Adding some diagnostic context and error message

[termi-official]

Partially addressing #79

[codecov-commenter]

Codecov Report

Merging #80 (685e9e2) into master (78f5796) will decrease coverage by 0.24%.
The diff coverage is 57.14%.

@@            Coverage Diff             @@
##           master      #80      +/-   ##
==========================================
- Coverage   91.50%   91.26%   -0.25%     
==========================================
  Files           7        7              
  Lines        2271     2277       +6     
==========================================
  Hits         2078     2078              
- Misses        193      199       +6     

Impacted Files	Coverage Δ
src/Interfaces.jl	90.56% <53.84%> (-0.38%)	⬇️
src/SequentialBackend.jl	98.30% <100.00%> (ø)

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