Picking a Translation API for a Real-Time SaaS Feature
Adding real-time translation to a SaaS product looks like a straightforward API-integration task until you actually compare providers against what an in-product feature needs, which is a different set of priorities than translating a document.
Latency matters more than marginal quality differences
For a document translated once and read later, translation quality is the dominant factor. For a real-time in-product feature — a chat message, a live caption, a comment translated on the fly — latency is often the deciding factor, because a translation that arrives after the user has already moved on isn't useful regardless of how accurate it is. It's worth benchmarking actual round-trip latency under realistic request sizes before comparing quality scores, since the provider with the best benchmark quality isn't always the one with usable latency for a live feature.
Per-character pricing changes the calculation at volume
Most translation APIs price per character, and that cost scales linearly with usage in a way that's easy to underestimate at pilot scale and painful to discover at production scale. Modeling cost against realistic monthly volume — not a demo's worth of requests — before committing to a provider avoids finding out the pricing model doesn't fit the product until after it's already integrated.
Language coverage isn't uniform across providers
Coverage and quality both vary significantly by language pair, and a provider that's excellent for major European languages can be noticeably weaker for less common language pairs relevant to a specific user base. Testing against the actual language pairs the product needs — not just checking a language is "supported" — catches quality gaps a generic comparison chart won't show.
Build the integration so the provider isn't a permanent commitment
Because pricing, latency, and quality all shift over time as providers update their models, it's worth architecting the integration behind a thin internal interface rather than calling a specific provider's SDK directly throughout the codebase. That one decision is what makes switching providers later a configuration change instead of a rewrite, if the tradeoffs that mattered at launch stop being the right ones a year in.