Hello @miriam35, great job on your project. I've gone ahead and looked through your codebase and found a few issues:

Fixes and Improvements

1. Added comments to explain what the checks are used for to improve clarity
2. When trying to change the location or the number of cars available, the wrong index was used for Txn.application_args.
3. I've also noticed that when creating an application or assigning a new value for cars available, the argument wasn't converted to the respective data type(this was causing the create function to fail on the frontend)
4. Added checks when buying a car to make sure that sender is not the creator/owner of the application as this would lead to misleading state changes and also made sure that the order could be fulfilled by the current stock of a car
5. Added checks for the new values of available and location when trying to change them to make sure the value entered wouldn't be empty values(you could let the car's owner put the value of available to Zero)

Good luck and have a nice week ahead!

Hello @JeffCole, great job on your project. I've gone ahead and looked through your smart contract and made a few changes/fixes:

Fixes

1. Improved documentation of code by adding comments to explain what the essential parts of your code base do
2. Added checks for the input data when creating a flower art to prevent unexpected behaviors and issues on the frontend
3. Added checks when buying a flower art to make sure that the sender is not the flower art owner as this could result in a misleading state update of the quantity variable and also that there was enough quantity/stock for the art to fulfill the order
4. Added a check when editing the quantity of a flower art to make sure that only the art's owner can do that.

Good luck and have a nice rest of your week!

Hello @nunu, great job on finishing the course and challenge. I've gone ahead and looked through your codebase and made a few changes:

Improvements

1. Fixed the issue of users being able like and dislike as many times as they wished which could be misused in different ways (for e.g the owner could spam the like function to increase the likes count again and again)
2. Removed the variable dislikes as it could lead to potential issues/over complexity in code to prevent unexpected behaviors/bugs
3. Created the optIn function on the frontend since the new contract changes requires a user to opt into the application to be able to like/dislike(as local storage is being used)
4. Added additional comments to help in documentation

My only suggestions would be to make the respective UI changes and use conditional rendering for the like/dislike functions.

Hello @Arome8240, great job on finishing the course. I've gone ahead and looked through your smart contract and made the following changes/fixes:

Fixes and Improvements

1. Improved documentation of code by adding additional comments
2. Added checks for input data when creating a new gift card application to prevent unexpected issues/behaviors
3. Added checks when buying a card to make sure that the current seller/owner of a gift card is not the one buying his gift card. Furthermore, I've added a check to make sure that the new value for the owner variable is not empty
4. Added checks when selling a card to make sure that the sender is the current owner of the gift card as previously the value sent in application_args could easily be retrieved and misused
5. I'd highly suggest you make the number variable hidden as currently there is no need to buy a gift card as anyone can view the number. Additionally, I'd suggest you add a claim function that would let users only view the number/code of the gift card after buying and claiming the card.

Good luck and have a nice week ahead!

Hello @josefsid, great job on your project. I've gone ahead and looked through your smart contract and made a few changes:

Improvements and Fixes

1. Improved documentation of code by adding additional comments to explain what the functions/subroutines do and what the assert conditions are for
2. Added additional checks for the input data to prevent empty arguments from the input data as they could lead to unexpected behaviors and issues on the front end
3. Removed the owner variable as its purpose could be replaced by the creator_address() available in the Global object
4. Added a check to make sure that the sender when donating is not the creator/owner of the campaign as this would lead to misleading changes to the amountDonated variable
5. Added checks for the isReceiving variable when pausing or resuming a campaign to make sure that the value of the variable met the necessary condition to undergo the necessary change

Good luck and have a nice week ahead!

Hello @Codename, great job on your project! I've gone ahead and tested your dapp and didn't find any bugs/issues. I've also gone ahead and made a few changes/improvements:

Fixes and Improvements

1. Added additional comments in the smart contract to improve documentation of code
2. Added additional checks when creating a new Item application for the input data to prevent unexpected bugs/behaviors on the frontend
3. Added a check when buying an item to make sure that the sender is not the current item owner. Lastly, added a check for the new location value to not be an empty value.

Overall, clean and cool implementation of your project. Good luck and have a nice week ahead!

Hello @IbukunoluwaNap, can you please add your smart contract to help us evaluate your project?

Hello @richiemike, great job on your project. I've gone ahead and looked through your codebase and made a few changes/improvements:

Fixes and Improvements

1. Improved documentation by adding additional comments and fixing typos
2. Added the local variable sharedOpinion to make sure that each user can either review a memory as helpful or not helpful only once as previously users could spam these functions to create misleading updates to the application's state
3. I've noticed that you used Txn.application_args[2] instead of Txn.application_args[1] when calling the editmemory subroutine/function. I've gone ahead and fixed that
4. Removed the redundant checks and added a check for the new description when calling editmemory

Good luck and have a nice week ahead!

Hey @evxinvs, your smart contract file is currently missing.

Hello @Samm_47, here are the changes I've made:

Fixes

1. a Fixed issue that was preventing the smart contract from compiling
2. Added additional checks for the input data when creating the application to prevent unexpected bugs and issues on the frontend
3. Removed unnecessary checks for Txn. note() except when creating the application as everywhere else it was unnecessary
4. Added security checks when archiving and unarchiving a gadget to make sure that only the app owner/creator can do that. I've also added checks to make sure that the archived status was in the right state when toggling to prevent unexpected issues
5. I've noticed that when buying gadgets, the amount in the payment wasn't checked. I've gone ahead and fixed that and also added a check to make sure that the sender is not the app's owner as this would lead to misleading state changes
6. I'd suggest you fix your website since it's currently working.

Good luck and have a nice rest of your week!

Fixes and Improvements

1. Improved the documentation of code by adding relevant comments to describe key parts of the code
2. Implemented input validation when adding a product to ensure that the input data doesn't consist of invalid values such as empty strings that may cause the front-end to have display issues.
3. I've implemented a check in the buy function to ensure that the buyer isn't the creator as this would lead to misleading state changes for the sold value.

Hey princeibs, cool idea and implementation. I've gone ahead and looked through your smart contract and made a few changes:

Improvements

1. Typo fix where you used "125" instead of "127"
2. Implemented validation checks for the input data when creating an application to make sure that the smart contract follows the same validation rules set on the front end
3. Added comments describing the validation checks
4. Added a check to make sure that at least a coffee is sent when calling the buyCoffee function
5. Added a check to make sure that the amount sent in the payment transaction is equal to the amount of coffee the user wants to buy

Overall great job and have a nice weekend ahead!

Hello @kingokonn, great job on your project. I've gone ahead and looked through your smart contract and made two bug fixes and a few other changes:

Fixes and Improvements

1. Users could buy properties that were not for sale which leads to a major security risk
2. Users could like a property more than once; this could lead to misleading updates to the application's state
3. Added comments for what the checks are for
4. Added the function OptIn to run during the OptIn transaction.

Good luck and have a nice week!

Hello @Edobosolomon, great job on your problem. I've gone ahead and looked through your codebase and found a few issues:

Fixes and Improvements

1. There was an issue in compile_contract.py due to the directory chosen for the approve and clear programs which were failing the compiling process
2. There was an issue with calculating the total price on the front end. I've gone ahead and fixed that and also implemented the necessary checks on the smart contract to make sure that the price calculated on the frontend matches the one calculated on the smart contract
3. I'd suggest you remove the marketplace file in the utils directory since you don't seem to use it.

Good luck and have a nice week ahead!

Hello @Server1, good job on finishing the course. I've gone ahead and looked through your smart contract and found a few issues:

Fixes and Improvements

1. Fixed issues and bugs across the smart contract that was leading to issues such as the contract not being able to compile and the functions not acting as intended
2. Buy function wasn't updating the necessary variables and there was a line that was causing an error(the Global.creator_address == Txn.sender() )
3. It is worth noting that Global.creator_address is a method and not a variable. So I've gone ahead and fixed the issue of ownership by adding a variable and making the necessary code changes to reflect the change
4. isForSale was not properly retrieved when calling the toggleSale function
5. I've added checks additional checks when buying a card to make sure that the sender is not the card's owner and that the card is available for sale
6. I've added a line of code to make the isForSale value update to Int(0) when transferring the ownership of a card as the new owner might not expect the card to still be on sale.
7. Added a check for the new owner to make sure that it's a valid address

I'd suggest you deploy a website and update the necessary variables in the constant.js file to reflect the addition of the owner variable(you only need to add one to the globalBytes variable). Good luck and have a nice week ahead!

Hello @Emma360, I've gone ahead and looked through your smart contract and made the following changes:

Fixes and Improvements

1. Modified smart contract to simulate the idea of the project(that is book an event and end booking functionalities)
2. Added new variables to implement those functions but also to implement checks to prevent unexpected issues such as the event's owner ending a booking that has not yet ended
3. Added additional comments to improve the documentation of code
4. Added additional checks to prevent invalid/empty values from the input data and to restrict access to only authorized users

I'd suggest you implement the necessary UI/ front end changes to reflect those changes. Good luck and have a nice week ahead!

Hello @Oliem, great job on your project. I've gone ahead and made some bug fixes/changes:

Fixes and Improvements

1. Improved documentation of code by adding comments describing what the assert conditions are for and what a function does
2. Removed the dislikes variable as it could lead to issues/require adding unnecessary code complexity to fix the issue you had where users could like/dislike a car as many times as they wished
3. Added checks to only allow the current car's owner to sell the car (previously anyone which would be a bug)
4. Added checks to prevent a car's owner to buy his car
5. Added additional checks to prevent empty variables from the input data when creating a new application
6. Added the optIn function on the frontend (you only need to call it on the like function on the frontend)

Good luck and have a nice week ahead!

Hello @agtmaurice, great job on finishing the course. I've gone ahead and looked through your project and found a few issues:

Fixes and Improvements

1. Typo fixes
2. Fixed the issue of schema which was preventing the creation of a new application
3. Fixed the issue of retrieving pictures
4. Added the buy functionality on the smart contract (it was missing)
5. Added checks when liking a picture to make sure each user is able to like only once
6. Added the option state changes to the smart contract
7. Fixed the issue of every user except the application's owner/creator to resume/pause the sale of pictures. This seems to be a bug and could lead to issues
8. You also had issues with your checks for the application_args length. It is worth noting that calling functions created/implemented on the smart contract, means that application_args[0] will be reserved for the keyword required to call a function

I'd suggest you implement the new functionalities on the frontend and fix the current ones as some of your functions seem to throw errors. Good luck and have a nice week ahead!

Hello @anthony, good job on finishing the course. I've gone ahead and looked through your code and found 2 bugs/1 minor improvement:

Fixes and Improvements

1. Added additional checks when creating an animal to prevent empty values from being parsed in (encoded empty strings will still have the length of zero) to prevent unexpected bugs and behaviors on the frontend
2. Added additional checks when adopting an animal to make sure that the new value to be assigned to the OWNER variable is not an empty string and that the sender is not the current owner of the animal
3. Added checks when releasing an animal to make sure that the owner of the current animal is the sender and can be the only one to release it as the value in application_args to compare owner with could be found easily
4. Improved documentation of code by describing what the checks are doing

Good luck and have a nice weekend ahead.

Hello @Maachi, good job on finishing the course. I've gone ahead and looked through your smart contract and made a few changes/fixes:

Fixes and Improvements

1. Improved documentation of code by adding additional comments detailing the complex part of the smart contracts
2. Added more checks for input data when creating a new application to prevent unexpected behaviors/issues
3. Added checks when buying a product to make sure that sender is not the product's owner as this could lead to unexpected behaviors where the quantity amount would be decreased which could be misleading. Furthermore, I've added new checks to make sure that the quantity sent is valid and that there are enough products in stock to fulfill the order
4. Added checks for quantity and made sure that the sender that is calling the edit function/subroutine is the product's owner as this was previously a bug where everyone could modify the quantity amount

Good luck and have a nice week ahead!

Hello @maryjobs, great job on your project. I've looked through your files and made a few fixes:

Fixes and Improvements

1. Added checks for the new values for description and image when calling the respective function to update them to prevent unexpected behaviors and issues
2. I've noticed that watches could be bought by anyone at any time, so I've gone ahead and fixed this issue by adding a boolean Sale.
3. I've also added a function to toggle the sale value
4. Removed redundant variables and checks
5. Fixed schema issues that were preventing the creation of new applications

Good luck and have a nice week!

Hello @francess, cool idea and implementation. I've gone ahead and looked through your smart contract files and made a few changes:

Fixes and Improvements

1. There was an issue when storing the count for each meal where if a previous meal was already initialized with a count, the same meal would have the previously stored count overridden instead of being added to the new count
2. Removed the marketplace place smart contract files as you didn't need them
3. Added additional checks for the input data when creating a meal to make sure that there were no empty/invalid values
4. Added a check to make sure that only the payment address can create new meals as anyone being able to create meals for a restaurant could lead to potential issues.

Overall, great job and have a nice weekend ahead!

Hello @Kishore, great job on your project. I've tested your dapp and looked through your codebase and made a few improvements:

Improvements

1. Removed the average rating variable as it was leading to unnecessary gas costs since the value had to be reassigned and updated every time a new rating was added. This variable is unnecessary since it's something that can easily be calculated using the respective variables from which it was being derived.
2. Added a check for hours to make sure that it was valid since the function could be abused to lead to misleading changes to the state of the number of buyers for the application by only paying for the gas fees
3. Added two checks when supporting a mentor to make sure that the mentor is not the sender as this could lead to misleading changes and also to make sure that the amount specified matches the amount sent in the payment transaction.

Overall great job and sleek UI. Good luck and have a nice rest of your week!

Hello @Tevin, great job on your project. I've gone ahead and looked through your smart contract and made a few changes/fixes:

Fixes and Improvements

1. Cleanup of redundant variables that were not used/already provided by another variable (the creator address in the Global object/class)
2. I've noticed that users could like and dislikes as many times as they wished. I've gone ahead and fixed that by having a local variable like keep track of whether the sender has liked it. I didn't add a check in the like and dislike subroutine/function to check if the user has opted in since it's already required by the blockchain to be able to use local storage, however, feel to add one if you see the need for it.
3. Implemented the function to run when a user opts in.
4. Added additional comments for clarify of what the checks are doing

Good luck and have a nice weekend ahead!

Hey @Patra, great job on your Dapp. Here are the changes I've made after testing your Dapp:

Fixes and Improvements

1. There was an issue where a product's owner could make the discount amount to be greater than the selling price which would break the buy functionality. I've gone ahead and implemented checks for that on the frontend when creating a product and also when updating the discount amount
2. Improved clarity discount input field as it could be confused as a percentage when in this case, it's an amount in ALGOs
3. Removed the creator variable in the smart contract as it wasn't used for anything and Global.creator_address() could be used for its current use cases.
4. Added additional checks when creating a new product to make sure that the input data does not contain invalid or empty data as this could lead to unexpected behaviors on the frontend.
5. Removed the check for the new value of the stock when calling update_stock to allow flexibility for a user to put the stock at zero which could be used to show that product is out of stock.

Good luck and have a nice rest of your week!