SigNoz

An open-source APM and observability platform — a self-hosted alternative to Datadog, New Relic, and Dynatrace. SigNoz unifies traces, metrics, and logs in a single UI built natively on OpenTelemetry, using ClickHouse for high-performance analytical queries.

What is SigNoz?

SigNoz was founded in 2021 as a fully open-source alternative to commercial APM tools. The key architectural decision is using ClickHouse — a columnar OLAP database — as the unified storage for traces, metrics, and logs. This enables sub-second query performance for analytical queries like "show me all traces for the payment service with P99 latency above 2 seconds in the last hour" across billions of spans.

Unlike the Grafana + Jaeger + Prometheus stack, SigNoz provides native correlation: click a latency spike on a metrics chart and instantly see the related traces. Click a trace to see the correlated logs from the same service and time window. This "three-signal correlation" eliminates the context-switching that makes debugging slow in modular stacks.

Quick Start (Docker Compose)

# SigNoz — Docker Compose install
git clone -b main https://github.com/SigNoz/signoz.git
cd signoz/deploy/
docker compose -f docker/clickhouse-setup/docker-compose.yaml up -d

# Services started:
# - SigNoz UI:          http://localhost:3301
# - OTLP gRPC:          :4317
# - OTLP HTTP:          :4318
# - Query service:      :8080
# - ClickHouse:         :9000

# Default login: [email protected] / password

Node.js Instrumentation

// Node.js — send traces to SigNoz
import { NodeSDK } from '@opentelemetry/sdk-node';
import { OTLPTraceExporter } from '@opentelemetry/exporter-trace-otlp-http';
import { getNodeAutoInstrumentations } from '@opentelemetry/auto-instrumentations-node';

const sdk = new NodeSDK({
  traceExporter: new OTLPTraceExporter({
    url: 'http://signoz-otel-collector:4318/v1/traces',
    headers: {
      // SigNoz Cloud requires the ingestion key
      // 'signoz-ingestion-key': process.env.SIGNOZ_INGESTION_KEY,
    },
  }),
  instrumentations: [getNodeAutoInstrumentations()],
});
sdk.start();

Python / FastAPI Instrumentation

# Python — OpenTelemetry + SigNoz
pip install opentelemetry-sdk   opentelemetry-exporter-otlp   opentelemetry-instrumentation-fastapi   opentelemetry-instrumentation-sqlalchemy

# main.py
from opentelemetry import trace
from opentelemetry.sdk.trace import TracerProvider
from opentelemetry.sdk.trace.export import BatchSpanProcessor
from opentelemetry.exporter.otlp.proto.http.trace_exporter import OTLPSpanExporter
from opentelemetry.instrumentation.fastapi import FastAPIInstrumentor

trace.set_tracer_provider(TracerProvider())
trace.get_tracer_provider().add_span_processor(
    BatchSpanProcessor(OTLPSpanExporter(
        endpoint="http://signoz-otel-collector:4318/v1/traces"
    ))
)
FastAPIInstrumentor.instrument_app(app)  # auto-instrument FastAPI

Alert Rules

# SigNoz alert rule (YAML format for API / import)
{
  "alert": "HighP99Latency",
  "expr": "histogram_quantile(0.99, sum(rate(signoz_latency_bucket{service_name='payment-service'}[5m])) by (le)) > 2",
  "for": "5m",
  "labels": {
    "severity": "critical",
    "team": "backend"
  },
  "annotations": {
    "summary": "P99 latency above 2s for payment-service",
    "runbook": "https://wiki.internal/runbooks/payment-latency"
  }
}