# NevermindZZT/letter-shell

letter shell

Repository: https://github.com/NevermindZZT/letter-shell
Canonical: https://ross.abutalabs.com/products/letter-shell
Language: C
License: MIT
License Family: permissive
Last push: 2024-08-20T04:18:13+00:00

## Health v2 (maintenance only)
Score: 23/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 8, longevity 100
- inputs: {"age_days": 2965, "days_push": 743, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1884, forks 572 (observed 2026-08-28T04:05:48.876169+00:00)

## What it is
letter shell is an embeddable shell written in C for embedded devices, allowing command-line invocation of C functions within a running program. It supports command auto-completion, user and permission management, variables, and proxy function argument parsing.

## Use cases
- add a command-line shell to an embedded firmware
- call C functions in a running embedded program via serial console
- manage users and command permissions on an embedded device
- debug embedded hardware over UART with a shell
- run shell commands on a bare-metal microcontroller without an OS

## When to choose
- you need an interactive command shell in C on an MCU or RTOS
- you want function-level command invocation with auto-completion and permissions in resource-constrained devices

## When to avoid
- you need a full POSIX shell on a Linux system
- your project is not written in C or C-compatible code

## Facets
- artifact type: library
- maturity: stable
- function: cli, terminal-ui, developer-tools
- domain: embedded-systems, developer-tools
- platform: embedded, c, cross-platform
- tags: embedded-shell, command-line-interface, rtos, bare-metal, command-completion, user-management, command-line

## Member repositories
- NevermindZZT/letter-shell (main) score 23

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:05:48.876169+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T03:13:38.290192+00:00, confidence not recorded.
  - readme: https://github.com/NevermindZZT/letter-shell (fetched 2026-08-28T04:05:48.876169+00:00, sha f3cb2df551ce)
- Data as of 2026-08-30T08:39:29.467469+00:00.