Over the past year, Rabbi Naftali and Dina Brawer have run a number of pop-up minyans every few weeks - an experimental Shabbat morning service in locations around London.
But now they are going into pop-up plus, holding High Holy Day services to launch their new enterprise, Mishkan, "a community beyond borders".
Instead of having a congregation tied to one neighbourhood, the Orthodox couple will have no fixed spiritual abode. Mishkan is the Hebrew name for the Tabernacle that accompanied the Israelites from place to place in their journey through the wilderness.
"Pop-up is a new interpretation of that," says Mrs Brawer. "The idea of creating a community around what people are passionate about is really important, rather than limiting yourself to the particular geography of where you happen to be or the particular denomination you're in or the group of friends you are with. What's beautiful is that it brings people together interested in the same thing, who would otherwise not meet."
Rabbi Brawer adds: "For many Jews, having a one-shop stop for their Judaism doesn't work. They move around, they flit about. They are more used to picking and choosing. We go out to where people are."
That is especially true of the institutionally shy generation of "millennials" - those born between 1980 and 2000.
The two study groups he has started meet in coffee bars. While some people are drawn to "sacred space" such as a synagogue, others find that intimidating, he observes. "By popping up in a café or bar and studying Torah in a public space, we are able to transform secular into sacred, which is a very Jewish concept. There is a kedusha, holiness, everywhere."
Apart from prayer and learning, the third plank is "sharing" - they will be supporting one charity for the homeless and another to support the education of underprivileged children.
Their High Holy Days will take place in a "big tent of meeting" in a venue in Borehamwood, Hertfordshire.
"If prayer in the average synagogue is an album, we are creating a playlist," Rabbi Brawer explains. "We're breaking the prayer into much smaller units and we are inviting people to come to a unit, or as many units as they want, or the whole thing."
Each unit will focus on a particular theme, which has been the hallmark of their Shabbat minyans. "The siddur is bursting with ideas but because it was composed over many years, you have layers and layers of meanings and perspectives," Rabbi Brawer says. "It is almost impossible to experience all of that in one Shabbat tefilah."
So they select from the liturgy in order to explore an individual topic in depth for each service, such as gratitude or joy. And they will incorporate elements such as poetry or meditation.
The initiative was motivated particularly by Mrs Brawer's own experiences of returning too often from a conventional synagogue service "feeling depleted rather than uplifted. I felt I needed something different, but we realised other people were in the same situation for various reasons".Mishkan, however, is intended to be "a model that augments rather than replaces" existing institutions - hence it will not be running services weekly.
And although she is the UK Ambassador of the Jewish Feminist Orthodox Alliance, services will not be egalitarian in the style of partnership minyans but "stick to a traditional Orthodox format".
They are trying to incubate other ideas, one being "Torah lab - providing an alternative to cheder which works for parents and children together," Mrs Brawer says.
On the Sunday between Rosh Hashanah and Yom Kippur, Mishkan plans to stage a musical tashlich (the ritual of casting-away sin) in a park.
Mrs Brawer is currently studying for ordination at Yeshivat Maharat, the women's seminary in New York, while Rabbi Brawer, a former minister of Borehamwood and Elstree United Synagogue, heads a consultancy, Spiritual Capital Foundation.
"We both started from a Chabad background but we have drunk from different wells," Mrs Brawer says. "We've studied and thought hard about the values that have shaped our Judaism."
They have already had inquiries about Mishkan from abroad. "We see this as being part of a new way of imagining vibrant Jewish life," Rabbi Brawer says.