  $\require{mediawiki-texvc}$Given the sensitivity of the resonant
Lyman-$\mathrm{\alpha}$ (Ly$\mathrm{\alpha}$) transition to absorption by
neutral hydrogen, observations of Ly$\mathrm{\alpha}$ emitting galaxies (LAEs)
have been widely used to probe the ionising capabilities of reionisation-era
galaxies and their impact on the intergalactic medium (IGM). However, prior to
JWST our understanding of the contribution of fainter sources and of ionised
`bubbles' at earlier stages of reionisation remained uncertain. Here, we
present the characterisation of three exceptionally distant LAEs at $z>8$,
newly discovered by JWST/NIRSpec in the JADES survey. These three similarly
bright ($M_\text{UV} \approx -20\,\mathrm{mag}$) LAEs exhibit small
Ly$\mathrm{\alpha}$ velocity offsets from the systemic redshift, $\Delta
v_\mathrm{Ly\alpha} \lesssim 200\,\mathrm{km\,s^{-1}}$, yet span a range of
Ly$\mathrm{\alpha}$ equivalent widths ($15\,\AA$, $31\,\AA$, and $132\,\AA$).
The former two show moderate Ly$\mathrm{\alpha}$ escape fractions
($f_\mathrm{esc,Ly\alpha} \approx 10\%$), whereas Ly$\mathrm{\alpha}$ escapes
remarkably efficiently from the third ($f_\mathrm{esc,Ly\alpha} \approx 71\%$),
which moreover is very compact (half-light radius of $90\pm10\,\mathrm{pc}$).
We find these LAEs are low-mass galaxies dominated by very recent, vigorous
bursts of star formation accompanied by strong nebular emission from metal-poor
gas. We infer the two LAEs with modest $f_\mathrm{esc,Ly\alpha}$, one of which
reveals evidence for ionisation by an active galactic nucleus, may have
reasonably produced small ionised bubbles preventing complete IGM absorption of
Ly$\mathrm{\alpha}$. The third, however, requires a $\sim 3\,\text{physical
Mpc}$ bubble, indicating faint galaxies have contributed significantly. The
most distant LAEs thus continue to be powerful observational probes into the
earlier stages of reionisation.
