Find Freelance Solidity Jobs

Check out 36 posted Solidity Jobs. At LaborX you have a great option to choose a freelance job for Solidity Apply for a job now and get paid in cryptocurrency.
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Dapp update with bug fix and completion

We are new company which want to make our own cryto project as first ranking in the crypto world.
We will launch our own appasap but it still has got some bugs and also needs to add more features for completion.
Our old developer has got problems now and so we need more developers who are really good at smart contract/web3 UI.
If you are good at above skills, please reply. We will share with you all informations about our projects and we can deal other more important things.
We will share current projects with you and will hire with highly rate.
Remember that we will hire only talent and experts.

Trading Bot

Your primary focus will be to identify and capture profitable arbitrage opportunity by monitoring blockchain transactions and executing trades in real-time

Fork indexer and onepage frontend using react, tailwind

In direct. Using react, ethers, axios, tailwind, wagmi ( and rainbowkit (

Building a Custodial crypto wallet

We are building a non custodial crypto wallet using account abstraction. Since AA allows for transaction batching we are also building a complementary marketplace for devs to deploy their strategies (1click automations) so that a user doesnt have to leave the wallet. Example Yearn Strategies and Donkey finance.
In addition to the marketplace web app, there will be a GitHub repository containing a base strategy with hooks (like the hooks _beforeTransfer, _afterTransfer), allowing developers to create their own customized flows.
1 cent base fee on all transactions + 20% murkup on gas. this fee is split 50/50 with the deployer of the automation.
You will be building a number of base defi automations (batched transactions) + design and develop an onchain strategy factory for strategy deployment. Creation of all the necessary documentation for other developers will have to be worked on in parallel (wrappers, building blocks for strategy creation, helpers, protocol integration handlers, token handling)
Once you grasp the idea i would like to hear what would be your approach to designing and developing the onchain strategy factory.
So please write a proposal with your detailed approach. 
I will continue discussion with well written proposal candidate.

create an nft mining website

i need a developer who can help me with my project send me your offers and i will get back to for moreinfo about my project!!!

Create a Beefy fork

I need a dev web3 front end developer to create a beefy fork. Work will be to add new network on the fork and implement the pool.

Smart Contract Update (Solidity)

The budget for this is $180. If it is not acceptable to you,do not proceed further.
I want to make changes to the attached experimental smart contract I am creating.
Here are my proposed updates:
When depositors decide to buy or sell RightsToken, the smart contract will implement an arbitrage to profit from the difference in prices. It will then use 66.666% of the profits to buy RightsToken.
Let the Yearly Average Value Calculation reset to zero after 365.25 days or 8766 hours.
Protecting the Token Price from Manipulation
To protect the token price from manipulation, we can implement dynamic fee and price impact restrictions for the RightsToken. This can be done by following these steps:
1. Implement a function in the smart contract that calculates the transaction fee based on the transaction size and slippage. The formula for calculating the fee is:
fee = (transaction size * slippage * dailyAverageFee) / 100
Here, transaction size represents the value of the transaction, slippage is the calculated slippage, and dailyAverageFee is the daily average fee of 0.00925925925925926%.
2. Implement a check in the smart contract to ensure that the transaction's impact on the token price remains within the desired limits. The maximum allowed price impact can be calculated using the formula:
maxPriceImpact = token supply * dailyPriceChangeLimit
Here, tokenSupply is the current supply of RightsToken, and dailyPriceChangeLimit is the desired limit of 0.00253504702% (daily).
3. Before executing a transaction, validate the fee and price impact. Compare the calculated fee against a minimum fee threshold to ensure it is economically viable. Also, compare the calculated price impact against the maximum allowed price impact. If either of these conditions is not met, revert the transaction and provide an appropriate error message.
4. The 33.333% of the fees will be distributed among token holders in proportion to their token deposits. Implement a function to calculate and distribute the fees periodically.
5. Include a mechanism that would reward long-term depositors and reset reward parameters when deposits are accessed.
6. Provide an option for users who want the smart contract to help them to buy or sell at the minimum fee.

Create a web platform for voting with blockchain recording

Creation of a web platform for managing online elections with blockchain recording.
Service presentation frontend with explanation pages and graphics.
Area reserved for voting.
Reserved area for administrators with candidacy management.
Attributes and features for users:
• When called, they have the opportunity to vote for a candidate
• Insertion of candidates with dedicated page
• Timing management of opening and closing elections
Logics and implementations on blockchain (Ethereum or Polygon):
During registration, each user must be linked to a crypto wallet address
You will need to create a smart contract in Solidity to manage entitlements and interactions with voter wallets and record recording for candidates.
You will have to use a web3 library to make the platform interact with the smart contract.
Operation of voting and interaction with blockchain:
1. Administrators open voting
2. Voting wallets are enabled through interaction with the smart contract
3. By interacting with the wallet, the user casts his vote and it is not possible to vote a second time.
4. When the directors close the voting it is no longer possible to vote

Smart Contract Program for Ethereum BlockChain

Need a smart contract that pays reflections on the ethereum blockchain. This contract doesn't need written from scratch. You can use an MIT open source contract and add code to it. I'll run the solidity compiler and deploy the contract myself when its ready at From you I need the smart contract ready to compile & deploy.
Smart Contract Requirements:
1) total supply 100,000,000
2) buy tax for all transactions 3%.
3) sell tax for all transactions 3%.
4) 2% of buy & sell tax is distributed to holders.
5) 1% of buy & sell tax is sent to devs wallet.
6) reflections paid in eth.
7) user must hold minimum 1,000 coins to receive eth reflection.
8) eth reflections are paid based on the % of coins in holders wallet. (more coins held larger the reward)
You can decide what threshold eth distribution happens. The contract must pass audit checks from these websites:
Code must pass audit. 

ERC721,1155 Smart contract developer is needed

We need a smart contract developer to develop a contract
- Contract should be Upgradeable
- Allows multiple NFT's (ERC1155) to be locked against another NFT (ERC721).
- When locking the ERC1155 it should have a vesting period (that can be set)
- When it's gone past the vesting period who ever owns the NFT (ERC721) is allowed to claim that 1155 token and have it come back to their wallet.
- Contract should support as well (for the owner of the ERC721) 
We need to develop a engineer urgently.

Blockchain Developer

need blockchain engineer who can work with me for several months.
you can receive the payment after finish work.
because I am a developer as well.

Tech Lead Frontend

Looking for Tech Lead Frontend (React + web3) to work on projects such as DEX, Bridge 
About us:
Hawex Group Ltd is a fintech company based in the UK. We are building a dynamically developing ecosystem of financial and blockchain products. We are free from bureaucracy and separate business from the tedious routine.
We specialize in mobile banking and wallets, consulting of fintech and blockchain projects, CeFI and DeFi payment solutions, creating smart contracts, exchange and p2p solutions, etc.
What we expect:
— Experience with web3 projects
— Understanding the essence of system analysis
— The ability to explain the architecture of the project in the language of non—technical specialists and consistently describe the operation of the application at the code level
— Strong knowledge of ReactJS, TypeScript
— Ability to understand legacy code
— Development, maintenance, optimization of architecture and technical documentation of products
— Conducting Code Review
— Team management during the development of the front part of blockchain projects: DEX, Bridge, Collateral tokens, DAO
— Break down complex technical tasks into simple steps
— Understand other developers' code, make refactoring decisions and justify them
— Solve complex technical problems independently
— Confident knowledge of the Russian language 
What we offer:
— Remote work format 
— 36 paid days off per year
— Corporate training — courses, trainings, meetups and conferences
— Developed corporate culture — we go in for sports together, skydive, arrange the best corporate parties, sort waste for recycling, read books, watch good movies, solve complex problems and strive to make this world a better place
— A team of experienced, motivated, passionate colleagues
— Career growth — the team is constantly growing. Depending on the contribution, each employee can qualify for an increase in income, new functionality and additional tasks. We take care of our employees
— Cool web3 projects with clients all over the world