import "github.com/opentracing/opentracing-go"
    import ".../some_tracing_impl"

    func main() {
        opentracing.SetGlobalTracer(
            // tracing impl specific:
            some_tracing_impl.New(...),
        )
        ...
    }

    func xyz(ctx context.Context, ...) {
        ...
        span, ctx := opentracing.StartSpanFromContext(ctx, "operation_name")
        defer span.Finish()
        span.LogFields(
            log.String("event", "soft error"),
            log.String("type", "cache timeout"),
            log.Int("waited.millis", 1500))
        ...
    }

    func xyz() {
        ...
        sp := opentracing.StartSpan("operation_name")
        defer sp.Finish()
        ...
    }

    func xyz(parentSpan opentracing.Span, ...) {
        ...
        sp := opentracing.StartSpan(
            "operation_name",
            opentracing.ChildOf(parentSpan.Context()))
        defer sp.Finish()
        ...
    }

    func makeSomeRequest(ctx context.Context) ... {
        if span := opentracing.SpanFromContext(ctx); span != nil {
            httpClient := &http.Client{}
            httpReq, _ := http.NewRequest("GET", "http://myservice/", nil)

            // Transmit the span's TraceContext as HTTP headers on our
            // outbound request.
            opentracing.GlobalTracer().Inject(
                span.Context(),
                opentracing.HTTPHeaders,
                opentracing.HTTPHeadersCarrier(httpReq.Header))

            resp, err := httpClient.Do(httpReq)
            ...
        }
        ...
    }

    http.HandleFunc("/", func(w http.ResponseWriter, req *http.Request) {
        var serverSpan opentracing.Span
        appSpecificOperationName := ...
        wireContext, err := opentracing.GlobalTracer().Extract(
            opentracing.HTTPHeaders,
            opentracing.HTTPHeadersCarrier(req.Header))
        if err != nil {
            // Optionally record something about err here
        }

        // Create the span referring to the RPC client if available.
        // If wireContext == nil, a root span will be created.
        serverSpan = opentracing.StartSpan(
            appSpecificOperationName,
            ext.RPCServerOption(wireContext))

        defer serverSpan.Finish()

        ctx := opentracing.ContextWithSpan(context.Background(), serverSpan)
        ...
    }

    func Customer(order *Order) log.Field {
        if os.Getenv("ENVIRONMENT") == "dev" {
            return log.String("customer", order.Customer.ID)
        }
        return log.Noop()
    }