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README.md

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+## Build
+```
+git clone https://github.com/tevador/monero-seed.git
+cd monero-seed
+cmake ..
+make
+```
+
+## Usage
+
+### Create a new seed
+
+The sole argument is the wallet creation date in `yyyy/MM/dd` format.
+```
+> ./monero-seed --create 2100/03/14
+Mnemonic phrase: pumpkin alter spice lend position sentence surface snow atom lobster exotic robot profit chase
+- version: 1
+- private key: a147f59c9b80e77824ba2e44241598b3b9ddf2e6458e9970352894216b9cbbba
+- created on or after: 02/Mar/2100
+```
+
+### Restore seed
+
+```
+> ./monero-seed --restore "pumpkin alter spice lend position sentence surface snow atom lobster exotic robot profit chase"
+- version: 1
+- private key: a147f59c9b80e77824ba2e44241598b3b9ddf2e6458e9970352894216b9cbbba
+- created on or after: 02/Mar/2100
+```
+
+Restore has limited error correction capability, namely it can correct a single erasure (illegible symbol with a known location).
+This can be tested by replacing a word with `xxxx`:
+
+```
+> ./monero-seed --restore "pumpkin alter xxxx lend position sentence surface snow atom lobster exotic robot profit chase"
+Warning: corrected erasure: xxxx -> spice
+- version: 1
+- private key: a147f59c9b80e77824ba2e44241598b3b9ddf2e6458e9970352894216b9cbbba
+- created on or after: 02/Mar/2100
+```
+
+## Implementation details
+
+The mnemonic phrase contains 154 bits of data, which are used as follows:
+
+* 3 bits for version (this allows the format to be updated up to 7 times)
+* 2 bits reserved for future use
+* 10 bits for approximate wallet creation date
+* 128 bits for the private key seed
+* 11 bits for error detection/correction
+
+### Wordlist
+
+Uses the wordlist from BIP-39. It has 2048 words, allowing 11 bits to be stored in each word. It has some additional useful properties,
+for example each word can be uniquly identified by its first 4 characters.
+
+### Wallet creation date
+
+The mnemonic phrase doesn't store block height, but the time when the wallet was created. This allows the seed to be generated
+offline without access to the blockchain. Wallet software can easily convert a date to the corresponding block height when restoring a seed.
+The wallet creation date has a resolution of 2629746 seconds (1/12 of the average Gregorian year). All dates between June 2020
+and September 2105 can be represented.
+
+### Private key seed
+
+The private key is generated by wallet software from the 128-bit seed included in the mnemonic phrase. Argon2id is used as KDF (memory = 256 MB). The wallet creation date is used as a salt. 128-bit seed provides the same level of security as the elliptic curve used by Monero.
+
+### Error detection/correction
+
+The mnemonic phrase can be treated as a polynomial over GF(2048), which allows us to use an efficient Reed-Solomon ECC with one check word. All single-word errors can be detected and all single-word erasures can be corrected.