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https://github.com/tqtezos/priced-event-oracle

An oracle contract that accepts queries for a Tez price
https://github.com/tqtezos/priced-event-oracle

Last synced: 5 days ago
JSON representation

An oracle contract that accepts queries for a Tez price

Host: GitHub
URL: https://github.com/tqtezos/priced-event-oracle
Owner: tqtezos
License: bsd-3-clause
Created: 2021-03-10T21:52:14.000Z (over 3 years ago)
Default Branch: master
Last Pushed: 2021-07-21T01:48:49.000Z (over 3 years ago)
Last Synced: 2024-08-01T22:44:40.985Z (3 months ago)
Language: Haskell
Size: 29.3 KB
Stars: 2
Watchers: 4
Forks: 0
Open Issues: 2
Metadata Files:
- Readme: README.md
- License: LICENSE

Awesome Lists containing this project

README

# Priced Event Oracle

This repo includes the _Priced Event Oracle_, an implementation of a
two-way priced oracle that uses off-chain events to return data to the caller:

```haskell
parameter (or (pair %ask (contract (pair string
nat))
string)
(lambda %admin (pair address
mutez)
(pair (list operation)
(pair address
mutez))));
storage (pair (address %owner)
(mutez %price));
```

### Contract source

The Michelson source for this contract and any variants may be found in
[/contracts](/contracts).

## Specification

The contract stores its administrator `(address %owner)` and the current
`(mutez price)`.

It has two entrypoints:
- `ask`
* Accepts a `pair` of:
+ The "return" or callback `contract` reference: `(contract (pair string nat))`
+ The query as a `string`
* Rejects any calls that do not transfer the exact `price` in Tez to the contract
- `admin`
* Accepts a `lambda` whose:
+ Input is the current `owner` `address` and `price` in `mutez`
+ Output is the new `owner`, new `price`, and any `operation`'s to emit
* Rejects any `SENDER` other than the `owner`

## Use

1. A user calls the `ask` entrypoint with his `query` `string` and callback
`contract` reference
2. An off-chain indexer detects the `ask` contract call and calculates a response
3. The oracle's host calls the `contract` reference from the `ask` with the
`pair` of:
- `(string %query_response)`
- `(nat %counter)`
+ Used to distinguish responses to a repeated query
+ Equal to the number of _previously completed_ responses to this `query`
and `contract`, i.e. it's `0` for the first response to a pair of `query`,
`contract (pair string nat)`, `1` for the second response, etc.

## Verification

This contract has a formal proof in Coq using Mi-Cho-Coq.

A merge request containing it may be found [here](https://gitlab.com/tqgroup/mi-cho-coq/-/merge_requests/1).

## Demo on Delphinet

Contract on Delphi [better-call.dev](https://better-call.dev/delphinet/KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm/operations)

Originate:

```bash
❯❯❯ alpha-client --wait none originate contract LambdaAdminOracle3 \
transferring 0 from $BOB_ADDRESS running \
"$(cat lambda_admin_oracle_2.tz | tr -d '\n')" \
--init "(Pair \"$BOB_ADDRESS\" 1)" \
--burn-cap 0.127
Waiting for the node to be bootstrapped before injection...
Current head: BMAk1ar2GRSF (timestamp: 2021-02-03T22:32:57-00:00, validation: 2021-02-03T22:33:15-00:00)
Node is bootstrapped, ready for injecting operations.
Estimated gas: 2483.822 units (will add 100 for safety)
Estimated storage: 508 bytes added (will add 20 for safety)
Operation successfully injected in the node.
Operation hash is 'opRb971eCbVJb9ZSU22Go4GKLtPDWUBJSXiWGSbkaZnvZLLk6a3'
NOT waiting for the operation to be included.
Use command
tezos-client wait for opRb971eCbVJb9ZSU22Go4GKLtPDWUBJSXiWGSbkaZnvZLLk6a3 to be included --confirmations 30 --branch BMAk1ar2GRSFZQig3bcycqn865URmnY1jBjnYmZJ6Wg6x2puDgH
and/or an external block explorer to make sure that it has been included.
This sequence of operations was run:
Manager signed operations:
From: tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm
Fee to the baker: ꜩ0.000753
Expected counter: 526617
Gas limit: 2584
Storage limit: 528 bytes
Balance updates:
tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm ............. -ꜩ0.000753
fees(tz1Ke2h7sDdakHJQh8WX4Z372du1KChsksyU,204) ... +ꜩ0.000753
Origination:
From: tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm
Credit: ꜩ0
Script:
{ parameter
(or (pair %ask (contract (pair string nat)) string)
(lambda %admin (pair address mutez) (pair (list operation) (pair address mutez)))) ;
storage (pair (address %owner) (mutez %price)) ;
code { DUP ;
CDR ;
SWAP ;
CAR ;
IF_LEFT
{ DROP ;
DUP ;
CDR ;
AMOUNT ;
COMPARE ;
EQ ;
IF { NIL operation ; PAIR } { PUSH string "wrong price" ; FAILWITH } }
{ SWAP ;
DUP ;
CAR ;
SENDER ;
COMPARE ;
EQ ;
IF { EXEC } { PUSH string "not admin" ; FAILWITH } } } }
Initial storage: (Pair "tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm" 1)
No delegate for this contract
This origination was successfully applied
Originated contracts:
KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm
Storage size: 251 bytes
Paid storage size diff: 251 bytes
Consumed gas: 2483.822
Balance updates:
tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm ... -ꜩ0.06275
tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm ... -ꜩ0.06425

New contract KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm originated.
Contract memorized as LambdaAdminOracle3.
```

Ask:

```bash
~/C/m/lorentz-contract-vesting ❯❯❯ alpha-client --wait none transfer 0.000001 from $BOB_ADDRESS to KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm \
--entrypoint ask --arg 'Pair "KT1HHgfN2v47ogDikDLRKigaXaDAW2rSdyk9" "my_query"'
Waiting for the node to be bootstrapped before injection...
Current head: BLL1JWxNy3QR (timestamp: 2021-02-03T22:34:27-00:00, validation: 2021-02-03T22:34:35-00:00)
Node is bootstrapped, ready for injecting operations.
Estimated gas: 4050.339 units (will add 100 for safety)
Estimated storage: no bytes added
Operation successfully injected in the node.
Operation hash is 'ookvVazPMc8cDPPVmqLopdHWG5yWyFWnSTHKH8rv8ixGCnjyFrQ'
NOT waiting for the operation to be included.
Use command
tezos-client wait for ookvVazPMc8cDPPVmqLopdHWG5yWyFWnSTHKH8rv8ixGCnjyFrQ to be included --confirmations 30 --branch BLL1JWxNy3QRSskj12b7fgLiutntgoruJjhEuCw3D5iYibYwfrc
and/or an external block explorer to make sure that it has been included.
This sequence of operations was run:
Manager signed operations:
From: tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm
Fee to the baker: ꜩ0.000731
Expected counter: 526618
Gas limit: 4151
Storage limit: 0 bytes
Balance updates:
tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm ............. -ꜩ0.000731
fees(tz1Ke2h7sDdakHJQh8WX4Z372du1KChsksyU,204) ... +ꜩ0.000731
Transaction:
Amount: ꜩ0.000001
From: tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm
To: KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm
Entrypoint: ask
Parameter: (Pair "KT1HHgfN2v47ogDikDLRKigaXaDAW2rSdyk9" "my_query")
This transaction was successfully applied
Updated storage:
(Pair 0x0000aad02222472cdf9892a3011c01caf6407f027081 1)
Storage size: 251 bytes
Consumed gas: 4050.339
Balance updates:
tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm ... -ꜩ0.000001
KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm ... +ꜩ0.000001
```

Make Fred the owner:

```bash
❯❯❯ alpha-client --wait none transfer 0 from $BOB_ADDRESS to KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm \
--entrypoint admin --arg '{ CDR; PUSH address "tz1RwoEdg4efDQHarsw6aKtMUYvg278Gv1ir"; PAIR; NIL operation; PAIR }'
Waiting for the node to be bootstrapped before injection...
Current head: BLXqbDdeAiFa (timestamp: 2021-02-03T22:45:47-00:00, validation: 2021-02-03T22:46:14-00:00)
Node is bootstrapped, ready for injecting operations.
Estimated gas: 3550.653 units (will add 100 for safety)
Estimated storage: no bytes added
Operation successfully injected in the node.
Operation hash is 'op1QEQKK2JuCf6MfDDMT76ZYiicWQ9AJiX6uF1z3TVu82xBd3mp'
NOT waiting for the operation to be included.
Use command
tezos-client wait for op1QEQKK2JuCf6MfDDMT76ZYiicWQ9AJiX6uF1z3TVu82xBd3mp to be included --confirmations 30 --branch BLXqbDdeAiFa91V3B3mbqxt977SU9q673QpnahJtNQ9AjFjj9C5
and/or an external block explorer to make sure that it has been included.
This sequence of operations was run:
Manager signed operations:
From: tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm
Fee to the baker: ꜩ0.000687
Expected counter: 526619
Gas limit: 3651
Storage limit: 0 bytes
Balance updates:
tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm ............. -ꜩ0.000687
fees(tz1Ke2h7sDdakHJQh8WX4Z372du1KChsksyU,204) ... +ꜩ0.000687
Transaction:
Amount: ꜩ0
From: tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm
To: KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm
Entrypoint: admin
Parameter: { CDR ;
PUSH address "tz1RwoEdg4efDQHarsw6aKtMUYvg278Gv1ir" ;
PAIR ;
NIL operation ;
PAIR }
This transaction was successfully applied
Updated storage:
(Pair 0x0000452d024b72d5897f14a02dc1a3b8e012c802cc3d 1)
Storage size: 251 bytes
Consumed gas: 3550.653
```

Set the price to `2 mutez`:

```bash
❯❯❯ alpha-client --wait none transfer 0 from $BOB_ADDRESS to KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm \
--entrypoint admin --arg '{ CAR; PUSH mutez 2; SWAP; PAIR; NIL operation; PAIR }'
Waiting for the node to be bootstrapped before injection...
Current head: BKvisxu111qX (timestamp: 2021-02-03T22:48:47-00:00, validation: 2021-02-03T22:49:05-00:00)
Node is bootstrapped, ready for injecting operations.
This simulation failed:
Manager signed operations:
From: tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm
Fee to the baker: ꜩ0
Expected counter: 526620
Gas limit: 1040000
Storage limit: 60000 bytes
Transaction:
Amount: ꜩ0
From: tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm
To: KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm
Entrypoint: admin
Parameter: { CAR ; PUSH mutez 2 ; SWAP ; PAIR ; NIL operation ; PAIR }
This operation FAILED.

Runtime error in contract KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm:
01: { parameter
02: (or (pair %ask (contract (pair string nat)) string)
03: (lambda %admin (pair address mutez) (pair (list operation) (pair address mutez)))) ;
04: storage (pair (address %owner) (mutez %price)) ;
05: code { DUP ;
06: CDR ;
07: SWAP ;
08: CAR ;
09: IF_LEFT
10: { DROP ;
11: DUP ;
12: CDR ;
13: AMOUNT ;
14: COMPARE ;
15: EQ ;
16: IF { NIL operation ; PAIR } { PUSH string "wrong price" ; FAILWITH } }
17: { SWAP ;
18: DUP ;
19: CAR ;
20: SENDER ;
21: COMPARE ;
22: EQ ;
23: IF { EXEC } { PUSH string "not admin" ; FAILWITH } } } }
At line 23 characters 53 to 61,
script reached FAILWITH instruction
with "not admin"
Fatal error:
transfer simulation failed
```

But Bob is no longer the admin, so this fails:

Fred can update it to `2 mutez`, however:

```bash
❯❯❯ alpha-client --wait none transfer 0 from $FRED_ADDRESS to KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm \
--entrypoint admin --arg '{ CAR; PUSH mutez 2; SWAP; PAIR; NIL operation; PAIR }'
Waiting for the node to be bootstrapped before injection...
Current head: BKwRQxtfx6oY (timestamp: 2021-02-03T22:51:37-00:00, validation: 2021-02-03T22:51:50-00:00)
Node is bootstrapped, ready for injecting operations.
Estimated gas: 3499.533 units (will add 100 for safety)
Estimated storage: no bytes added
Operation successfully injected in the node.
Operation hash is 'opQKw7eAnahYi6NFsgCMbqeU6RfQ89k9Y2R7BEvWwU4pAAnnZCr'
NOT waiting for the operation to be included.
Use command
tezos-client wait for opQKw7eAnahYi6NFsgCMbqeU6RfQ89k9Y2R7BEvWwU4pAAnnZCr to be included --confirmations 30 --branch BKwRQxtfx6oYTdPqAQP4RAqqkAQfS4Ar15uj1xsHcnGLFmo6oLo
and/or an external block explorer to make sure that it has been included.
This sequence of operations was run:
Manager signed operations:
From: tz1RwoEdg4efDQHarsw6aKtMUYvg278Gv1ir
Fee to the baker: ꜩ0.001259
Expected counter: 1242109
Gas limit: 10000
Storage limit: 0 bytes
Balance updates:
tz1RwoEdg4efDQHarsw6aKtMUYvg278Gv1ir ............. -ꜩ0.001259
fees(tz1Ke2h7sDdakHJQh8WX4Z372du1KChsksyU,204) ... +ꜩ0.001259
Revelation of manager public key:
Contract: tz1RwoEdg4efDQHarsw6aKtMUYvg278Gv1ir
Key: edpkvMCwX3MyDg92HckSwFVofR8hcZEjAqrhWJ8SGQgkGjgK1V1gPo
This revelation was successfully applied
Consumed gas: 1000
Manager signed operations:
From: tz1RwoEdg4efDQHarsw6aKtMUYvg278Gv1ir
Fee to the baker: ꜩ0.000548
Expected counter: 1242110
Gas limit: 3600
Storage limit: 0 bytes
Balance updates:
tz1RwoEdg4efDQHarsw6aKtMUYvg278Gv1ir ............. -ꜩ0.000548
fees(tz1Ke2h7sDdakHJQh8WX4Z372du1KChsksyU,204) ... +ꜩ0.000548
Transaction:
Amount: ꜩ0
From: tz1RwoEdg4efDQHarsw6aKtMUYvg278Gv1ir
To: KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm
Entrypoint: admin
Parameter: { CAR ; PUSH mutez 2 ; SWAP ; PAIR ; NIL operation ; PAIR }
This transaction was successfully applied
Updated storage:
(Pair 0x0000452d024b72d5897f14a02dc1a3b8e012c802cc3d 2)
Storage size: 251 bytes
Consumed gas: 3499.533
```

Bob now tries to ask with only `1 mutez`:

```bash
❯❯❯ alpha-client --wait none transfer 0.000001 from $BOB_ADDRESS to KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm \
--entrypoint ask --arg 'Pair "KT1HHgfN2v47ogDikDLRKigaXaDAW2rSdyk9" "my_query"'
Waiting for the node to be bootstrapped before injection...
Current head: BMAT8i5MGPt2 (timestamp: 2021-02-03T22:53:37-00:00, validation: 2021-02-03T22:53:53-00:00)
Node is bootstrapped, ready for injecting operations.
This simulation failed:
Manager signed operations:
From: tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm
Fee to the baker: ꜩ0
Expected counter: 526620
Gas limit: 1040000
Storage limit: 60000 bytes
Transaction:
Amount: ꜩ0.000001
From: tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm
To: KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm
Entrypoint: ask
Parameter: (Pair "KT1HHgfN2v47ogDikDLRKigaXaDAW2rSdyk9" "my_query")
This operation FAILED.

Runtime error in contract KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm:
01: { parameter
02: (or (pair %ask (contract (pair string nat)) string)
03: (lambda %admin (pair address mutez) (pair (list operation) (pair address mutez)))) ;
04: storage (pair (address %owner) (mutez %price)) ;
05: code { DUP ;
06: CDR ;
07: SWAP ;
08: CAR ;
09: IF_LEFT
10: { DROP ;
11: DUP ;
12: CDR ;
13: AMOUNT ;
14: COMPARE ;
15: EQ ;
16: IF { NIL operation ; PAIR } { PUSH string "wrong price" ; FAILWITH } }
17: { SWAP ;
18: DUP ;
19: CAR ;
20: SENDER ;
21: COMPARE ;
22: EQ ;
23: IF { EXEC } { PUSH string "not admin" ; FAILWITH } } } }
At line 16 characters 71 to 79,
script reached FAILWITH instruction
with "wrong price"
Fatal error:
transfer simulation failed
```

But it fails, since the price has been updated to `2 mutez`.

Bob then tries to ask with `2 mutez`:

```bash
❯❯❯ alpha-client --wait none transfer 0.000002 from $BOB_ADDRESS to KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm \
--entrypoint ask --arg 'Pair "KT1HHgfN2v47ogDikDLRKigaXaDAW2rSdyk9" "my_query"'
Waiting for the node to be bootstrapped before injection...
Current head: BLTJP9yYX7aP (timestamp: 2021-02-03T22:54:37-00:00, validation: 2021-02-03T22:54:58-00:00)
Node is bootstrapped, ready for injecting operations.
Estimated gas: 4050.339 units (will add 100 for safety)
Estimated storage: no bytes added
Operation successfully injected in the node.
Operation hash is 'opMaxM1iqD8SbzYd9URMPnXG8jZDXRUDSo3mrYH4K5g52tui9yX'
NOT waiting for the operation to be included.
Use command
tezos-client wait for opMaxM1iqD8SbzYd9URMPnXG8jZDXRUDSo3mrYH4K5g52tui9yX to be included --confirmations 30 --branch BLTJP9yYX7aPea6unhsvzJwKYRvUZuh7Wpqjx6GAJmgoLyingDM
and/or an external block explorer to make sure that it has been included.
This sequence of operations was run:
Manager signed operations:
From: tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm
Fee to the baker: ꜩ0.000731
Expected counter: 526620
Gas limit: 4151
Storage limit: 0 bytes
Balance updates:
tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm ............. -ꜩ0.000731
fees(tz1Ke2h7sDdakHJQh8WX4Z372du1KChsksyU,204) ... +ꜩ0.000731
Transaction:
Amount: ꜩ0.000002
From: tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm
To: KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm
Entrypoint: ask
Parameter: (Pair "KT1HHgfN2v47ogDikDLRKigaXaDAW2rSdyk9" "my_query")
This transaction was successfully applied
Updated storage:
(Pair 0x0000452d024b72d5897f14a02dc1a3b8e012c802cc3d 2)
Storage size: 251 bytes
Consumed gas: 4050.339
Balance updates:
tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm ... -ꜩ0.000002
KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm ... +ꜩ0.000002
```

And it succeeds.

We can now verify that the oracle contract holds `3 mutez`:

```bash
❯❯❯ alpha-client get balance for KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm

0.000003 ꜩ
```

Fred decides to send the entire balance to Bob:

```bash
❯❯❯ alpha-client --wait none transfer 0 from $FRED_ADDRESS to KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm \
--entrypoint admin --arg "{ NIL operation; PUSH address \"$BOB_ADDRESS\"; CONTRACT unit; IF_NONE { PUSH string \"not receiver\";FAILWITH } { PUSH mutez 3;UNIT;TRANSFER_TOKENS;CONS;PAIR } }"

Waiting for the node to be bootstrapped before injection...
Current head: BMS2Vkyw5Bgq (timestamp: 2021-02-03T23:00:08-00:00, validation: 2021-02-03T23:00:23-00:00)
Node is bootstrapped, ready for injecting operations.
Estimated gas: 5414.383 units (will add 100 for safety)
Estimated storage: no bytes added
Operation successfully injected in the node.
Operation hash is 'onhhCv9Fshn73KbDosiYRnZvov29xCcYmNduzE4hCtNzU8awszW'
NOT waiting for the operation to be included.
Use command
tezos-client wait for onhhCv9Fshn73KbDosiYRnZvov29xCcYmNduzE4hCtNzU8awszW to be included --confirmations 30 --branch BMS2Vkyw5BgqpdHnp2SNwmrR8LSukTh7fgiVsisSTAW8zorsh38
and/or an external block explorer to make sure that it has been included.
This sequence of operations was run:
Manager signed operations:
From: tz1RwoEdg4efDQHarsw6aKtMUYvg278Gv1ir
Fee to the baker: ꜩ0.00092
Expected counter: 1242111
Gas limit: 5515
Storage limit: 0 bytes
Balance updates:
tz1RwoEdg4efDQHarsw6aKtMUYvg278Gv1ir ............. -ꜩ0.00092
fees(tz1Ke2h7sDdakHJQh8WX4Z372du1KChsksyU,204) ... +ꜩ0.00092
Transaction:
Amount: ꜩ0
From: tz1RwoEdg4efDQHarsw6aKtMUYvg278Gv1ir
To: KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm
Entrypoint: admin
Parameter: { NIL operation ;
PUSH address "tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm" ;
CONTRACT unit ;
IF_NONE
{ PUSH string "not receiver" ; FAILWITH }
{ PUSH mutez 3 ; UNIT ; TRANSFER_TOKENS ; CONS ; PAIR } }
This transaction was successfully applied
Updated storage:
(Pair 0x0000452d024b72d5897f14a02dc1a3b8e012c802cc3d 2)
Storage size: 251 bytes
Consumed gas: 3987.383
Internal operations:
Transaction:
Amount: ꜩ0.000003
From: KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm
To: tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm
This transaction was successfully applied
Consumed gas: 1427
Balance updates:
KT18rqmG2eV33cZYQR9JMDAtzf8yEp59Nnqm ... -ꜩ0.000003
tz1bDCu64RmcpWahdn9bWrDMi6cu7mXZynHm ... +ꜩ0.000003
```