Developer builds satellite daemon in Crystal, flags five language pitfalls worth knowing

A developer built a satellite ground station daemon called Kozai using the Crystal programming language, producing a fully static binary of under 7 MB with zero runtime dependencies. The project relied on just six standard library modules and required no build steps beyond the crystal build command, making deployment as simple as a single scp transfer. Testing revealed that Crystal's suffix rescue syntax silently catches all exceptions rather than filtering by type, a subtle but dangerous behavior inherited from Ruby that the developer only caught using the Ameba linter. Apparent memory growth during load testing initially looked like a leak but turned out to be Crystal's fiber stack pooling behavior, with memory stabilizing after an initial ramp-up rather than growing indefinitely. The developer concluded that RSS-based memory monitoring is misleading with Crystal's Boehm GC and recommends checking for a plateau rather than zero growth as the correct acceptance criterion.