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  NCIP: 1
  Title: NCIP Purpose and Guidelines
  Author: Helder Garcia <>
  Comments-Summary: No comments yet.
  Comments-URI: Cash/NCIPs/wiki/Comments:NCIP-0001
  Status: Active
  Type: Process
  Created: 2018-02-14
  License: BSD-2-Clause

Table of Contents


A Niobio Cash Improvement Proposal (NCIP) is a design document providing information to the Niobio Cash community, or describing a new feature for Niobio Cash or its processes or environment. The NCIP should provide a concise technical specification of the feature and a rationale for the feature.

We intend NCIPs to be the primary mechanisms for proposing new features and for documenting the design decisions that have gone into Niobio Cash. The NCIP author is responsible for building consensus within the community and documenting dissenting opinions.

Because the NCIPs are maintained as text files in a versioned repository, their revision history is the historical record of the feature proposal.


This NCIP is dual-licensed under the Open Publication License and BSD 2-clause license.

This NCIP is a derived work from BIP-0002 (Bitcoin Improvement Proposal).

NCIP workflow

The NCIP process begins with a new idea for Niobio Cash. Each potential NCIP must have a champion -- someone who writes the NCIP using the style and format described below, shepherds the discussions in the appropriate forums, and attempts to build community consensus around the idea. The NCIP champion (a.k.a. Author) should first attempt to ascertain whether the idea is NCIP-able. Small enhancements or patches to a particular piece of software often don't require standardisation between multiple projects; these don't need a NCIP and should be injected into the relevant project-specific development workflow with a patch submission to the applicable issue tracker. The first step should be to search past discussions to see if an idea has been considered before, and if so, what issues arose in its progression. After investigating past work, the best way to proceed is by posting about the new idea to the Niobio Cash GitterRoom.

Vetting an idea publicly before going as far as writing a NCIP is meant to save both the potential author and the wider community time. Asking the Niobio Cash community first if an idea is original helps prevent too much time being spent on something that is guaranteed to be rejected based on prior discussions (searching the internet does not always do the trick). It also helps to make sure the idea is applicable to the entire community and not just the author. Just because an idea sounds good to the author does not mean it will work for most people in most areas where Niobio Cash is used.

Once the champion has asked the Niobio Cash community as to whether an idea has any chance of acceptance, a draft NCIP should be presented to the Niobio Cash GitterRoom. This gives the author a chance to flesh out the draft NCIP to make it properly formatted, of high quality, and to address additional concerns about the proposal. Following a discussion, the proposal should be submitted to the NCIP git repository as a pull request. This draft must be written in NCIP style as described below, and named with an alias such as "NCIP-johndoe" until the editor has assigned it a NCIP number (authors MUST NOT self-assign NCIP numbers).

NCIP authors are responsible for collecting community feedback on both the initial idea and the NCIP before submitting it for review. However, wherever possible, long open-ended discussions on public mailing lists should be avoided. Strategies to keep the discussions efficient include: setting up a separate SIG mailing list for the topic, having the NCIP author accept private comments in the early design phases, setting up a wiki page or git repository, etc. NCIP authors should use their discretion here.

It is highly recommended that a single NCIP contain a single key proposal or new idea. The more focused the NCIP, the more successful it tends to be. If in doubt, split your NCIP into several well-focused ones.

When the NCIP draft is complete, the NCIP editor will assign the NCIP a number, label it as Standards Track, Informational, or Process, and merge the pull request to the NCIPs git repository. The NCIP editor will not unreasonably reject a NCIP. Reasons for rejecting NCIPs include duplication of effort, disregard for formatting rules, being too unfocused or too broad, being technically unsound, not providing proper motivation or addressing backwards compatibility, or not in keeping with the Niobio Cash philosophy. For a NCIP to be accepted it must meet certain minimum criteria. It must be a clear and complete description of the proposed enhancement. The enhancement must represent a net improvement. The proposed implementation, if applicable, must be solid and must not complicate the protocol unduly.

The NCIP author may update the draft as necessary in the git repository. Updates to drafts should also be submitted by the author as pull requests.

Transferring NCIP Ownership

It occasionally becomes necessary to transfer ownership of NCIPs to a new champion. In general, we'd like to retain the original author as a co-author of the transferred NCIP, but that's really up to the original author. A good reason to transfer ownership is because the original author no longer has the time or interest in updating it or following through with the NCIP process, or has fallen off the face of the 'net (i.e. is unreachable or not responding to email). A bad reason to transfer ownership is because you don't agree with the direction of the NCIP. We try to build consensus around a NCIP, but if that's not possible, you can always submit a competing NCIP.

If you are interested in assuming ownership of a NCIP, send a message asking to take over, addressed to both the original author and the NCIP editor. If the original author doesn't respond to email in a timely manner, the NCIP editor will make a unilateral decision (it's not like such decisions can't be reversed :).

NCIP Editors

The current NCIP editor is Helder Garcia who can be contacted at

NCIP Editor Responsibilities & Workflow

Off-list NCIP-related correspondence should be sent (or CC'd) to

For each new NCIP that comes in an editor does the following:

  • Read the NCIP to check if it is ready: sound and complete. The ideas must make technical sense, even if they don't seem likely to be accepted.
  • The title should accurately describe the content.
  • The NCIP draft must have been sent to the Niobio Cash Gitter Room for discussion.
  • Motivation and backward compatibility (when applicable) must be addressed.
  • The defined Layer header must be correctly assigned for the given specification.
  • Licensing terms must be acceptable for NCIPs.
If the NCIP isn't ready, the editor will send it back to the author for revision, with specific instructions.

Once the NCIP is ready for the repository it should be submitted as a "pull request" to the NCIP git repository where it may get further feedback.

The NCIP editor will:

  • Assign a NCIP number in the pull request.
  • Merge the pull request when it is ready.
  • List the NCIP in README.mediawiki
The NCIP editors are intended to fulfill administrative and editorial responsibilities. The NCIP editors monitor NCIP changes, and update NCIP headers as appropriate.

NCIP format and structure


NCIPs should be written in mediawiki format.

Each NCIP should have the following parts:

  • Preamble -- Headers containing metadata about the NCIP (see below).
  • Abstract -- A short (~200 word) description of the technical issue being addressed.
  • Copyright -- The NCIP must be explicitly licensed under acceptable copyright terms (see below).
  • Specification -- The technical specification should describe the syntax and semantics of any new feature. The specification should be detailed enough to allow competing, interoperable implementations for any of the current Niobio Cash platforms.
  • Motivation -- The motivation is critical for NCIPs that want to change the Niobio Cash protocol. It should clearly explain why the existing protocol is inadequate to address the problem that the NCIP solves.
  • Rationale -- The rationale fleshes out the specification by describing what motivated the design and why particular design decisions were made. It should describe alternate designs that were considered and related work. The rationale should provide evidence of consensus within the community and discuss important objections or concerns raised during discussion.
  • Backwards compatibility -- All NCIPs that introduce backwards incompatibilities must include a section describing these incompatibilities and their severity. The NCIP must explain how the author proposes to deal with these incompatibilities.
  • Reference implementation -- The reference implementation must be completed before any NCIP is given status "Final", but it need not be completed before the NCIP is accepted. It is better to finish the specification and rationale first and reach consensus on it before writing code. The final implementation must include test code and documentation appropriate for the Niobio Cash protocol.

NCIP header preamble

Each NCIP must begin with an RFC 822 style header preamble. The headers must appear in the following order. Headers marked with "*" are optional and are described below. All other headers are required.

  NCIP: <NCIP number, or "?" before being assigned>
* Layer: <Consensus (upgrade) | Consensus (hard fork) | Peer Services | API/RPC | Applications>
  Title: <NCIP title; maximum 44 characters>
  Author: <list of authors' real names and email addrs>
* Discussions-To: <email address>
* Comments-Summary: <summary tone>
  Comments-URI: <links to wiki page for comments>
  Status: <Draft | Active | Proposed | Deferred | Rejected |
           Withdrawn | Final | Replaced | Obsolete>
  Type: <Standards Track | Informational | Process>
  Created: <date created on, in ISO 8601 (yyyy-mm-dd) format>
  License: <abbreviation for approved license(s)>
* License-Code: <abbreviation for code under different approved license(s)>
* Post-History: <dates of postings to Niobio Cash mailing list, or link to thread in mailing list archive>
* Requires: <NCIP number(s)>
* Replaces: <NCIP number>
* Superseded-By: <NCIP number>

The Layer header (only for Standards Track NCIPs) documents which layer of Niobio Cash the NCIP applies to. See NCIP 123 for definitions of the various NCIP layers. Activation of this NCIP implies activation of NCIP 123.

The Author header lists the names and email addresses of all the authors/owners of the NCIP. The format of the Author header value must be

  Random J. User <address@dom.ain>

If there are multiple authors, each should be on a separate line following RFC 2822 continuation line conventions.

While a NCIP is in private discussions (usually during the initial Draft phase), a Discussions-To header will indicate the mailing list or URL where the NCIP is being discussed. No Discussions-To header is necessary if the NCIP is being discussed privately with the author, or on the Niobio Cash email mailing lists.

The Type header specifies the type of NCIP: Standards Track, Informational, or Process.

The Created header records the date that the NCIP was assigned a number, while Post-History is used to record when new versions of the NCIP are posted to Niobio Cash mailing lists. Dates should be in yyyy-mm-dd format, e.g. 2001-08-14. Post-History is permitted to be a link to a specific thread in a mailing list archive.

NCIPs may have a Requires header, indicating the NCIP numbers that this NCIP depends on.

NCIPs may also have a Superseded-By header indicating that a NCIP has been rendered obsolete by a later document; the value is the number of the NCIP that replaces the current document. The newer NCIP must have a Replaces header containing the number of the NCIP that it rendered obsolete.

Auxiliary Files

NCIPs may include auxiliary files such as diagrams. Auxiliary files should be included in a subdirectory for that NCIP, or must be named NCIP-XXXX-Y.ext, where "XXXX" is the NCIP number, "Y" is a serial number (starting at 1), and "ext" is replaced by the actual file extension (e.g. "png").

NCIP types

There are three kinds of NCIP:

  • A Standards Track NCIP describes any change that affects most or all Niobio Cash implementations, such as a change to the network protocol, a change in block or transaction validity rules, or any change or addition that affects the interoperability of applications using Niobio Cash. Standards Track NCIPs consist of two parts, a design document and a reference implementation.
  • An Informational NCIP describes a Niobio Cash design issue, or provides general guidelines or information to the Niobio Cash community, but does not propose a new feature. Informational NCIPs do not necessarily represent a Niobio Cash community consensus or recommendation, so users and implementors are free to ignore Informational NCIPs or follow their advice.
  • A Process NCIP describes a process surrounding Niobio Cash, or proposes a change to (or an event in) a process. Process NCIPs are like Standards Track NCIPs but apply to areas other than the Niobio Cash protocol itself. They may propose an implementation, but not to Niobio Cash's codebase; they often require community consensus; unlike Informational NCIPs, they are more than recommendations, and users are typically not free to ignore them. Examples include procedures, guidelines, changes to the decision-making process, and changes to the tools or environment used in Niobio Cash development. Any meta-NCIP is also considered a Process NCIP.

NCIP status field


The typical paths of the status of NCIPs are as follows:

Champions of a NCIP may decide on their own to change the status between Draft, Deferred, or Withdrawn. The NCIP editor may also change the status to Deferred when no progress is being made on the NCIP.

A NCIP may only change status from Draft (or Rejected) to Proposed, when the author deems it is complete, has a working implementation (where applicable), and has community plans to progress it to the Final status.

NCIPs should be changed from Draft or Proposed status, to Rejected status, upon request by any person, if they have not made progress in three years. Such a NCIP may be changed to Draft status if the champion provides revisions that meaningfully address public criticism of the proposal, or to Proposed status if it meets the criteria required as described in the previous paragraph.

An Proposed NCIP may progress to Final only when specific criteria reflecting real-world adoption has occurred. This is different for each NCIP depending on the nature of its proposed changes, which will be expanded on below. Evaluation of this status change should be objectively verifiable, and/or be discussed on the development mailing list.

When a Final NCIP is no longer relevant, its status may be changed to Replaced or Obsolete (which is equivalent to Replaced). This change must also be objectively verifiable and/or discussed.

A process NCIP may change status from Draft to Active when it achieves rough consensus on the mailing list. Such a proposal is said to have rough consensus if it has been open to discussion on the development mailing list for at least one month, and no person maintains any unaddressed substantiated objections to it. Addressed or obstructive objections may be ignored/overruled by general agreement that they have been sufficiently addressed, but clear reasoning must be given in such circumstances.

Progression to Final status

A soft-fork NCIP strictly requires a clear miner majority expressed by blockchain voting (eg, using NCIP 9). In addition, if the economy seems willing to make a "no confidence" hard-fork (such as a change in proof-of-work algorithm), the soft-fork does not become Final for as long as such a hard-fork might have majority support, or at most three months. Soft-fork NCIPs may also set additional requirements for their adoption. Because of the possibility of changes to miner dynamics, especially in light of delegated voting (mining pools), it is highly recommended that a supermajority vote around 95% be required by the NCIP itself, unless rationale is given for a lower threshold.

A hard-fork NCIP requires adoption from the entire Niobio Cash economy, particularly including those selling desirable goods and services in exchange for Niobio Cash payments, as well as Niobio Cash holders who wish to spend or would spend their Niobio Cash (including selling for other currencies) differently in the event of such a hard-fork. Adoption must be expressed by de facto usage of the hard-fork in practice (ie, not merely expressing public support, although that is a good step to establish agreement before adoption of the NCIP). This economic adoption cannot be established merely by a super-majority, except by literally forcing the minority to accept the hard-fork (whether this is viable or not is outside the scope of this document).

Peer services NCIPs should be observed to be adopted by at least 1% of public listening nodes for one month.

API/RPC and application layer NCIPs must be implemented by at least two independent and compatible software applications.

Software authors are encouraged to publish summaries of what NCIPs their software supports to aid in verification of status changes. Good examples of this at the time of writing this NCIP, can be observed in Cash/Niobio Cash/blob/master/doc/ Niobio Cash Core's doc/ file as well as Cash-wallet/Niobio Cash-wallet/blob/master/wallet/ Niobio Cash Wallet for Android's wallet/ file.

These criteria are considered objective ways to observe the de facto adoption of the NCIP, and are not to be used as reasons to oppose or reject a NCIP. Should a NCIP become actually and unambiguously adopted despite not meeting the criteria outlined here, it should still be updated to Final status.


How is the entire Niobio Cash economy defined by people selling goods/services and holders?

  • For Niobio Cash to function as a currency, it must be accepted as payment. Niobio Cash have no value if you cannot acquire anything in exchange for them. If everyone accepting such payments requires a particular set of consensus rules, "Niobio Cash" are de facto defined by that set of rules - this is already the case today. If those consensus rules are expected to broaden (as with a hard-fork), those merchants need to accept payments made under the new set of rules, or they will reject "Niobio Cash" as invalid. Holders are relevant to the degree in that they choose the merchants they wish to spend their Niobio Cash with, and could also as a whole decide to sell under one set of consensus rules or the other, thus flooding the market with Niobio Cash and crashing the price.
Why aren't <x></x> included in the economy?

  • Some entities may, to some degree, also be involved in offering goods and/or services in exchange for Niobio Cash, thus in that capacity (but not their capacity as <x></x>) be involved in the economy.
  • Miners are not included in the economy, because they merely *rely on* others to sell/spend their otherwise-worthless mined produce. Therefore, they must accept everyone else's direction in deciding the consensus rules.
  • Exchanges are not included in the economy, because they merely provide services of connecting the merchants and users who wish to trade. Even if all exchanges were to defect from Niobio Cash, those merchants and users can always trade directly and/or establish their own exchanges.
  • Developers are not included in the economy, since they merely write code, and it is up to others to decide to use that code or not.
But they're doing something important and have invested a lot in Niobio Cash! Shouldn't they be included in such an important decision?

  • This NCIP does not aim to address what "should" be the basis of decisions. Such a statement, no matter how perfect in its justification, would be futile without some way to force others to use it. The NCIP process does not aim to be a kind of forceful "governance" of Niobio Cash, merely to provide a collaborative repository for proposing and providing information on standards, which people may voluntarily adopt or not. It can only hope to achieve accuracy in regard to the "Status" field by striving to reflect the reality of *how things actually are*, rather than *how they should be*.
What if a single merchant wishes to block a hard-fork?

  • This NCIP addresses only the progression of the NCIP Status field, not the deployment of the hard-fork (or any other change) itself.
  • Regardless, one shop cannot operate in a vacuum: if they are indeed alone, they will soon find themselves no longer selling in exchange for Niobio Cash payments, as nobody else would exist willing to use the previous blockchain to pay them. If they are no longer selling, they cease to meet the criteria herein which enables their veto.
How about a small number of merchants (maybe only two) who sell products to each other?

  • In this scenario, it would seem the previous Niobio Cash is alive any working, and that the hard-fork has failed. How to resolve such a split is outside the scope of this NCIP.
How can economic agreement veto a soft-fork?

  • The group of miners is determined by the consensus rules for the dynamic-membership multi-party signature (for Niobio Cash, the proof-of-work algorithm), which can be modified with a hard-fork. Thus, if the same conditions required to modify this group are met in opposition to a soft-fork, the miner majority supporting the soft-fork is effectively void because the economy can decide to replace them with another group of would-be miners who do not support the soft-fork.
What happens if the economy decides to hard-fork away from a controversial soft-fork, more than three months later?

  • The controversial soft-fork, in this circumstance, changes from Final to Replaced status to reflect the nature of the hard-fork replacing the previous (final) soft-fork.
What is the ideal percentage of listening nodes needed to adopt peer services proposals?

  • This is unknown, and set rather arbitrarily at this time. For a random selection of peers to have at least one other peer implementing the extension, 13% or more would be necessary, but nodes could continue to scan the network for such peers with perhaps some reasonable success. Furthermore, service bits exist to help identification upfront.
Why is it necessary for at least two software projects to release an implementation of API/RPC and application layer NCIPs, before they become Final?

  • If there is only one implementation of a specification, there is no other program for which a standard interface is used with or needed.
  • Even if there are only two projects rather than more, some standard coordination between them exists.
What if a NCIP is proposed that only makes sense for a single specific project?

  • The NCIP process exists for standardisation between independent projects. If something only affects one project, it should be done through that project's own internal processes, and never be proposed as a NCIP in the first place.

NCIP comments


Each NCIP should, in its preamble, link to a public wiki page with a summary tone of the comments on that page. Reviewers of the NCIP who consider themselves qualified, should post their own comments on this wiki page. The comments page should generally only be used to post final comments for a completed NCIP. If a NCIP is not yet completed, reviewers should instead post on the applicable development mailing list thread to allow the NCIP author(s) to address any concerns or problems pointed out by the review.

Some NCIPs receive exposure outside the development community prior to completion, and other NCIPs might not be completed at all. To avoid a situation where critical NCIP reviews may go unnoticed during this period, reviewers may, at their option, still post their review on the comments page, provided they first post it to the mailing list and plan to later remove or revise it as applicable based on the completed version. Such revisions should be made by editing the previous review and updating the timestamp. Reviews made prior to the complete version may be removed if they are no longer applicable and have not been updated in a timely manner (eg, within one month).

Pages must be named after the full NCIP number (eg, "NCIP 0001") and placed in the "Comments" namespace. For example, the link for NCIP 1 will be Cash/NCIPs/wiki/Comments:NCIP-0001 .

Comments posted to this wiki should use the following format:

    <Your opinion> --<Your name>, <Date of posting, as YYYY-MM-DD>

NCIPs may also choose to list a second forum for NCIP comments, in addition to the NCIPs wiki. In this case, the second forum's URI should be listed below the primary wiki's URI.

After some time, the NCIP itself may be updated with a summary tone of the comments. Summary tones may be chosen from the following, but this NCIP does not intend to cover all possible nuances and other summaries may be used as needed:

  • No comments yet.
  • Unanimously Recommended for implementation
  • Unanimously Discourage for implementation
  • Mostly Recommended for implementation, with some Discouragement
  • Mostly Discouraged for implementation, with some Recommendation
For example, the preamble to NCIP 1 might be updated to include the line:

    Comments-Summary: No comments yet.
    Comments-URI: Cash/NCIPs/wiki/Comments:NCIP-0001

These fields must follow the "Discussions-To" header defined in NCIP 1 (if that header is not present, it should follow the position where it would be present; generally this is immediately above the Status header).

To avoid doubt: comments and status are unrelated metrics to judge a NCIP, and neither should be directly influencing the other.


What is the purpose of NCIP comments?

  • Various NCIPs have been adopted (the criteria required for "Final" Status) despite being considered generally inadvisable. Some presently regard NCIPs as a "good idea" simply by virtue of them being assigned a NCIP number. Due to the low barrier of entry for submission of new NCIPs, it seems advisable for a way for reviewers to express their opinions on them in a way that is consumable to the public without needing to review the entire development discussion.
Will NCIP comments be censored or limited to particular participants/"experts"?

  • Participants should freely refrain from commenting outside of their area of knowledge or expertise. However, comments should not be censored, and participation should be open to the public.

NCIP licensing


New NCIPs may be accepted with the following licenses. Each new NCIP must identify at least one acceptable license in its preamble. The License header in the preamble must be placed after the Created header. Each license must be referenced by their respective abbreviation given below.

For example, a preamble might include the following License header:

    License: BSD-2-Clause

In this case, the NCIP text is fully licensed under both the OSI-approved BSD 2-clause license as well as the GNU All-Permissive License, and anyone may modify and redistribute the text provided they comply with the terms of *either* license. In other words, the license list is an "OR choice", not an "AND also" requirement.

It is also possible to license source code differently from the NCIP text. A optional License-Code header is placed after the License header. Again, each license must be referenced by their respective abbreviation given below.

For example, a preamble specifying the optional License-Code header might look like:

    License: BSD-2-Clause
    License-Code: GPL-2.0+

In this case, the code in the NCIP is not available under the BSD or All-Permissive licenses, but only under the terms of the GNU General Public License (GPL), version 2 or newer. If the code were to be available under *only* version 2 exactly, the "+" symbol should be removed from the license abbreviation. For a later version (eg, GPL 3.0), you would increase the version number (and retain or remove the "+" depending on intent).

    License-Code: GPL-2.0   # This refers to GPL v2.0 *only*, no later license versions are acceptable.
    License-Code: GPL-2.0+  # This refers to GPL v2.0 *or later*.
    License-Code: GPL-3.0   # This refers to GPL v3.0 *only*, no later license versions are acceptable.
    License-Code: GPL-3.0+  # This refers to GPL v3.0 *or later*.

In the event that the licensing for the text or code is too complicated to express with a simple list of alternatives, the list should instead be replaced with the single term "Complex". In all cases, details of the licensing terms must be provided in the Copyright section of the NCIP.

NCIPs are not required to be *exclusively* licensed under approved terms, and may also be licensed under unacceptable licenses *in addition to* at least one acceptable license. In this case, only the acceptable license(s) should be listed in the License and License-Code headers.

Recommended licenses

In addition, it is recommended that literal code included in the NCIP be dual-licensed under the same license terms as the project it modifies. For example, literal code intended for Niobio Cash Core would ideally be dual-licensed under the MIT license terms as well as one of the above with the rest of the NCIP text.

Not recommended, but acceptable licenses

Not acceptable licenses

All licenses not explicitly included in the above lists are not acceptable terms for a Niobio Cash Improvement Proposal unless a later NCIP extends this one to add them. However, NCIPs predating the acceptance of this NCIP were allowed under other terms, and should use these abbreviation when no other license is granted:


Why are there software licenses included?

  • Some NCIPs, especially consensus layer, may include literal code in the NCIP itself which may not be available under the exact license terms of the NCIP.
  • Despite this, not all software licenses would be acceptable for content included in NCIPs.
Why is Public Domain no longer acceptable for new NCIPs?

  • In some jurisdictions, public domain is not recognised as a legitimate legal action, leaving the NCIP simply copyrighted with no redistribution or modification allowed at all.