lamancha iv: the service shell

Nov 2019 – May 2020 · age 37–38

What it was

The server that stood around the young Adama language, written inside the incubator and moved out in one commit "to offload". It was a Netty WebSocket server that compiled a Hearts game at boot, ran the language server in the same process, and sent each connected player only their own privacy-filtered view of the game document. Around that core sat a fluent Java DSL for a developer site, cookie tokens signed with a home-made hash, a deployment config that could roll new game rules out to a percentage of tables, and a demo of three Raft peers in one JVM. About 3,700 lines. It served a single table of Hearts well enough for a Svelte client, and it did not compile once it left home.

Wins, for the age

• At thirty-seven, Jeff had the per-viewer projection working end to end: one living document, each player seeing only what the rules allowed. That model as the unit of state came a year ahead of Cloudflare Durable Objects (2020).
• Ran the language server and the game server in one process, so editor tooling and the live runtime could never disagree.
• Treated game rules like production code: a canary percentage and a metric name, so a new rule set would reach a fraction of tables first.
• Reached for Raft as the durability story after the earlier chain-replication design, testing the idea before committing to it.

What it taught

• A server is where a language's promises get tested. The projection held; the authentication and the store were placeholders, and placeholders are what remain.
• Do not invent token schemes, even for a devkit. The cookie carried its own secret beside its signature, so anyone could have minted one.
• Offloading is not deleting. Moving the shell out kept the compiler tests green and left 3,700 lines that no longer built.
• Small typos have large blast radii: one literal string where a variable belonged sent every connection to the same shared document, and one Hearts table hid it.

Genealogy

Ancestors: Lamancha II: the runtime, compiler and language server it wrapped. Descendants: Adama Caravan: the durability question Raft only started to answer. Adama Platform: the Netty WebSocket tier and hosting layer, done properly. Part of: Lamancha.

Epitaph

Here lies a server that trusted every cookie and gave everyone the same document. It still showed each primate at the table only their own hand, and that was the part worth keeping.