---
title: "Troubleshoot SVM Price Feeds: Fix Anchor-Lang Version Mismatch"
description: >-
  Step-by-step guide to align anchor-lang versions in Cargo.toml and Cargo.lock
  to resolve Pyth SVM compilation errors affecting Solana price feeds.
full: false
index: false
---

# Troubleshoot Solana Price Feeds Contract

This reference page is designed to help you troubleshoot common issues you may encounter when using Pyth Price Feeds on SVM chains.
Follow the steps provided below to diagnose and resolve the issue.

1. `error[E0277]: the trait bound PriceUpdateV2: anchor_lang::AccountDeserialize is not satisfied{:rust}`

   This error happens when a program using the [`pyth-solana-receiver-sdk`](https://github.com/pyth-network/pyth-crosschain/tree/main/target_chains/solana/pyth_solana_receiver_sdk) fails to compile. It is caused by an `anchor-lang` version mismatch.
   Make sure the transitive version of `anchor-lang` brought by `pyth-solana-receiver-sdk`
   matches the version of `anchor-lang` of your program's `Cargo.toml`.

   You can fix it by following these steps:

   - Check the version of `anchor-lang` in your [`Cargo.toml`](https://github.com/guibescos/anchor-pyth/blob/broken-build/programs/anchor-pyth/Cargo.toml) (in the example `0.29.0{:js}`) call it `x.y.z`
   - Check the version of `anchor-lang` in the `pyth-solana-receiver-sdk` tree in [`Cargo.lock`](https://github.com/guibescos/anchor-pyth/blob/broken-build/Cargo.lock#L1400) (in the example `0.30.1{:js}`) call it `a.b.c`
   - Run `cargo update -p anchor-lang@a.b.c --precise x.y.z{:bash}`
     replacing `a.b.c` and `x.y.z` by the versions in the previous steps. For example:\
     `cargo update -p anchor-lang@0.30.1 --precise 0.29.0{:bash}`
