@startuml
scale 820 width
left to right direction
skinparam backgroundColor transparent
skinparam shadowing false
skinparam defaultFontName Monospace
skinparam defaultFontSize 9
skinparam rectangleBorderColor #2c7794
skinparam rectangleBackgroundColor #edf6fa
skinparam ArrowColor #8095a1
title A7 RUNTIME — one artifact, two checkpoints, one proof

rectangle "<<source>>\n01 task03 C\nA/B/C experiment" as SRC
rectangle "<<artifact>>\n02 ELF + image\nheap_4 symbols" as ELF
rectangle "<<checkpoint E01>>\n03 fragmented\nblocks=2 · aligned=1" as E1
rectangle "<<memory>>\n04 ucHeap[4096]\nheaders + payload" as MEM
rectangle "<<checkpoint E02>>\n05 coalesced\nfinal=initial · blocks=1\nOOM=1 · PASS=1" as E2

SRC --> ELF : compile + link
ELF --> E1 : reset / load / replay
E1 --> MEM : inspect bytes
MEM --> E2 : continue
@enduml