-first debugging.
Product tour
Follow a request from trace waterfall to grouped error.
The page below leans on real UI captures already in the repo so the product proof matches what Lantern actually ships today.
Trace waterfall
Inspect spans and request timing without leaving your local environment.
Log stream
Keep logs close to traces so debugging does not become a context switch.
Error groups
Cluster repeated failures into something you can triage quickly.
Install
Point your exporter at localhost and start capturing.
Lantern is intentionally simple to start because the biggest friction in observability tooling is setup cost before the first useful signal appears.
go install github.com/Meru143/lantern/cmd/lantern@latest
lantern serve --no-tui
export OTEL_EXPORTER_OTLP_ENDPOINT=http://localhost:4317
export OTEL_EXPORTER_OTLP_PROTOCOL=grpc
./your-appOpen http://localhost:4000
Inspect:
- traces
- logs
- services
- queries
- grouped errors