https://company-engineering.pages.dev/tags/reliability/Recent content in Reliability on Company EngineeringHugoenMon, 01 Jun 2026 00:00:00 +0000https://company-engineering.pages.dev/posts/designing-reliable-data-synchronization-at-scale/Mon, 01 Jun 2026 00:00:00 +0000https://company-engineering.pages.dev/posts/designing-reliable-data-synchronization-at-scale/<p>Keeping data consistent across systems we don&rsquo;t control is one of the hardest problems we work on. Every external integration is a small distributed system: networks fail, third-party APIs rate-limit us, and the &ldquo;source of truth&rdquo; is often whichever side wrote last. This post covers the patterns we lean on to make synchronization predictable rather than heroic.</p> <h2 id="the-shape-of-the-problem">The shape of the problem</h2> <p>A sync flow looks deceptively simple: read from a source, transform, write to a destination. In practice each step can fail independently, and the same change can arrive more than once. We design every flow around three assumptions:</p>