1. TL;DR
2. 1. What is arena allocator
3. 2. Intrusive data structures
4. 1. 2.1. Single linked list
   2. 2.2. Double linked list
   3. 2.3. Hashmaps
   4. 2.4. Dynamic consecutive arrays
5. 3. Allocator implementation
6. 4. AST nodes
7. 5. #![no_std]
8. 6. Benchmarks
9. 7. Flamegraphs
10. 8. Memory usage optimisations
11. 9. AST caching