I've taken the liberty of rounding up all the questions and answers provided from Hydro's most recent AMA hosted with BitcoinMarkets incase you missed it. Enjoy! Hydro Q&A’s Q (knonsu):
How does Snowflake relate to other identity protocols out there like Civic and uPort ? A.1 (Anurag):
We see snowflake as existing a layer below these types of projects. Even without blockchain, identity is a broad term. Different people around the world have different forms of identity (state ID, country ID, social media IDs, etc). Civic, uPort, and other blockchain projects help to build specific types of an on-chain identity for a user; however those IDs are meaningful in different ways to different observers. For instance, imagine that a government or business builds a system that accepts Civic as a form of identity while another government/business only recognizes uPort identities. On top of this, certain systems only care about information tied to a user’s social media profile. A user can maintain one standard Snowflake as a base layer and set each of these different forms of identity as a resolver. Snowflake eliminates the need for global unanimous adoption of a singular identity standard and rather allows systems to build business logic off of identity standards they themselves recognize. Follow up Q (knonsu):
thats cool. so its totally depends on the person/ institute utilizing it . One problem I found is how easy its to create fake identities (in their basic system). A.2 (Anurag):
Yup! So people can conduct off-chain verifications to prove that you own a snowflake, and then tie an on-chain verification to your Snowflake. This links real-world KYC to your on-chain ID, so sure you could mint another snowflake, but that same party won't validate it again for you. Anyone who trusts that party would be able to accept their validations, and people who don't trust that party can rely on a different validator they do trust.
— Q (kat):
How big is the team working specifically on Hydro products? Can we get a numbers breakdown of engineers, biz dev, etc? Do you have plans to scale this team as the Hydro project develops? A.1 (Andy):
Our Hydro team is 8 people.
Devlopers (Myself and Noah)
Product (Anurag and Shane)
Founders (Mike and Matt)
The nice thing about Hydrogen though is we have a team of 30 people who we can leverage for different things. For example, Noah and I do not build mobile apps, but we have a front end team that is well versed in mobile app development. So while they are not directly on the Hydro team they do have a direct impact on Hydro.
Hydrogen as a company is working to grow pretty rapidly. As we grow we will be filling out more positions in both blockchain and non-blockchain rolls. A.2 (Anurag):
To add to Andy's answer - pretty much everyone working for Hydrogen helps out with Hydro in some way, whether via design, front-end development, API support, business discussion, etc.
Here's our full team: https://www.hydrogenplatform.com/about
— Q (rocket man):
So in the age of ICOs, what motivated your team to not pursue that funding model and instead have a token distribution for developers? A (Andy):
This was something that we spent a very long time considering and discussing. We spent a lot of resources (time, money & energy) trying to find the best solution for us going forward. When it was all said and done, we decided on an airdrop because of two main things, getting the token into the hands of people who will actually use it and regulatory concerns.
We feel as though our distribution was the fairest approach that allowed for people with actual interest in the Hydro community to get involved. Overall, we have been very pleased with the level of community engagement from people who are interested in the utility of the Hydro token and we feel that a lot of this can be credited to our distribution strategy.
— Q (matheussiq8):
How hydro tokens will be used is still vague in the Snowflake whitepaper draft. Would the amount required to hold depend on the volume of API calls or some other parameter? For example, if I decide to implement raindrop and later snowflake in my small webshop would I need to hold the same amount of tokens as Binance (if they ever implement it of course…)? A (Noah):
as always, the permissionlessness of public blockchains is a double-edged sword. smart contracts partially solve the problem by letting us enforce certain things on-chain (minimum token balances, signature validity, etc.), but there are limits. so, re. your specific question: in raindrop we do not vary the staking requirement across users, because that would necessarily involve value judgements we are not comfortable making as a centralized entity. however, there are two types of staking required for raindrop:
- “institutional staking” requires entities who wish to sign up raindrop users *on their behalf* (i.e. passing new users’ addresses to the smart contract as parameters rather than new users transacting directly from their accounts) to stake a significant amount of hydro. these are the players we want to ensure are acting in the best interests of the community. in this model, hydro is simply one of many institutional stakers (where we sign up users on our kickass mobile app, which will be out soon).
- “user staking” requires individuals who wish to sign up for raindrop on their own, i.e. transact directly with the smart contract, are able to do so by staking a much smaller amount of hydro.
What this all means for you, as a potential customer of our API, is that you don’t actually have to worry about the staking requirement or signing up users at all, and can simply use our API in conjunction with the Hydro app.
Looking ahead to Snowflake, we have big plans to integrate increasing sophisticated uses of the token into the product. to some extent these are still up in the air, but rest assured that we are very focused on building a strong tokenomics structure. At a high level, the core token mechanism for snowflake will involve depositing tokens into the snowflake smart contract. These deposits will allow native staking/payment/incentive functionality denominated in hydro, without the hassle and worry of using ether with every call.
— Q (Hodlall):
When is raindrop Android app is releasing A (Andy):
It is currently under development. We have a bunch of android phones with different OS on the way. It is hard to give a set date as we don't know what unforeseen issues could come up during the process though. All I can say is it is literally all that our mobile development team is working on
— Q (Jeff_We_Cannafi):
To piggyback on matheussiq8’s question, how do these identity tokens compare to existing forms of identity authentication, and do you anticipate the tokens themselves will be traded on exchanges? A (Andy):
In my opinion, the main difference between what we are working towards and others like civic and uport is the scope of what we are aiming to do. We understand the value of having KYC on the blockchain and "One click signup", but really I think blockchain identity can be so much more than that. We are aiming to create a completely extendable and modular protocol which will allow for people to link anything they desire to their blockchain identity. Other protocols can tend to lean towards centralization (more a fault of current KYC procedures than the projects themselves) and we feel like this doesn't have to be the case. At least for now, something like KYC needs to have central authorities to verify user information, but why can't I also link my crypto kitties to my blockchain id or my linkedin profile to my blockchain id?
Overall, what we are trying to build will easily allow for other blockchain developers to create robust identity solutions for whatever application they feel fit with Snowflake being at the core of that. We feel that this is crucial to eventually creating a completely open and decentralized identity system. Anyone can join and anyone can add what THEY consider to be an identity, but I only have to accept what I consider to be an identity.
As far as trading, Snowflake Identity tokens will never be tradable. We feel that you identity should always be linked to you. This would be a dangerous road to a very easy black market for people's identities
— Q (Jrock):
What do you find the hardest part of pitching icos to regular companies?
Also what do you think needs to happen for widespread crypto adoption? A (Shane):
If you mean pitching Hydro to regular companies (we're not an ICO :stuck_out_tongue:), I would say the hardest part is getting the larger companies to move faster than a snail's pace. There are too many chefs in the kitchen and sometimes there is a lack of top-down strategy on blockchain, and it leaves large enterprises paralyzed sometimes. We try to resolve this by pitching how easy Hydro is to use, and how it connects to our broader Hydrogen ecosystem which can add value in a lot of places.
In my opinion, widespread crypto adoption is going to be dependent on how parallelization plays out. If crypto's only option is to create a new parallel economy, widespread adoption is going to be slow and arduous and will take decades. However, if blockchain is able to be infused or layered on some of the current systems we have in place, the adoption will be much faster and broader. Ultimately this comes down to the usage of private vs public chains - the more private and centralized chains that get implemented, the farther the mainstream adoption will get pushed out.
— Q (Luke):
One aspect of Hydro that is beginning to really intrigue me are the potential use cases and dapps that can be built by external developers ontop of the Hydro protocol layers for each phase.
- Having held various dev meetups and networking at various conferences, how are you finding the process of attracting developers to start building dapps and products in your ecosystem?
- I understand the HCDP is getting updated with various new rules and bounties for dapps to be built, have you approached any developers yet with this new offer, and if so, how has the reception been?
- How else do you intend to attract developers towards building on the Hydro protocols?
- Through our events, we're mainly focused on helping expand the blockchain-focused developer community. We help give exposure to projects we find to be doing neat, innovative work in the space and keep ongoing dialogue with these communities.
- In particular, to provide impetus to developers in the Hydro ecosystem, we've established the HCDP. The new process will involve putting out specific task requests. In the next week or so we'll have published specifications for dApps that can be built on top of Snowflake. We ourselves will not be building these dApps (they have nothing to do with Hydrogen's space as a company). This helps the ecosystem expand outside of Hydrogen-specific use-cases.
- ^^Through the above process to get them started. Eventually, we want the Hydro development process to be community-driven, so people are building on Hydro because it benefits their own programs and applications.
— Q (elmer_FUD):
Hey Hydro Team! Here's a few question I've got for you after checking out the Raindrop and Snowflake whitepapers:
How has your experience working in the Ethereum ecosystem been so far?
While you are currently focused on the financial sector, would you consider actively marketing to other sectors such as healthcare and education in the future?
It seems like both Raindrop and Snowflake would be useful in any environment that processes or stores sensitive data.
Do you have plans to release official Raindrop SDK packages in other languages in the future?
A bit more of a specific question: Raindrop is looks like a great product to use in a PCI-DSS environment - do you have thoughts on whether or not it the product is ready for primetime and do you think the industry standards and government regulation is prepared to handle these kinds of systems? A (Andy):
Thanks for the questions! I'm gonna answer each in a separate response in this thread
Overall it has been pretty solid. There is still a ton of room for growth in terms of documentation and stuff like that, but it is miles ahead of basically every other blockchain platform I have worked with. By far the biggest pain has been handling gas costs when considering the user experience. When trying to build actual products that people will want to use we feel that making it user friendly is something that many blockchain projects have not focused on nearly enough.
Yeah certainly. We focus on fintech as that is where the rest of our companies APIs focus and that is where we have the most connections, but much of what we are building is much further reaching than that. Just as far as authentication goes, it really can apply to any major field and we intend to market it as such.
We currently have Python and JS SDKs and have had a few java ones submitted through our community dev program. We have been revamping that program, but I anticipate we will be putting up more bounties for most major languages. I have considered making a few more myself, but we feel that they could be better suited as community projects.
I completely agree. Raindrop and blockchain authentication when handling anything around payments is a great application. I think the biggest thing is actually convincing regulatory bodies that the protocols we have build are secure (since many can still be scared of blockchain). I definitely see this as a direct use case though
— Q.1 (khonsu):
What kind of banking relations do you have as a company, do they (banks) understand what you are trying to do ? Any VCs approached you for funding ? explain your business model. A.1 (Shane):
Hydrogen has existed since 2009 in the form of Hedgeable. Hedgeable is a consumer-facing online investing app, and the tech behind it eventually spawned the Hydrogen tech platform. The story of how the transition happened goes essentially like this: (1) Hedgeable was disrupting banks & investing firms, (2) banks & investing firms started contacting us and seeing if we would help them digitize & automate their own businesses, (3) we started packaging up our tech and selling it to the banks. There was so much demand for this from financial institutions that we spun out a new company (Hydrogen).
So to get back to your original question: we have some long-standing relationships in the banking & finance world, and to this day we have inbound leads from that space coming in every week. The key thing to keep in mind is that these institutions move extremely slowly, but they do understand the core value prop of our platform. Many of these firms are still in the midst of basic digitization efforts (i.e. moving from really slow offline processes to simple digital infrastructure), and that is the primary thing we are helping them with in early stages. But they are also keen on blockchain tech and they will naturally turn to us for that once they reach that point. We do have a few relationships with big financial companies in which Hydro/blockchain are already part of the discussion.
We have revenue and don't need to rely on VCs. It is our general philosophy that building a business sustainably with actual clients and revenue is a good approach, but we would consider working with the right VC if that came to be and we wanted to scale more quickly. Right now, that is not an immediate concern for us.
Our business model is in charging developers and enterprises to access the Hydrogen technology platform, which currently consists of products like Atom, Ion, and Hydro. Developers pay a per-user fee to hit our core APIs, while large enterprises negotiate custom (usually multi-year) contracts with us that typically include recurring revenue. Hydro, specifically, is being offered for free right now, as we attempt to gain adoption. But it is important to note that Hydro is just one piece of our ecosystem. Q.2 (Joleen):
When you say fee - is this fee HYDRO? And when do you envisage HYDRO to no longer be offered FOC? A
**.2 (Shane):** Sorry if it wasn't clear, I meant free to use our Hydro tech/APIs. The usage of HYDRO tokens within that is a separate issue - they still need to have HYDRO and we do not give it away for free to clients
— Q (guacam0le):
Adoption of an identity management solution (etc) would potentially involve a lot of identities. Further, scalability is a hot topic w/ blockchain. Is this a potential bottleneck? What is or might be done to address such?
Tackling a competitor like Google or Authy's 2FA is no small feat. Also, not everyone is yet to embrace blockchain-based solutions. Have you found it difficult to interface with enterprises & get them excited about the idea of an overhaul? A (Anurag):
nowflake is designed to be relatively low-load on the blockchain. A user needs to conduct a single transaction to “mint” their Snowflake. Once this is complete, they would need to complete one-time transactions to set each of their different forms of identities as resolvers as needed. A Snowflake is designed to be built out via resolvers over the duration of a user’s lifetime, so there’s never a need for heavy, frequent transactional capability. Similarly, smart contracts simply need to be set as resolvers by users; they do not themselves transact. Network scalability improvements will increase the range of use-cases for smart contracts that can be tied to Snowflake, but they aren’t a necessary prerequisite to some important early use-cases such as KYC platforms, and a few basic user-interaction platforms.
As far as competition, we feel that current adoption of 2FA is, in general far short of where it should be, and any 2FA is generally better than none. Many businesses use text-message based 2FA, etc. In the short-run we are aiming toward pilot implementations with small businesses. To further this, we have put out many integration resources, guides, and documentation and accordingly believe implementation of Raindrop is a more straightforward workflow. As far as large enterprises go, Hydrogen has clients, so it is helpful for our project to have those connections. Large institutions are generally relatively slow-moving, but have expressed interest in using Raindrop, in particular for securing employee accounts. As the product grows, we may eventually move in this direction with Client Raindrop, but resources will always be available for any site that wants to adopt it. Additionally, we are looking into making a wordpress plug-in to make implementation much more accessible for many developers.
-- Q (Smithymethods):
I know Hydro is a fintech company, hydro plan to curb phishing and hacking to the bearest minimum we know that hacking is very rampant these days on MEW and with other wallet. Is Hydro planning to create a wallet that support hydro and other tokens using their raindrop Technology?
As this will put an end to the problem of phishing and also promote hydro A (Noah):
like everyone in the crypto space, we’re very worried about phishing, both personally and on behalf of all hydro token holders. we first want to reemphasize that preventing scams and fraud has to be a community-driven effort: teams and users need to be vigilant and promote best practices (never trusting links in public chats, shunning fake accounts, etc.). we are excited about raindrop’s potential to help combat phishing, though. we actually talked with someone about mycrypto about integrating raindrop into their desktop app. we’ve forked their code and are researching how feasible an implementation would be, stay tuned for updates!
— Q (Hodlall):
What security measures in place for hydro , I see lot of tokens being hacked nowadays , and money is stolen.. how does hydro make sure their team tokens are completely secured or as much as possible A (Andy):
We all have been in crypto for a while and are pretty well versed in securing our stuff. Our tokens that are currently locked are in cold storage. Others are held in hardware wallets
— Q (Joleen):
We know that the Hydrogen platform is going to be used by CI Investments, a large insurance firm and a world top 20 bank, have these companies already begun purchasing Hydro OTC? A (Andy):
This is something that we feel is best to be hands off with. It is really up to the discretion of our partners
— Q (khonsu’s mumaffi):
Ill be honest i have not yet fully read the whitepaper but id like to know other than investor growth do you truly believe there is interest in a model where users have to pay each time for access? How big do u expect this fee to be...for large companies dont you believe this is an unscalable practice? This may be a question more about most technologies built on token based economics too. A (Andy):
So we have 2 different authentication protocols. One happens less often and is in the same vein as OAuth. This is called Server-Side Raindrop. This requires tokens to be sent. This protocol would only happen once per day for a business when accessing something like an API. I don't feel that these values are extremely high for increased security.
Our second protocol, Client-Side Raindrop, functions much more like google auth. This logic actually does not require any tokens or even a transaction by the end user. It is 100% free for them to use and they will never have to pay for a transaction. Here the responsibility is on the implementing party to stake tokens. This allows them to onboard users and authenticate them.
We felt it was crucial to have an authentication that did not have a cost per user login as it is not scalable
— Q (khonsu’s mumaffi):
Also do u plan to tokenise atom and ion too and if not covered earlier how big of an impact do the market conditions have on your business A (Anurag):
Tough to say we're going to "tokenize" them since that word can carry a lot of different meanings in different contexts, but we do plan on integrating the entire Hydrogen platform with Hydro. This will most likely take the form of enhancements to systems leveraging Hydro. You can find a more detailed breakdown on our Hydro roadmap: https://medium.com/hydrogen-api/project-hydro-features-in-depth-look-39faa29f0d61
Market conditions don't really have an impact - we're still building the same tech on a day-to-day basis
— Q (ghost):
As a company in the space, do you see the fact that tokens have to be acquired on exchanges as an issue? How would a company that wants to develop with you acquire tokens? A (Anurag):
Depends on what they're developing. dApps developing using Hydro smart contracts to create native functionality to their applications would need to acquire those tokens on their own; however, companies using the Hydrogen API will not. Here's a detailed article outlining when a developer would need the token for the Client Raindrop smart contract: https://medium.com/hydrogen-api/how-to-use-client-raindrop-without-using-the-hydrogen-api-bb04934ae293
— Q (jarederaj):
Can you describe your stakeholders and give me a better sense of the exigency of your products? Who are you focused on serving with your platform and why are they motivated to use your platform? A (Shane):
The Hydrogen platform serves developers and enterprises who want to build applications. We are specifically targeting the financial services sector, including banks, investing firms, insurance providers, and financial advisors. This includes large enterprises, individual developers, and startups.
Our products are Atom (core digital infrastructure & engine for finserv), Ion (AutoML & business intelligence capabilities), and Hydro (blockchain & decentralization layer). Each has a different use case but these products combine to form an ecosystem of tools for developers to build sophisticated applications with.
The main pain point we are addressing is the resources required to build, launch, and run a digital financial application. These resources include both time and money.
Large enterprises have resources, but they waste years and millions of dollars trying to launch digital platforms (we've seen this first-hand), often unsuccessfully. The motivation here is obvious. Startups and smaller developers, on the other hand, do not have access to huge resource pools, so they are forced to look for solutions that make the process more efficient.
In the same way that Wordpress makes launching a blog easy and also allows for extended functionality, Hydrogen makes launching fintech application easy.
— Q (shujjishah):
When the app will be released??? A (Anurag):
We're going through our mobile development very iteratively. Since we work very closely with the product, there are things we can't recognize until we've got people beta testing the app. As we started Beta testing and conducting user-research, we realized that one aspect of the UI for the app was not intuitive to about half of our testers. We decided to make a few API changes to enable the mobile app to display a "linked" vs "unlinked" status in order to improve the user experience. Our front-end team is finalizing these changes, so our Beta testers will receive a new build in their testflight apps within the next few days. This new build will require another round of Beta testing to ensure that none of the code changes causes any problems on devices; if this change goes smoothly, and our mainnet testing goes smoothly, we will be able to release the app this month.
Since there isn't much precedent on releasing a product into the app store that connects users with the ethereum mainnet, our primary concern is making sure the product works fully as intended and provides an intuitive user experience. Misc Q&A’s Q (elmer_FUD):
What's your favorite thing to drink? A.1 (Andy):
Overall, I really love Baja Blast Mountain Dew. If I am drinking, I'm a big fan of fruity beers like Blue Moon and Shocktop. Also had a really good raspberry sour recently A.2 (Nahom):
Primary=water but i do enjoy Jamaican ginger ale/beer. We keep honest tea in the office too, i love it because it brings me back from the dead:skull_and_crossbones:, @Hydro Andy drinks most of it behind my back though :triumph: A.3 (Noah):
hard: tequila or picklebacks
soft: any sour beer
other: mango juice
i also crush like 2 nalgene’s worth of water every day at work A.4 (Shane):
For hard alcohol: whiskey/bourbon A.5 (Anurag):
ooh, went to the finback brewery last weekend; was wonderful
— Q (Joleen):
Do you HODL any other tokens personally? A.1 (Andy):
I do. I think it is probably best to not say which, but if you follow me enough in #altcoins I am sure you will see me talk about a few A.2 (Noah):
im a bit of an eth maximalist actually :grimacing: i do dabble though
— Q (Joleen):
Who got who in the World Cup sweepstakes? A.1 (Andy):
I'm going for Germany, but I know next to nothing about soccer A.2 (Shane):
I'm rooting for Portugal, but I don't think they're going to win the cup
— Q (Joleen):
Who's got the best banter in the office? And who has the worst? A.1 (Andy):
One of our backend devs, Paavan, typically has some great banter
and even better hot takes A.2 (Noah):
dont @ me for worst banter A.3 (Shane):
Sabih (BA @ Hydrogen) banter is by far the best
The Litecoin blockchain is capable of handling higher transaction volume than its counterpart - Bitcoin. Due to more frequent block generation, the network supports more transactions without a need to modify the software in the future. As a result, merchants get faster confirmation times, while still having ability to wait for more confirmations when selling bigger ticket items. Wallet ... Monero is a privacy-focused coin which currently sits around the top 10 of Cryptocurrencies by marketcap. Mining Monero can be a profitable venture due to its cryptographic algorithm which is resistant to ASIC’s mining. This means that anyone with a CPU or GPU can mine for Monero. Hive este un portofel pentru OS X cu niște funcții unice, inclusiv o aplicație de magazin care te conectează direct la servicii bitcoin. Unele portofele desktop sunt construite pentru securitate sporită. Armory intră în această categorie. Altele se concentrează pe anonimitate. DarkWallet folosește un plugin ușurel pentru browser pentru a oferi servicii ca amestecarea monedelor ... On hosted Bitcoin wallets such as Coinbase or Bitcoin exchanges like Binance. If that’s your answer, then you should know that you are putting the ownership of your Bitcoins under great risk!! These services keep your Bitcoin private keys under their custody on your behalf, which is not a safe practice, because the only way to claim your Bitcoins is your Bitcoin private key. If you don’t ... Port TCP/8333 is the port generally used to connect with Bitcoin Cash. Hosting a full node using a local machine is just as easy to set up, but it’s good to make sure your computer won’t be ... OS X will open a Finder window for you to drag Bitcoin Core to your Applications folder. Bitcoin Core GUI. The first time running Bitcoin Core, Max OS X will ask you to confirm that you want to run it: You will be prompted to choose a directory to store the Bitcoin block chain and your wallet. Unless you have a separate partition or drive you ... Bitcoin Core initial synchronization will take time and download a lot of data. You should make sure that you have enough bandwidth and storage for the full block chain size (over 350GB). If you have a good Internet connection, you can help strengthen the network by keeping your PC running with Bitcoin Core and port 8333 open. Bitcoin Unlimited (BU) is a fork of the Bitcoin Core reference client written in C++ as well. Similarly to the ABC version, BU features an adjustable blocksize cap and other concepts like emergent consensus and Xthin blocks. Bitcoin Verde is a complete full node, block explorer and library built from the ground up. BCHD is an alternative full node bitcoin cash client written in Go (golang ... Ebenfalls ist es möglich sich den Kontostand einer Bitcoin Adresse in einem “Watching-only” Modus anzusehen, ohne dass der Computer mit dem Internet verbunden sein muss. Das Electrum Bitcoin Wallet ist verfügbar für: Windows XP, Windows Vista, Windows 7, Windows 8, Windows 10, OS X, Linux und darüber hinaus auch für Android Smartphones. Electrum Bitcoin Wallet. Impressum This website is hosted by Electrum Technologies GmbH Electrum Technologies was founded by Thomas Voegtlin in 2013. Its mission is to develop, package and distribute Electrum software, and to provide services to Bitcoin users and businesses.
This video is unavailable. Watch Queue Queue. Watch Queue Por meio de um comunicado oficial em seu site, a exchange anunciou a Binance Lending, que, segundo o post, estará disponível para os clientes a partir das 6:00 (UTC) da próxima quarta-feira, de ... This is a short video of me talking about my ASICminer USB Block Erupters on my Macbook Pro in OS X. They are plugged into a 9 port ANKER USB hub. Get an additional $10 in Bitcoins from Coinbase when purchasing through my referral link http://fredyen.com/get/Bitcoins Here is a quick beginner's guide on ... Step up your game and Check Out Binance too: https: ... it’s a lite client wallet, meaning you don’t have to download the entire blockchain, and it is compatible with Windows, Linux and OSX ... Get the Ledger Nano X to Safely store your Crypto - https://www.ledgerwallet.com/r/acd6 Help support the channel by joining my Patreon group - https://www.pa... No vídeo de hoje vamos analisar a plataforma de futuros da binance e analisar passo a passo como operar os contratos futuros do bitcoin na binance com tranquilidade. Para quem não sabe contratos ...