Technology Temple

Duetto — our C++ com­piler for the Web — is get­ting close to its first pub­lic release, due in a few days, and we would like to spend a few lines to present and explain our licens­ing model, as many peo­ple have been ask­ing recently.

When we started  work­ing on duetto around a year ago, we knew that we were going to release it as a FOSS project. We believe that duetto, by enabling truly seam­less client/server C++ pro­gram­ming, can become a corner-stone of Web appli­ca­tions and games devel­op­ment. But this can only hap­pen if an ecosys­tem of libraries, exten­sions and frame­works will be built around duetto itself. We know that the only way for this to hap­pen is to make the core of our tech­nol­ogy avail­able to every­one, for free. In addi­tion to that, since duetto is heav­ily based on the LLVM/clang frame­work and could not have existed oth­er­wise, we really feel that giv­ing back to the com­mu­nity is the most fair thing to do.

At the same time, we have also always been deter­mined to build a com­pany around this project. For this rea­son, we will be offer­ing a pre­mium pack­age that includes the same core FOSS tech­nol­ogy plus per­son­al­ized sup­port, pro­pri­etary friendly licens­ing and aux­il­iary perks includ­ing, but not lim­ited to, inte­gra­tion with devel­op­ment environments.

Let’s now talk licenses. The duetto com­piler itself is derived from LLVM and clang, both released under the Uni­ver­sity of Illinois/NCSA Open Source License. We are releas­ing our duetto com­piler under the same license, both to make it eas­ier for the com­mu­nity to con­tribute with code, to con­tribute back with some of our code to LLVM and clang, and because it does not make much sense to use a dual licens­ing scheme on a compiler.

In addi­tion to the com­piler, there are a bunch of head­ers and libraries which are essen­tials to develop using duetto. All those will be released under a clas­sic dual licens­ing scheme: GPLv2 for every­one and a pro­pri­etary non-copyleft license for pay­ing customers.

To sum­ma­rize, here is how duetto licens­ing will work:

• duetto core com­piler: Uni­ver­sity of Illinois/NCSA Open Source License (like the LLVM and clang projects)

• duetto core libraries/headers: dual license GPLv2; pro­pri­etary non-copyleft license avail­able for a fee

• duetto pre­mium fea­tures: pro­pri­etary and closed source, avail­able for a fee

We think this choice rep­re­sents a good bal­ance between being open and giv­ing back to the open source com­mu­nity, and build­ing a viable busi­ness model. We hope the open source com­mu­nity will appre­ci­ate our choice!

 Fol­low us on twit­ter @leaningtech and visit our web­site http://www.leaningtech.com to get updates on our upcom­ing release and for fur­ther information.

Duetto — our C++ com­piler for the Web — is get­ting close to its first pub­lic release, due in a few days, and we would like to spend a few lines to present and explain our licens­ing model, as many peo­ple have been ask­ing recently.

When we started  work­ing on duetto around a year ago, we knew that we were going to release it as a FOSS project. We believe that duetto, by enabling truly seam­less client/server C++ pro­gram­ming, can become a corner-stone of Web appli­ca­tions and games devel­op­ment. But this can only hap­pen if an ecosys­tem of libraries, exten­sions and frame­works will be built around duetto itself. We know that the only way for this to hap­pen is to make the core of our tech­nol­ogy avail­able to every­one, for free. In addi­tion to that, since duetto is heav­ily based on the LLVM/clang frame­work and could not have existed oth­er­wise, we really feel that giv­ing back to the com­mu­nity is the most fair thing to do.

At the same time, we have also always been deter­mined to build a com­pany around this project. For this rea­son, we will be offer­ing a pre­mium pack­age that includes the same core FOSS tech­nol­ogy plus per­son­al­ized sup­port, pro­pri­etary friendly licens­ing and aux­il­iary perks includ­ing, but not lim­ited to, inte­gra­tion with devel­op­ment environments.

Let’s now talk licenses. The duetto com­piler itself is derived from LLVM and clang, both released under the Uni­ver­sity of Illinois/NCSA Open Source License. We are releas­ing our duetto com­piler under the same license, both to make it eas­ier for the com­mu­nity to con­tribute with code, to con­tribute back with some of our code to LLVM and clang, and because it does not make much sense to use a dual licens­ing scheme on a compiler.

In addi­tion to the com­piler, there are a bunch of head­ers and libraries which are essen­tials to develop using duetto. All those will be released under a clas­sic dual licens­ing scheme: GPLv2 for every­one and a pro­pri­etary non-copyleft license for pay­ing customers.

To sum­ma­rize, here is how duetto licens­ing will work:

• duetto core com­piler: Uni­ver­sity of Illinois/NCSA Open Source License (like the LLVM and clang projects)

• duetto core libraries/headers: dual license GPLv2; pro­pri­etary non-copyleft license avail­able for a fee

• duetto pre­mium fea­tures: pro­pri­etary and closed source, avail­able for a fee

We think this choice rep­re­sents a good bal­ance between being open and giv­ing back to the open source com­mu­nity, and build­ing a viable busi­ness model. We hope the open source com­mu­nity will appre­ci­ate our choice!

 Fol­low us on twit­ter @leaningtech and visit our web­site http://www.leaningtech.com to get updates on our upcom­ing release and for fur­ther information.