Context: Because it is viewed simply edge-on, the HH212 protostellar systemis an ideal laboratory for studying the interplay of infall, outflow, androtation in the earliest stages of low-mass star formation. Aims: We wish toexploit the unmatched combination of high angular resolution, high sensitivity,high-imaging fidelity, and spectral coverage provided by ALMA to shed light onthe complex kinematics of the innermost central regions of HH212. Methods: Wemapped the inner 10" (4500 AU) of the HH212 system at about 0.5 arcsecresolution in several molecular tracers and in the 850 $\mu$m dust continuumusing the ALMA interferometer in band 7 in the extended configuration of theEarly Science Cycle 0 operations. Results: Within a single ALMA spectralset-up, we simultaneously identify all the crucial ingredients known to beinvolved in the star formation recipe namely: (i) the fast, collimated bipolarSiO jet driven by the protostar, (ii) the large-scale swept-up CO outflow,(iii) the flattened rotating and infalling envelope, with bipolar cavitiescarved by the outflow (in C$^{17}$O(3--2)), and (iv) a rotating wide-angle flowthat fills the cavities and surrounding the axial jet (in C$^{34}$S(7--6)). Inaddition, the compact high-velocity C$^{17}$O emission ($\pm$ 1.9--3.5 kms$^{-1}$ from systemic) shows a velocity gradient along the equatorial planeconsistent with a rotating disk of about 0.2 arcsec = 90 AU around a $\simeq0.3 \pm 0.1 M_{\rm \odot}$ source. The rotating disk is possibly Keplerian.Conclusions: HH212 is the third Class 0 protostar with possible signatures of aKeplerian disk of radius $\geq 30 AU$. The warped geometry in our CS datasuggests that this large keplerian disk might result from misaligned magneticand rotation axes during the collapse phase. The wide-angle CS flow suggeststhat disk winds may be present in this source.
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