How to Code Solana Programs in Python: Full Guide.

Okay, so the biggest screw up I see with folks wanting to code Solana programs in Python? They spend weeks grinding Rust tutorials, convinced it's the only path. Nah. You can write full onchain programs - yeah, those smart contracts that live on Solana - using Python syntax thanks to Seahorse. It's this framework that compiles your Python like code to Rust under the hood. In my experience, if you're comfy with Python, you'll ship your first program way faster this way. Why wrestle with borrow checkers when you don't have to?

But here's the thing. Seahorse shines for onchain logic. If you're just querying balances or building offchain stuff, solana py or Moralis APIs got you. We'll hit both. Sound familiar? You've probably dabbled in Ethereum with Web3.py - this is similar, but Solana's stupid fast, like 50k TPS, and fees are ~0.000005 SOL per tx. Basically free.

Grab Your Tools - Local Setup First

Look, jumping into an online playground is tempting, but for real work, set up local. I usually start here 'cause debugging's easier and you control everything.

1. Install Rust: curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh. Restart terminal after.
2. Solana CLI: sh -c "$(curl -sSfL https://release.solana.com/v1.18.11/install)". Check with solana --version.
3. Node.js (v16+): Grab from nodejs.org if you don't have it.
4. Anchor: cargo install --git https://github.com/coral xyz/anchor anchor cli --locked.
5. Now Seahorse: pip install seahorse lang. Or if you're on Mac/Linux, might need brew install python@3.11 first for the right version.

Potential issue? PATH not updating. Log out and back in, or source ~/.bashrc. Test: seahorse --version. Boom.

Your First Seahorse Program: FizzBuzz Onchain

Alright, let's code something. Create a project:

seahorse new fizzbuzz_project
cd fizzbuzz_project

Inside programs/fizzbuzz_project/src/lib.seahorse, you'll see a starter. Edit it like this - classic FizzBuzz that stores state onchain.

python from seahorse import Account, instruction class FizzBuzz(Account): fizz: bool buzz: bool n: int @instruction def init(owner: Account, fizzbuzz: Account[FizzBuzz]): fizzbuzz.init( payer=owner, seeds=['fizzbuzz', owner] ) @instruction def do_fizzbuzz(fizzbuzz: Account[FizzBuzz], n: int): fizzbuzz.fizz = (n % 3) == 0 fizzbuzz.buzz = (n % 5) == 0 if not fizzbuzz.fizz and not fizzbuzz.buzz: fizzbuzz.n = n else: fizzbuzz.n = 0

What's happening? FizzBuzz is your PDA account holding state. init creates it, payer foots the ~0.002 SOL rent exempt bill. do_fizzbuzz crunches the number, sets flags. Simple, right?

Build: anchor build. Deploys to local validator later. But first..

Run Local Validator & Test It

1. solana test validator in one terminal. Grabs devnet feel locally.
2. New terminal: anchor test. Writes tests automatically - check tests/fizzbuzz_project.ts.
3. Airdrop test SOL: solana airdrop 2.

Watch it pass. Boom, your Python program's running on a Solana VM. Fees? Negligible locally. Deploy to devnet: solana config set --url devnet then anchor deploy. Program ID spits out - save it.

Stuck? Validator eats too much RAM? Kill other apps or use solders.litesvm for lighter tests. pip install solders, then it's blazing.

Offchain Python: Querying & Interacting Without Seahorse

• Most time? You're offchain. Building bots, dashboards, backends.
• solana py for RPC calls. Moralis for easy APIs. AnchorPy for calling Seahorse/Rust programs.

pip install solana solders. Basic client:

python from solana.rpc.api import Client client = Client("https://api.devnet.solana.com") balance = client.get_balance("YourWalletPubkeyHere") print(f"Balance: {balance.value / 1000000_000} SOL") # Lamports to SOL

Why devnet? Mainnet's real money. Devnet faucets give free SOL. Mistake here? Forgetting network - always match client URL to your wallet config.

Real Talk: Calling Your Program from Python

Deployed fizzbuzz? Interact with AnchorPy. pip install anchorpy. Grab your program's IDL from target/idl.

from anchorpy import Program, Provider, Wallet
from solana.rpc.async_api import AsyncClient
import asyncio async def main(): client = AsyncClient("https://api.devnet.solana.com") keypair = Wallet.fromsecretkey(..) # Your wallet bytes provider = Provider(client, keypair) prog = Program(idl=youridl, programid="YourProgramId", provider=provider) # Init tx = await prog.rpc["init"]() print("Init tx:", tx) # Call fizzbuzz tx = await prog.rpc["do_fizzbuzz"](15) print("Fizz result tx:", tx)
asyncio.run(main())

In my experience, async is - Solana's async by nature. Sync version exists but slower. Error? "Invalid account"? Check seeds match. PDA derivation's picky.

APIs That Make Life Easy - Moralis Style

Sometimes you don't need full RPC. Moralis Solana Python API? Dead simple for balances, NFTs.

1. Sign up moralis.io, grab API.
2. pip install moralis python dotenv flask flask cors
3. .env: MORALISAPIKEY=yourkey

Quick backend:

python from flask import Flask, request from flask_cors import CORS from moralis import sol_api from dotenv import dotenv_values app = Flask(name) CORS(app) config = dotenv_values(".env") solapi. = config["MORALISAPI_KEY"] @app.route("/balance", methods=["POST"]) def getbalance(): body = request.json res = solapi.account.balance( address=body["address"], network=body["network"] ) return res if name == "main": app.run(port=9000)

Test with curl or frontend. Gets token balances, NFTs. Fees? API's free tier rocks for starters. Limits? Upgrade if hammering.

Common Screw Ups & Fixes

Problem	Why?	Fix
Build fails: "No such instruction"	Seahorse syntax off	Check docs.seahorse lang.com - seeds must match exactly
Tx fails: Insufficient funds	Forgot airdrop	solana airdrop 2 devnet
Local vali crashes	Port 8899 busy	solana test validator --reset
AnchorPy "No IDL"	Didn't build/deploy	anchor build then load idl.json

Honesty time - Solana's account model trips everyone. PDAs over EOAs. Learn seeds early.

Level Up: SPL Tokens & Real Transfers

Want tokens? In Seahorse:

python from spl.token.instructions import initialize_mint @instruction def createtoken(owner: Account, mint: Empty[Mint]): initializemint( decimals=9, mint_authority=owner.(), mint=mint )

Offchain, solana py handles SPL:

python from spl.token.client import Token from solana.keypair import Keypair token = Token(client, mintpubkey, programid, owner) tx = token.transfer(frompubkey, topubkey, owner, amount)

Fees ~0.000005 SOL + rent for new accounts (~0.002 SOL). Track with client.getrecentblockhash().

Playground for Quick Wins

No local? beta.solpg.io. Pick Seahorse crate. Playground wallet auto generates. solana airdrop 2 in terminal. Edit lib.seahorse, Build, Deploy, Test. Done in 5 mins. But for prod, local only.

Next? Bots, Dashboards, Full DApps

Build a trading bot? Subscribe to logs:

python await client.logs_subscribe("program:YourId")

Or dashboards with Streamlit + solana py. In my experience, combine Seahorse for onchain, Python for everything else. You'll crank out prototypes in hours. What's your first project? Hit me up if stuck.