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We report the archival discovery of Lyman-$\alpha$ emission from the brightultraviolet galaxy Y002 at $z=7.677$, spectroscopically confirmed by itsionized carbon [CII] 158$\mu$m emission line. The Ly$\alpha$ line is spatiallyassociated with the rest-frame UV stellar emission ($M_{\rm UV}$~-22, 2xbrighter than $M^\star_{\rm UV}$) and it appears offset from the peak of theextended [CII] emission at the current ~1" spatial resolution. We derive anestimate of the unobscured SFR(UV)=$(22\pm1)\,M_\odot$ yr$^{-1}$ and set anupper limit of SFR(IR)$<15\,M_\odot$ yr$^{-1}$ from the far-infrared wavelengthrange, which globally place Y002 on the SFR(UV+IR)-L([CII]) correlationobserved at lower redshifts. In terms of velocity, the peak of the Ly$\alpha$emission is redshifted by $\Delta v$(Ly$\alpha$)~500 km s$^{-1}$ from thesystemic redshift set by [CII] and a high-velocity tail extends to up to ~1000km s$^{-1}$. The velocity offset is up to ~3.5x higher than the averageestimate for similarly UV-bright emitters at z~6-7, which might suggest that weare witnessing the merging of two clumps. A combination of strong outflows andthe possible presence of an extended ionized bubble surrounding Y002 wouldlikely facilitate the escape of copious Ly$\alpha$ light, as indicated by thelarge equivalent width EW(Ly$\alpha$)=$24^{+5}_{-6}$ \r{A}. Assuming that [CII]traces the neutral hydrogen, we estimate a HI gas fraction of $M({\rmHI})/M_\star\gtrsim8$ for Y002 as a system and speculate that patches of highHI column densities could contribute to explain the observed spatial offsetsbetween Ly$\alpha$ and [CII] emitting regions. The low dust content, implied bythe non-detection of the far-infrared continuum emission at rest-frame ~160$\mu$m, would be sufficient to absorb any potential Ly$\alpha$ photons producedwithin the [CII] clump as a result of large HI column densities.

The archival discovery of a strong Lyman-$\alpha$ and [CII] emitter at z = 7.677