Case study · Systems debugging
Swift–C++ memory ownership and a four-day prototype
Three delivery strategies compared, a live encrypted-messaging demonstration in four days, and a root-cause fix instead of a rewrite.
- Swift
- C++
- Swift–C++ interoperability
- Memory management
- Encryption
- Rapid prototyping
Context and problem
Crypmoji built an encrypted-messaging product. Two problems arrived together — the company needed a live demonstration of encrypted messaging on a fixed deadline, and a memory defect in the Swift–C++ layer had persisted for about a year.
My role
As iOS Team Lead I framed the delivery options, aligned the team on one plan and led the build. I diagnosed and fixed the memory defect.
Alternatives and trade-offs
I laid out three delivery strategies for the proof of concept: a simulation, a full integration and a phased MVP. Comparing them side by side let the team agree on a plan that could deliver a live demonstration within four days.
Root cause
The defect came from unsafe ownership handoffs between Swift and C++ — objects crossing the language boundary without a clear owner. I removed those handoffs so ownership on each side of the boundary is explicit.
Results
The working demonstration was delivered in four days, and the ownership fix avoided a full rewrite of the affected code.