This is the main repo for the project's smart contracts, with which we can store relatively big files (representing anything, legal documents, CVs, pdsfs.) onchain.
The core idea and innovation is based on the SSTORE2 library's READ & WRITE functions. It makes read and write operations at the fraction of the costs (of SLOAD, SSTORE).
What and how it is doing, please see the diagram below.
Reading data is a lot cheaper compared to native SLOAD operations (native solidity storage).
After reading 32 bytes SSTORE2.read becomes the cheaper option, and SSTORE2Map.read becomes cheaper when reading 33 bytes or more.
| Size (bytes) | SLOAD | SLOAD2 | SLOAD2 - Map | Savings | Savings (map) |
|---|---|---|---|---|---|
| 0 | 2.679 | 3.102 | 5.258 | 0,86x | 0,51x |
| 2 | 2.852 | 3.108 | 5.261 | 0,92x | 0,54x |
| 32 | 4.914 | 3.108 | 5.264 | 1,58x | 0,93x |
| 33 | 7.067 | 3.114 | 5.267 | 2,27x | 1,34x |
| 64 | 7.067 | 3.114 | 5.270 | 2,27x | 1,34x |
| 96 | 9.220 | 3.120 | 5.276 | 2,96x | 1,75x |
| 128 | 11.373 | 3.126 | 5.282 | 3,64x | 2,15x |
| 256 | 19.985 | 3.150 | 5.306 | 6,34x | 3,77x |
| 512 | 37.209 | 3.198 | 5.355 | 11,64x | 6,95x |
| 1024 | 71.659 | 3.296 | 5.454 | 21,74x | 13,14x |
| 24576 | 1.349.161 | 7.627 | 9.805 | 176,89x | 137,60x |
Writing data is also cheaper than native SSTORE operations (native solidity storage), but gains become apparent after higher data sizes.
After writing 32 bytes SSTORE2.write becomes the cheaper option, and SSTORE2Map.write becomes cheaper only when writing 128 bytes or more.
| Size (bytes) | SSTORE | SSTORE2 | SSTORE2 - Map | Savings | Savings (map) |
|---|---|---|---|---|---|
| 0 | 2.660 | 35.323 | 73.565 | 0,08x | 0,04x |
| 2 | 22.607 | 35.819 | 74.061 | 0,63x | 0,31x |
| 32 | 44.810 | 41.891 | 80.218 | 1,07x | 0,56x |
| 33 | 66.980 | 42.187 | 80.514 | 1,59x | 0,83x |
| 64 | 66.980 | 48.459 | 86.870 | 1,38x | 0,77x |
| 96 | 89.150 | 55.027 | 93.523 | 1,62x | 0,95x |
| 128 | 111.320 | 61.595 | 100.175 | 1,81x | 1,11x |
| 256 | 200.000 | 87.869 | 126.786 | 2,28x | 1,58x |
| 512 | 377.360 | 140.417 | 180.010 | 2,69x | 2,10x |
| 1024 | 732.080 | 245.522 | 286.475 | 2,98x | 2,56x |
| 24576 | 13.878.890 | 4.148.020 | 4.244.998 | 3,35x | 3,27x |
Notice: gas savings may change in future Ethereum hard-forks.
Notice x2: due to contract code limits 24576 bytes is the maximum amount of data that can be written in a single pointer / key. Attempting to write more will result in failure this is why the idea of writing large amount of data in chunks.
- Prerequisite: create a .env file with
- Clone this repository then install dependencies.
npm ci - Build contracts and generate typechain typeings.
npx hardhat compile - Run deployment script which will puts the deployments and the 2 files (1 image, 1 pdf) onto the mumbai network. (You can try matic as well).
npx hardhat run scripts/deploy.ts --network mumbai
You will need to create an .env file in the root directory. It needs to contain the following variables: