The Developer Tools Podcast with Fexingo: APIs, Infrastructure, and Software for Engineers

Lucas and Luna dig into the unsung hero of API reliability: rate limiting. They explain why a naive rate limit can be worse than none, using the example of a massive outage at a well-known developer tool in early 2026. Lucas walks through leaky bucket vs. token bucket algorithms, and Luna presses on why 429s aren't always a bad thing. They debate the trade-offs between strict limits and burst allo...

Most engineers treat API gateways as a simple routing layer. But a poorly configured gateway can add 200-500 milliseconds of overhead per request—and when multiplied across millions of requests daily, that latency cost is staggering. Lucas and Luna break down the hidden latency bottleneck introduced by Kong and AWS API Gateway, using a real case from a fintech startup that cut P99 latency by 42 pe...

Lucas and Luna dissect a specific silent failure pattern in modern APIs: the 200 OK response that contains a business-level error. Using Stripe's idempotency keys and GitHub's merge conflict response as concrete examples, they explore why HTTP status codes alone are not enough for reliable integrations. The episode covers how Twilio's API design team built 'semantic error codes' into their v2 spec...

In the debut episode of The Developer Tools Podcast, Lucas and Luna unpack why Stripe's API documentation is considered the gold standard in developer experience. They break down the specific design choices — from idempotency keys to clear error messages — that turned a payments API into a platform developers genuinely enjoy using. Along the way, they discuss what other dev-tool companies can lear...