We present the Casper Network, a new Turing-complete smart-contract platform, backed by a Proof-of-Stake (PoS) consensus algorithm and WebAssembly (wasm). The network is a permissionless, decentralized, public blockchain. The consensus protocol is called Highway, and the complete paper is found in GitHub: https://github.com/CasperLabs/highway. The consensus protocol allows clients to use different confidence thresholds to convince themselves that a given block is finalized. This protocol is built on Vlad Zamfir’s correct-by-construction (CBC) Casper research.
Rust is the primary programming language for smart contracts on the Casper blockchain because of its good support for compilation to wasm. However, the platform does not make assumptions about the source language and supports libraries facilitating contract development in other programming languages having wasm as a compile target. Other essential features include an account permissions model that allows the recovery of lost keys and a permissions model to securely share state between accounts and contracts (without expensive cryptographic checks). We also provide discussions of the economics of our proof-of-stake implementation and our token policies.
Get started with smart contract development on the Casper blockchain in AssemblyScript or Rust
Run node infrastructure on the Casper Network
Understand the architecture of the Casper Network, including network communication, execution semantics, account management, block structure, global state, serialization, unforgeable references, and tokens
Conceptualize Casper’s economic activity by understanding consensus, runtime, ecosystem, and the macroeconomy
Participate in the protocol by staking CSPR tokens with a validator in the Casper Network
Explore key definitions in the context of the Casper Network
Find answers regarding the Casper Network, CasperLabs, and the CSPR token sale
By accepting this CasperLabs Tech Spec (this “Whitepaper”), each recipient
hereof acknowledges and agrees that is not authorised to, and may not, forward
or deliver this Whitepaper, electronically or otherwise, to any other person or
reproduce this Whitepaper in any manner whatsoever. Any forwarding, distribution
or reproduction of this Whitepaper in whole or in part is unauthorised. Failure
to comply with this directive may result in a violation of applicable laws of
any affected or involved jurisdiction.
Nothing in this Whitepaper constitutes an offer to sell, or a solicitation to
purchase, the tokens native to the Casper blockchain (“CSPR”). In any
event, were this Whitepaper to be deemed to be such an offer or solicitation, no
such offer or solicitation is intended or conveyed by this Whitepaper in any
jurisdiction where it is unlawful to do so, where such an offer or solicitation
would require a license or registration, or where such an offer or solicitation
is subject to restrictions. In particular, any CSPR to be issued have not been,
and, as of the date of issuance of this Whitepaper, are not intended to be,
registered under the securities or similar laws of any jurisdiction, whether or
not such jurisdiction considers the CSPR to be a security or similar instrument,
and specifically, have not been, and, as of the date of issuance of this
Whitepaper are not intended to be, registered under the U.S. Securities Act of
1933, as amended, or the securities laws of any state of the United States of
America or any other jurisdiction and may not be offered or sold in any
jurisdiction where to do so would constitute a violation of the relevant laws of
This Whitepaper constitutes neither a prospectus according to Art. 652a of the
Swiss Code of Obligations (the “CO”) or Art. 1156 CO nor a prospectus or
basic information sheet according to the Swiss Financial Services Act (the
“FinSA”) nor a listing prospectus nor a simplified prospectus according to
Art. 5 of the Swiss Collective Investment Schemes Act (the “CISA”) nor any
other prospectus according to CISA nor a prospectus under any other applicable
The CSPR are not expected to be instruments in an offer and sale which are
subject to the jurisdiction or oversight of the U.S. Securities Exchange
Commission (the “SEC”). In any event, however, CSPR have not been approved or
disapproved by, and are not expected to be approved or disapproved by, the SEC
nor by the securities regulatory authority of any state of the United States of
America or of any other jurisdiction, and neither the SEC nor any such
securities regulatory authority has passed, or is expected to pass, upon the
accuracy or adequacy of this Whitepaper.
The distribution of this Whitepaper and the purchase, holding, and/or disposal
of CSPR may be restricted by law in certain jurisdictions. Persons reading this
Whitepaper should inform themselves as to (i) the possible tax
consequences, (ii) the legal and regulatory requirements, and (iii) any foreign
exchange restrictions or exchange control requirements, which they might
encounter under the laws of the countries of their citizenship, residence or
domi-cile and which might be relevant to the purchase, holding or disposal
of CSPR. No action has been taken to authorise the distribution of this
Whitepaper in any jurisdiction in which such authorisation might be required.
No action has been or is intended to be taken by CasperLabs Networks AG and/or
any of its affiliates in any jurisdiction that would or is intended to, permit a
public sale or offering of any CSPR, or possession or distribution of this
Whitepaper (in preliminary, proof or final form) or any other sale, offering or
publicity material relating to the CSPR, in any country or jurisdiction where
action for that purpose is required. Each recipient of this Whitepaper is
reminded that it has received this Whitepaper on the basis that it is a person
into whose possession this Whitepaper may be lawfully delivered in accordance
with the laws of the jurisdiction in which it is located and/or bound and it may
not nor is it authorised to deliver this document, electronically or otherwise,
to any other person. If the recipient receives this document by e-mail, then its
use of this e-mail is at its own risk and it is the recipient’s responsibility
to take precautions to ensure that such e-mail is free from viruses and other
items of a destructive nature.
Preliminary Nature of this Whitepaper
This Whitepaper is a draft and the information set out herein is of a
preliminary nature. Consequently, neither CasperLabs Networks AG nor any of its
affiliates assumes any responsibility that the information set out herein is
final or correct and each of the foregoing disclaims, to the fullest extent
permitted by applicable law, any and all liability whether arising in tort,
contract or otherwise in respect of this Whitepaper. Neither this Whitepaper nor
anything contained herein shall form the basis of or be relied on in connection
with or act as an inducement to enter into any contract or commitment
whatsoever. Recipients should note that the final structuring of CSPR and the
Casper blockchain is subject to ongoing technical, legal, regulatory and tax
considerations and each is, therefore, subject to material changes. In
particular, neither the applicability nor the non-applicability of Swiss
financial market regulations on the CSPR sale has not been confirmed by the Swiss
Financial Market Supervisory Authority (“FINMA”). CasperLabs Networks AG
and all its affiliates reserve the right to not assist in the completion of the
software underlying CSPR and the CasperLabs blockchain, to not participate in the
issuance or creation of CSPR or to change the structure of CSPR and/or the
Casper blockchain for any reason, each at its sole discretion.
This Whitepaper includes “forward-looking statements”, which are all statements
other than statements of historical facts included in this Whitepaper. Words
like “believe”, “anticipate”, “expect”, “project”, “estimate”, “predict”,
“intend”, “target”, “assume”, “may”, “might”, “could”, “should”, “will” and
similar expressions are intended to identify such forward-looking statements.
Such forward-looking statements involve known and unknown risks, uncertainties
and other factors, which may cause the actual functionality, performance or
features of the Casper blockchain and/or CSPR to be materially different from
any future functionality, performance or features expressed or implied by such
forward-looking statements. Such forward-looking statements are based on
numerous assumptions regarding the CasperLabs Networks AG’s and/or any of its
affiliates’ present and future expectations regarding the development of the
Casper blockchain and the associated software.
These forward-looking statements speak only as of the date of this Whitepaper.
CasperLabs Networks AG and its affiliates expressly disclaim any obligation or
undertaking to release any updates of or revisions to any forward-looking
statement contained herein to reflect any change in CasperLabs Networks AG’s
and/or any of its affiliates’ expectations with regard thereto or any change in
events, conditions or circumstances on which any such statement is based.
Furthermore, by accepting this Whitepaper, the recipient of hereof (the
“Recipient”) acknowledges and agrees that it understands the inherent risks
associated with blockchain and distributed ledger technology, tokens and
cryptocurrencies in general and the CSPR in particular, including, but not
limited to, those outlined hereinafter.
Risks associated with CasperLabs Networks AG’s experience: the
Recipient is aware that CasperLabs Networks AG and its affiliates constitute a
start-up group of companies. Inability of such companies to manage their
affairs, including any failure to attract and retain appropriate personnel,
could affect the completion and functionality of the Casper blockchain.
Risks associated with CSPR relative value: the Recipient understands and
accepts that a purchaser of CSPR may experience financial losses relative to
other assets, including fiat currency and/or any other cryptocurrency (including
any cryptocurrency used to acquire CSPR). Potential purchasers and holders of CSPR
are urged to carefully review this Whitepaper and assess and understand the risk
factors relating to the CSPR and the Casper blockchain before acquiring CSPR
(when and if CSPR become available).
Risks associated with (intellectual) property rights: the Recipient
understands and accepts that, due to a lack of originality of the software and
to the immaterial character of the CSPR, there may be no title of ownership in
and to the intellectual property rights relating to CSPR.
Risks associated with blockchain: the Recipient understands and accepts
that the smart contract, the underlying software application and software
platform (i.e. the Casper blockchain) is still in an early development stage
and unproven. The Recipient understands and accepts that there is no warranty
that the process for creating the CSPR and/or the Casper blockchain will be
uninterrupted or error-free and acknowledges that there is an inherent risk that
the software could contain weaknesses, vulnerabilities or bugs causing, inter
alia, the complete loss of CSPR. The Recipient understands and accepts that,
after launch of the Casper blockchain, the smart contract and/or underlying
protocols and/or the Casper blockchain and/or any other software involved
may either delay and/or not execute a contribution due to the overall
contribution volume, mining attacks and/or similar events.
Risk of weaknesses in the field of cryptography: the Recipient
understands and accepts that cryptography is a technology that evolves
relatively fast over time. At the same time, methods and tools to decrypt,
access and/or manipulate data stored on a distributed ledger or blockchain are
highly likely to progress in parallel and in addition, new technological
developments such as quantum computers may pose as of now unpredictable risks to
the CSPR and the Casper blockchain that could increase the risk of theft or
loss of CSPR (if and when CSPR are created and/or issued).
Regulatory risks: the Recipient understands and accepts that it is
possible that certain jurisdictions will apply existing regulations on, or
introduce new regulations addressing, distributed ledger technology and/or
blockchain technology based applications, which may be contrary to the current
setup of the smart contract or the CasperLabs Networks AG project and which
may, inter alia, result in substantial modifications of the smart contract
and/or the CasperLabs Networks AG project, including its termination and the
loss of the CSPR, if and when created and/or issued, or entitlements to receive
CSPR, for the Recipient.
Risks associated with abandonment / lack of success: the Recipient
understands and accepts that the creation of the CSPR and the development of the
Casper blockchain as well as the CasperLabs Networks AG project may be
abandoned for a number of reasons, including lack of interest from the public,
lack of funding, lack of prospects (e.g. caused by competing projects) and
legal, tax or regulatory considerations. The Recipient therefore understands
that there is no assurance that, even if the CSPR/CasperLabs blockchain project
is partially or fully developed and launched, the Recipient will receive any
benefits through the CSPR held by it (if and when created and/or issued).
Risks associated with a loss of private key: the Recipient understands
and accepts that CSPR, if and when created and/or issued, will only be accessed
by using a wallet technically compatible with CSPR and with a combination of the
Recipient’s account information (address) and private key, seed or password. The
Recipient understands and accepts that if its private key or password gets lost
or stolen, the CSPR associated with the Recipient’s account (address) will be
unrecoverable and will be permanently lost.
Risks associated with wallets: the Recipient understands and accepts
that CasperLabs Networks AG or any of its affiliates, employees, partners or
advisors are in no way responsible for the wallet to which any CSPR are
transferred. The Recipient understands and agrees that it is solely responsible
for the access and security of its wallet, for any security breach of its wallet
and/or with any loss of CSPR resulting from its wallet service provider,
including any termination of the service by the wallet provider and/or
bankruptcy of the wallet provider.
Risks associated with theft/hacks: the Recipient understands and accepts
that the smart contract, the website, the underlying software application and
software platform (i.e. the Casper blockchain), during its development and
after its launch, may be exposed to attacks by hackers or other individuals that
could result in an inability to launch the Casper blockchain or the theft or
loss of CSPR. Any such event could also result in the loss of financial and other
support of the CasperLabs Networks AG project impacting the ability to develop
the CasperLabs Networks AG project and Casper blockchain.
Risks associated with mining attacks: the Recipient understands and
accepts that, as with other cryptocurrencies and tokens, if and when launched,
the Casper blockchain is susceptible to attacks relating to validators. Any
successful attack presents a risk to the smart contract, expected proper
execution and sequencing of transactions, and expected proper execution and
sequencing of contract computations.
Risks associated with a lack of consensus: the Recipient understands and
accepts that the network of validators will be ultimately in control of the
genesis block and future blocks and that there is no warranty or assurance that
the network of validators will perform their functions and reach proper
consensus and allocate the CSPR to the Recipient as proposed by any terms. The
Recipient further understands that a majority of the validators could agree at
any point to make changes to the software and/or smart contracts and to run the
new version of the software and/or smart contracts. Such a scenario could lead
to the CSPR losing intrinsic value.
Risks associated with liquidity of CSPR: the Recipient understands and
accepts that with regard to the CSPR, if and when created and/or issued, no
market liquidity may be guaranteed and that the value of CSPR relative to other
assets, including fiat currency and/or any other cryptocurrency (including any
cryptocurrency used to acquire CSPR) over time may experience extreme volatility
or depreciate in full (including to zero) resulting in loss that will be borne
exclusively by the Recipient.
Risks associated with forking: the Recipient understands and accepts
that hard and soft forks as well as similar events may, inter alia, lead to the
creation of new or competing tokens to the CSPR, adversely affect the
functionality, convertibility or transferability or result in a full or partial
loss of units or reduction (including reduction to zero) of value of the
Recipient’s CSPR (if and when created and/or issued).