Mars roadmaps and enhancement proposals

All proposals and roadmaps of Mars are listed here. Suggestions and discussions are sincerely welcomed.

Roadmaps
----------

DataFrame (Phase 1: #495, done)
Distributed engine (#493)

Enhancement Proposals
------------------------

### Project Galois (Towards Mars 1.0)

| Proposal | Status | Target milestone| Related PR |
| ------- | ------ | ------ | ------ |
| Project Galois (Towards Mars 1.0) (#1928) | Done | 0.7.0 | |
| Oscar: Mars actors 2.0 (#1935) | Done | 0.7.0 | #1925, #1916 |
| Mars storage lib (#1905) | Done | 0.7.0 | #1904 |
| New fusion strategy based on coloring algorithm (#2435) | Done | 0.9.0b1 | #2719 |
| Universal optimizer and smart fusion (#593) | WIP | | #598 |
| A speculative execution based task scheduler (#2575) | Done | 0.9.0rc1 | #2576 |
| DataFrame-oriented JIT Compiler (#2754) | WIP | | |
| Support more bands allocation strategies (#2787) | WIP | | |

### Accomplished and staled proposals

| Proposal | Status | Related PR |
| ------- | ------ | ------ |
| Standardize scheduler and worker APIs (#882) | Staled | |
| Mutable tensor (#415) | Done | #464, #536 |
| New mars.actors with multiple pluggable components (#584) | Staled| |
| Remote API (#1227) | Done | #1238, #1248, #1296 |
| Integrate with Ray (#1469) | Done | #1508, #1541 |
| `fetch_log` API (#1564) | Done | #1574 |

Start with CONTRIBUTING.rst and review the roadmap and enhancement proposal entries referenced in this issue. No implementation file, test, or concrete change is identified; completion would require defining the intended update and confirming the listed proposal statuses and related links.

Written by the indexing model from the issue text.