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UPGRADE.md

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+# Upgrading Quasar to v3
+
+This guide provides instructions for upgrading to specific versions of Quasar.
+
+## [v0.3.x](https://github.com/quasar-finance/quasar/releases/tag/v3.0.0)
+
+### `Binary Name Change`
+- This version contains binary name change from `quasarnoded` to `quasard` which requires changes in Cosmovisor settings.
+
+### `Feemarket Module Addition and Relayer Config Changes`
+
+- It contains Feemarket module addition with min gas fee.
+This needs changes on relayer `gas-prices` to be set equal to params set in feemarket module.
+
+- Feemarket brings in variable gas depending on past few block usage which in turn will affect the `gas-adjustment` parameter as well. 
+It should ideally be set to 2 or above.
+
+### Packages
+
+New modules added :
+- PFM v8
+- Ibc-hooks v8
+- Rate-limiting v8
+- Feemarket v1
+
+Updates : 
+- Wasmd v0.45 to v0.51
+- Wasmvm from v1 to v2
+- Cosmos-SDK from v47.12 to v50.9
+- Ibc-go v7 to ibc-go v8
+- Contains updates of Async ICQ, wasm light clients and capability module.
+
+Upgrade removes old unused modules : 
+- `qVesting`
+- `qOracle`
+- `qTransfer`
+