[tkb]

For some data on the game size (based on my implementation and analysis of a BBC BASIC four-room game "MINI" which I referenced in another comment and won't self-promotionally spam again...)

The source code for MINI weighs in at 4.6 K, saved in the tokenised form used by BBC BASIC.

In comparison, the Inform 7 source is around 3.3K in size. But that isn’t executable - it can be run in Inform 7, or it can be compiled into a “story file”, of which Inform 7 supports two formats. In the older, more portable, Z-Code format, I got a blorb (package) of 406 K; in the newer, more sophisticated Glulx format, I got a blorb of 602 K.

And to actually play the story file, you need an interpreter - for example, Windows Glulxe, an interpreter for (as the observant reader might guess) playing Glulx story files under Windows, is a further 275 K. Inform 7 can also produce a story file and bundled Javascript interpreter for a version playable in a web browser: for MINI, this bundle weighs in at 1.1 MB.

[anthk]

For 8 bit computers I'd use Puny Inform. Much easier to develop and the resulting ZMachine V3 file will run everywere. Even on Game Boys and PostScript interpreters.