3 ms·
Show HN: 106-byte JSON field extractor for embedded (8× smaller than JSMN)
Single-header JSON field extractor for when you control both message format and receiver.
106 bytes on ARM Cortex-M4, no malloc, MIT licensed.
#include "packet_atoms.h"
char temp[16];
jet("{\"temp\":22.5,\"hum\":65}", "temp", temp, sizeof(temp));
// temp now holds "22.5"
Deliberate limitations:
- Fixed field order (uses strstr)
- No nested objects/arrays
- Strings include quotes
- You design the protocol
Size comparison (ARM ‑Os):
- cJSON: 3.2 kB + malloc
- JSMN: 800 B + token iteration
- This: 106 B
Tested on Cortex-M4 and x86-64. Header-only, copy-paste ready.