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tokens: (Makarov 2012 ). This result holds for a wider range of realistic models, such as the Newtonian creep model developed by Ferraz-Mello ( 2015 ). The orbital eccentricity and average viscosity are the two crucial parameters defining these probabilities. The issue of dynamical stability and long-term survival of a tightly packed close-in system such as TRAPPIST-1 has already been discussed in the discovery paper by Gillon et al. ( 2017 ). A system with the observed set of parameters breaks up within a relatively short time in numerical N -body integrations. Fine-tuning of initial orbital parameters is required to find a long-term stable configuration within the observational uncertainties. This indicates that the multidimensional parameter space is shredded, with small islands of stable solutions separated by areas of instability. How can a real physical system of high complexity converge on a small island of stability among an infinite number of possible unstable configurations? The stability islands should be attractors, i.e., there should exist a regulatory force driving the system to one of such islands and damping small perturbations. Gillon et al. ( 2017 ) suggested that considerable tidal effects can provide the required stabilization. However, tidal forces act much too slowly even for such close planets, while the break-up of an unstable system happens well within 1 Myr. Even though tidal effects are important on the lifetime scale, we still have to explain how the system originally found a stable configuration. Tamayo et al. ( 2017 ) proposed that a convergent migration in a protoplanetary disk can be such a regulatory mechanism. Subject to dynamic friction in the disk, young planets migrate generally inward and toward smaller eccentricities. Still, something would halt this process when a planet reaches a stability niche, even before the disk dispersal. This may be possible when the stability niche is also associated with a certain mean-motion resonance (MMR), or better still, a system of MMRs with other planets, because an MMR is known to be an attractor. The surviving protoplanets end up in intricate patterns of near-commensurability (Terquem Papaloizou 2007 ), a class of N -body systems radically different from the solar system. Luger et al. ( 2017 ) find that the TRAPPIST-1 system represents a chain of MMRs, where each triplet of adjacent planets is locked in a three-body resonance. In this paper, we begin with testing a long-term stable configuration suggested by Quarles et al. ( 2017 ). We also test the system for chaos, using the siblings method in numerical integrations. The resulting orbital eccentricities for the seven planets, termed for brevity as TR1-1, TR1-2, ..., TR1-7 (instead of the traditional notation TRAPPIST-1 b , c , ..., h ), are used to estimate the likely spin–orbit end states of the planets, assuming an Earth-like rheology described by the Maxwell model. We show that not all of the planets are expected to