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+# How to generate test vectors
+
+You need to compile a version of `simd` locally and sign some transactions.
+It seems my printfs got committed into master somehow, so we have debug info without forking!
+
+The following was tested on `v0.40.0-rc0` of [`cosmos-sdk`](https://github.com/cosmos/cosmos-sdk).
+Just a little patch from my branch (which can be rebased).
+
+## Setup
+
+```
+git clone https://github.com/CosmWasm/cosmos-sdk.git
+cd cosmos-sdk
+git checkout cosmjs-test-vectors
+
+make build-simd-linux # or on OSX: make build-simd-darwin
+# this takes a while to download a docker image and make a deterministic build....
+
+ls -l ./build/simd
+./build/simd version
+# I got `goz-phase-1-706-g1a67086b6` for commit `1a67086b6`
+```
+
+**IMPORTANT** this stores the proper `simd` binary in `./build/simd`. You may well have another one
+in your global path, so calling `simd` instead of `./build/simd` may lead to confusing results.
+Please use the path to ensure the proper version.
+
+## Prepare the Keys
+
+You want to ensure you use the same keys as in the test vector,
+[taken from here](https://github.com/CosmWasm/cosmjs/blob/db1f183/packages/proto-signing/src/signing.spec.ts#L19-L27).
+This uses the testgen mnemonic:
+
+`economy stock theory fatal elder harbor betray wasp final emotion task crumble siren bottom lizard educate guess current outdoor pair theory focus wife stone`
+
+```
+./build/simd keys add testgen -i
+# enter mnemonic, and no passphrase
+
+./build/simd keys show -a testgen
+# cosmos1pkptre7fdkl6gfrzlesjjvhxhlc3r4gmmk8rs6
+
+./build/simd keys show testgen
+# this shows bech32 encoded pubkey!! (I think they need to fix that)
+```
+
+## Create the transactions
+
+First we create the unsigned transaction template we will be signing. We want to use the same flags as
+the testvectors create manually.
+
+```
+./build/simd tx bank send --generate-only --chain-id simd-testing --fees 2000ucosm $(./build/simd keys show -a testgen) cosmos1qypqxpq9qcrsszg2pvxq6rs0zqg3yyc5lzv7xu 1234567ucosm > unsigned_tx.json
+```
+
+This is what I get from `jq . unsigned_tx.json`, which is slightly different that the current test vector, in that
+I added a non-empty fee amount to properly test that:
+
+```json
+{
+  "body": {
+    "messages": [
+      {
+        "@type": "/cosmos.bank.v1beta1.MsgSend",
+        "from_address": "cosmos1pkptre7fdkl6gfrzlesjjvhxhlc3r4gmmk8rs6",
+        "to_address": "cosmos1qypqxpq9qcrsszg2pvxq6rs0zqg3yyc5lzv7xu",
+        "amount": [
+          {
+            "denom": "ucosm",
+            "amount": "1234567"
+          }
+        ]
+      }
+    ],
+    "memo": "",
+    "timeout_height": "0",
+    "extension_options": [],
+    "non_critical_extension_options": []
+  },
+  "auth_info": {
+    "signer_infos": [],
+    "fee": {
+      "amount": [
+        {
+          "denom": "ucosm",
+          "amount": "2000"
+        }
+      ],
+      "gas_limit": "200000",
+      "payer": "",
+      "granter": ""
+    }
+  },
+  "signatures": []
+}
+```
+
+## Generating Signatures
+
+All current test vectors were signed from account number 1, with increasing signatures (0, 1, 2).
+You can produce these with the following commands:
+
+```
+# you may not need `--home /tmp` but I got an odd error without it
+./build/simd tx sign --offline --sign-mode direct -a 1 -s 0 --from testgen --chain-id simd-testing unsigned_tx.json
+
+./build/simd tx sign --home /tmp --offline --sign-mode direct -a 1 -s 1 --from testgen --chain-id simd-testing unsigned_tx.json
+```
+
+You will get some output that looks more or less like this:
+
+```
+Sign Mode: SIGN_MODE_DIRECT
+
+Sign Bytes: 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
+
+Signature: c9dd20e07464d3a688ff4b710b1fbc027e495e797cfa0b4804da2ed117959227772de059808f765aa29b8f92edf30f4c2c5a438e30d3fe6897daa7141e3ce6f9
+
+Signed TX Bytes: 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
+
+{"body":{"messages":[{"@type":"/cosmos.bank.v1beta1.MsgSend","from_address":"cosmos1pkptre7fdkl6gfrzlesjjvhxhlc3r4gmmk8rs6","to_address":"cosmos1qypqxpq9qcrsszg2pvxq6rs0zqg3yyc5lzv7xu","amount":[{"denom":"ucosm","amount":"1234567"}]}],"memo":"","timeout_height":"0","extension_options":[],"non_critical_extension_options":[]},"auth_info":{"signer_infos":[{"public_key":{"@type":"/cosmos.crypto.secp256k1.PubKey","key":"A08EGB7ro1ORuFhjOnZcSgwYlpe0DSFjVNUIkNNQxwKQ"},"mode_info":{"single":{"mode":"SIGN_MODE_DIRECT"}},"sequence":"0"}],"fee":{"amount":[{"denom":"ucosm","amount":"2000"}],"gas_limit":"200000","payer":"","granter":""}},"signatures":["yd0g4HRk06aI/0txCx+8An5JXnl8+gtIBNou0ReVkid3LeBZgI92WqKbj5Lt8w9MLFpDjjDT/miX2qcUHjzm+Q=="]}
+```
+
+This should be enough to re-generate and update the test vectors as you wish.