mir-backend-beamlisted

Make It Right (BEAM runtime tier). Erlang VM / BEAM reliability footguns shared across every BEAM-based backend (Phoenix, Nerves, Broadway, pure Erlang/OTP) — distinct from the generic backend gates and from any one framework's mechanics. Covers: let-it-crash + supervision tree design (restart strategies, max_restarts escalation, poison-message crash-loops and why a catch-all handle_info does NOT stop them), unbounded mailbox growth and real backpressure (a GenServer.call timeout does not shed load; GenStage/Broadway; OTP 28 priority messages are not backpressure), hot GenServer as a serial bottleneck and when to use ETS / :counters / :persistent_term instead, blocking handle_call timing out callers, per-process heap isolation and refc-binary retention, distributed Erlang hazards (netsplits, :global, pairwise ordering, :erpc), what Elixir's set-theoretic type checker does and does not catch, and VM-level security (binary_to_term, atom exhaustion, distribution cookie/EPMD, :os.cmd vs System.cmd, OTP TLS/term-d
anantbhandarkar/make-it-right · ★ 15 · API & Backend · score 81

Install: claude install-skill anantbhandarkar/make-it-right

# /mir-backend-beam · Make It Right (BEAM runtime) The middle tier. `mir-backend` decides **what is correct** (any language). The framework module (e.g. `mir-backend-beam-phoenix`) knows the **library's mechanics**. This tier owns what's true for **all BEAM backends because they run on the Erlang VM** — the process model, message-passing concurrency, and fault-tolerance primitives that Phoenix, Nerves, Broadway, and plain Erlang all inherit. **Runtime assumed:** Elixir 1.20 on OTP 27–29; syntax examples are Elixir, the notes hold for Erlang directly. Verified 13 Aug 2026: **Elixir 1.20.3** is the current stable line (1.21 is unreleased, in development on `main`); **OTP 29.0.5** (4 Aug 2026) is the current major, with **28.5.0.5** and **27.3.4.16** as maintained lines. Elixir 1.20 requires OTP 27+ and supports up to OTP 29; Elixir 1.19 required OTP 28.1+ to run on the OTP 28 line. If the project is on OTP 26 or older, that is a Gate 4 risk row — the July 2026 security batch below was not backported below 27.3.4.15. Load order: `mir-backend` → `mir-backend-beam` → `<framework module>`. ## The BEAM footguns AI walks into (framework-agnostic) ### 1. Let-it-crash + supervision — design the tree, don't rescue everything A crashed worker is restarted by its supervisor without taking down the rest of the system. AI undermines this by wrapping every operation in `try/rescue`, converting a clean crash into a swallowed error that leaves the process alive with invalid state. - **Le