I asked r/cpp a simple question: what does “modern C++” actually mean? Eighty-odd comments later I had a lot of opinions, a couple of art history lectures, and a surprising amount of drinking-age math. What I didn’t get was an answer to the two questions I cared about most. How long until “modern C++” is just C++? And is C++ the only language that does this to itself?
So I’m going to answer them myself. Possibly wrong, but with total confidence, which is the C++ way.
What Reddit said
Nobody agreed on a version. The comments did sort themselves into camps, though, and the camps are great.
The art historians. Modern C++ means C++11 and later, forever. “Modern” is the name of a period, like modern art, which started in the 1860s and still hasn’t gotten old. This is a good argument. It also means C++ programmers have quietly become art critics. Picasso had his Blue Period. We had our Move Semantics Period.
The sliding window people. Modern means recent, so it’s C++20 now, maybe C++23. Also a good argument, with one small catch. A sliding window only works if your compiler slides with it, and the average corporate toolchain is somewhere at the back of the window, looking for its keys.
The “old enough to vote” crowd. A C++ feature doesn’t really get used until it’s old enough to vote. Or rent a car. Some teams hold out for drinking age. Meanwhile, people reported university courses still teaching C++98, and one commenter had a professor in the mid-2010s who had never heard of C++11. Modern C++ is fifteen years old, and a decent slice of the industry still treats it as a rumor.
The vibes school. It’s not a version at all. It’s whether you stopped managing memory by hand. By this definition you can write C++26 and still not be modern, as long as every pointer in your codebase is raw and every new is lonely.
The naming committee. Almost everyone agreed the old stuff is “legacy C++.” The trouble starts with what comes after modern. The thread offered postmodern, contemporary, Modern++, and avant-garde. Then someone asked if postmodern C++ would finally give us deconstructors, and I have nothing to add, because that’s the best joke in the thread.
Is C++ the only language with a “modern”?
I went in thinking yes. Nobody says modern Python. Nobody says modern TypeScript. Nobody says modern Scala.
Then I went looking, and the answer is no. But the list of languages that do say it is very funny.
Modern Fortran. There’s a standard reference book called Modern Fortran Explained.
Modern C. Also a book.
Modern JavaScript. There’s a popular tutorial site literally called The Modern JavaScript Tutorial.
Modern Java, which mostly means Java 8 and later.
Look at the first two. Fortran and C are standardized by ISO committees, same as C++. They’re our cousins. They’d sit at our table at Thanksgiving, if ISO had Thanksgiving. It has ballot periods instead.
Now look at the languages that never say it.
Python broke compatibility with Python 3, then officially killed Python 2 on January 1, 2020. There’s no “modern Python” because there’s no old Python left. There’s just a number.
Rust named its eras on purpose. They’re called editions (2015, 2018, 2021, 2024), and each project picks one.
Scala did the Python thing and called the new one Scala 3.
TypeScript is too young to have a past.
So here’s my theory. “Modern” is the word you reach for when you can’t throw the old version away and you refuse to give it a name. Python threw it away. Rust named it. C++ did neither, so every version of C++ ever shipped still lives inside the current one, and we need some word to point at the good parts.
Why C++ got it the worst
The gap. C++98 to C++11 was thirteen years. The new standard was supposed to ship in the 2000s, so its working name was C++0x. It shipped in 2011, at which point everyone agreed the x was hexadecimal. Thirteen years is long enough that the language you came back to wasn’t the one you left. Lambdas, move semantics, auto, smart pointers that actually work. Of course people needed a new word for it.
Fortran did the same thing. FORTRAN 77 came out in 1978. The next one was supposed to land in the 1980s, so it was called Fortran 8x. It shipped in 1991 as Fortran 90. That’s also thirteen years. Two ISO committees, two late releases, two “modern” eras. I’m not saying it’s a pattern. I’m saying it’s a pattern.
What’s in the box. Since 2011, C++ has shipped a new standard every three years. That’s slower than Python and JavaScript, which both ship every year, so the schedule alone isn’t the problem. A JavaScript release might add a handy new array method. Some C++ releases are like that too. The others add concepts, coroutines, ranges, modules, or reflection, any one of which changes how you’d write the whole program.
The silos. The version of C++ you write isn’t really your choice. It’s your compiler’s choice, then your employer’s, then your dependencies’. One team is on C++14 because of a vendor toolchain from 2017. Another is on C++20 but can’t use modules because the build system is still thinking about it. A third has reflection and won’t shut up about it. All of them are writing “C++,” and none of them can read each other’s code without a decoder ring.
Other languages found ways out. JavaScript has transpilers: you write the new stuff and a tool turns it into the old stuff for browsers that haven’t caught up. Python killed the old version. Rust has editions. C++ had a proposal for something like editions, called epochs, back in 2019. It didn’t go anywhere. So we have the silos, and we have “modern,” which is the word we use to point at the silo we wish we were in.
Designed by a treaty organization
This is the part I find genuinely delightful. Almost every popular language is designed by a company, a foundation, or one person with a mailing list. C++ is designed under ISO, the International Organization for Standardization. That’s the same organization that standardizes shipping containers and screw threads.
Features arrive as numbered papers with names like P2300R10, which is a proposal that has been revised ten times. The papers grind through study groups, working groups, and plenary votes, and the final ballot goes to national standards bodies. The committee meets in person a few times a year, occasionally in Kona, Hawaii, which I mention only for completeness. The official standard is a document you buy from Switzerland for a couple hundred francs. The drafts are free, everyone uses the drafts, and nobody talks about it.
JavaScript has a committee too, to be fair. But TC39 won’t finalize a feature until it’s shipping in two real implementations. WG21 is comfortable standardizing first and letting compiler vendors find out what it means later. This has gone about how you’d expect. C++98 standardized a feature called export templates. Exactly one compiler front end ever implemented it, and C++11 removed it. Part of the thirteen years spent making C++11 went into un-making C++98.
I say all this with love. I write papers for this committee. I am part of the problem. But you have to admit C++ is a bit of an anachronism. It’s a systems language for the 2020s, governed like it’s 1947.
So how long until it’s just C++?
Back to the question nobody answered.
Fortran gives us a clean data point. Fortran 90 started the modern Fortran era in 1991. It’s now 2026. That’s thirty-five years, and people still say “modern Fortran” with a straight face.
Modern C++ started in 2011. Add thirty-five years and you get 2046, as a lower bound. By then the committee will have shipped C++44, someone on Reddit will ask whether C++44 counts as postmodern, and the top answer will still be “C++11 and later.”
Until then I’ll keep saying “modern C++.” It’s tradition, and C++ never removes anything.
Use modern C++. Make no mistakes.