Observability and SRE Guide for Developers

When something breaks at night, you need to see what your system is doing. This guide covers the three pillars, then SLOs, alerting, incidents and the patterns that keep a service up.

The examples were run on a local machine, and the output you see is real.

Who it is for: Back-end and DevOps developers who run services in production, and candidates who get monitoring and reliability questions.

9 lessons · Published by Jainik · Last updated

1. See your system

  1. 1. Observability & SRE · 12 min
    What Observability Is and the Three Pillars

    Monitoring versus observability, logs, metrics and traces, the questions each answers, and the golden signals.

  2. 2. Observability & SRE · 14 min
    Logging That Helps: Structured Logs, Levels and Correlation IDs

    Structured JSON logs, levels, what to log and not log, correlation IDs across services, and sampling.

2. Metrics and traces

  1. 3. Observability & SRE · 15 min
    Metrics and Prometheus: Counters, Gauges, Histograms and Percentiles

    The metric types, labels and cardinality, why averages lie, percentiles, and a real Prometheus scrape of a Node service.

  2. 4. Observability & SRE · 15 min
    Distributed Tracing With OpenTelemetry

    Spans and traces, context propagation, instrumenting a Node service, and reading a trace to find a slow call.

3. Reliability targets

  1. 5. Observability & SRE · 14 min
    SLIs, SLOs and Error Budgets

    Choosing indicators, setting objectives, how nines translate to minutes, burn rates and what error budgets are for.

  2. 6. Observability & SRE · 13 min
    Alerting and Dashboards That People Trust

    Alerting on symptoms, avoiding alert fatigue, runbooks, dashboard design, and burn-rate alerts with a worked example.

4. When things fail

  1. 7. Observability & SRE · 14 min
    Incidents, On-Call and Blameless Post-Mortems

    Incident roles and the first hour, communication, on-call habits, writing a blameless post-mortem with a full example.

  2. 8. Observability & SRE · 15 min
    Reliability Patterns: Timeouts, Retries, Circuit Breakers and Graceful Degradation

    Failure modes, timeouts and retries with backoff, circuit breakers, bulkheads, load shedding, tested with fault injection.

5. Interview practice

  1. 9. Observability & SRE · 14 min
    Observability and SRE Interview Questions With Model Answers

    Questions on monitoring, SLOs, incidents and reliability with model answers.

More reading orders are on the guides page, and every series is listed on the home page.