nix-hashlisted

# Nix Hash ## Hash Formats in Nix Nix uses several hash encodings: - **SRI** (`sha256-BASE64`) — The modern standard, used in `fetchFromGitHub`, `fetchurl`, etc. Format: `<algo>-<base64>` - **Hex / base16** (`84a5d14c...`) — The encoding most upstream projects publish - **Base32** (`020ay2q1...`) — Nix-specific legacy encoding; still printed by default by `nix-prefetch-url` SRI is the preferred format. Always use SRI hashes in new derivations. ## Flat vs NAR Hashes Which bytes get hashed depends on how the fetcher consumes the source: - Raw file bytes ("flat") — matches plain `fetchurl` (no `unpack = true`). Compute with `nix hash file`. - NAR serialisation of an unpacked tree — matches `fetchFromGitHub`, `fetchzip`, and any fetcher with `unpack = true`. Compute with `nix hash path`. Prefetch accordingly: without unpacking for plain `fetchurl`, with unpacking when the fetcher extracts the archive. Getting this wrong is the most common cause of hash mismatches. ## Common Commands ### Converting Hashes ```bash # Convert any hash to SRI (hex/base32 input auto-detected) nix hash to-sri --type sha256 <hash> # Convert SRI to hex nix hash to-base16 --type sha256 <sri-hash> ``` On upstream Nix ≥ 2.19 these conversions also exist as `nix hash convert --to sri|base16|base32 --hash-algo sha256 <hash>`. Lix does not provide `nix hash convert`. ### Computing Hashes ```bash # Raw bytes of a file (matches plain fetchurl); add --base16 for hex output nix hash file --type sha25