Portable, dependency-free C — the language that still runs on everything, and where its constraints become an advantage.
12 posts
A cross toolchain whose target triple differs from the host lets you build ARM binaries on an x86 box. I compile for armhf and aarch64, verify with file and readelf, hit the real Exec format error, and run it under qemu-user.
Hand-roll a lock-free SPSC ring buffer in C with atomic indices and acquire/release ordering. Real benchmarks, ThreadSanitizer race detection, and mutex comparison.
Fixed-point math on microcontrollers: why Q16.16 beats float when a chip has no FPU. Real C code, real overflow failures, a lookup-table sine, and honest timing numbers.
A hands-on guide to gdb for debugging C crashes: backtraces, core dumps, conditional breakpoints, watchpoints, threads, and the -O0 vs -O2 story — with real output from real programs.
A hands-on session with valgrind on Linux: real memcheck reports for memory leaks in C, invalid reads and writes, uninitialised values, plus massif heap profiles, callgrind instruction counts and helgrind data races — with actual output and the fixes.
Byte order explained with real programs: dumping a 32-bit integer on x86, htonl and network byte order, the raw-struct-over-a-socket bug, Modbus registers, and how to detect and byte-swap endianness.
Why C structs have holes: real sizeof/offsetof numbers, _Alignof, packed structs with a UBSan misaligned-load report, memcpy serialization garbage, and a false-sharing speedup measured on x86-64.
A hands-on tour of undefined behaviour in C: real AddressSanitizer and UBSan reports for out-of-bounds reads, use-after-free, signed overflow, bad shifts, null derefs and strict aliasing, each paired with a fix.
A superloop is fine for many devices, but one slow task starves the others. Real measurements of jitter and drift, plus the fixes that don't need an RTOS: fixed-timestep schedulers, state machines, and watchdogs.
A practical ESP32 vs ESP8266 buying guide for 2026: CPU, RAM, flash, Wi-Fi, BLE, GPIO, security, power, toolchains and price tiers, plus a decision table and concrete picks by use case — including when an ESP32-C3 is the right default.
A practical ESP-IDF tutorial for the ESP32-C3: choosing between Arduino, PlatformIO and ESP-IDF, installing the toolchain, the project layout, a minimal app_main, GPIO blink, UART logging and a working Wi-Fi station — with copyable commands.
ESPTier reimplements the EasyTier v2.6.4 wire protocol in plain C on an ESP32-C3 — TCP framing, SipHash-1-3 identity, AES-128-GCM, route sync and forwarding — so a constrained MCU becomes a real, pingable member of an overlay network.