Migrating from v0.6 to v0.7

Migrating from v0.6 to v0.7

Executive summary

Chimera v0.7 is the first release in the new family that removes deprecated symbols rather than only adding to the surface. The two removals were prepped in earlier waves and have been emitting DeprecationWarning since v0.5, so the migration is mechanical:

Symbol removed	Replacement	Prepped in
AgentPreset.build()	CodingAgent.from_preset(...) (or AgentPreset._compose() for in-tree tests)	W12-10 (deprecation notice landed in v0.5)
chimera cc top-level subcommand alias	chimera mink	W13-E4 (stderr banner landed in v0.5)

Everything else in v0.7 is additive: a P2-batch of capability infill from the W12 audits (see the v0.7.0 release notes for the shipped list), and the usual quality-bar refresh.

The v0.5-era deprecations that already shipped a DeprecationWarning:

Symbol	Status in v0.7
chimera cc subcommand alias	Removed. argparse raises “unknown command” pointing at chimera mink.
AgentPreset.build()	Removed. Calling it raises AttributeError.
chimera.agents.presets.agent_styles module	Still exists; the AgentPreset class stays for in-tree tests of the legacy Agent + loop wiring. Use _compose() if you absolutely need it.
claude_code preset key	Still accepted as an alias for coding_agent with a DeprecationWarning; scheduled for removal in v0.8.

Breaking changes

1. AgentPreset.build() is gone

# Before (v0.6): emitted DeprecationWarning, still worked
from chimera.agents.presets.agent_styles import AgentPreset
agent = AgentPreset.SWE_AGENT.build(provider)

# After (v0.7): use CodingAgent.from_preset
from chimera.assembly.coding_agent import CodingAgent
agent = CodingAgent.from_preset("swebench", provider=provider)

CodingAgent.from_preset accepts provider= to keep your existing provider construction intact, or model="..." if you want it to build a provider for you.

If you need the exact lean profile that AgentPreset.build() used to return — bare Agent with no permissions, hooks, transcripts, content replacement, compaction, snapshot manager, or persistent memory — call AgentPreset._compose(provider) instead. It is the same code path the legacy build() delegated to (private now, but still supported for in-tree benchmark and test wiring).

See the agent-preset-to-coding-agent migration guide for the full preset-name map and behavior delta.

2. chimera cc subcommand is gone

# Before (v0.6): printed a stderr banner + DeprecationWarning, then ran mink
chimera cc -p "summarize this repo"

# After (v0.7): argparse "unknown command" — use chimera mink
chimera mink -p "summarize this repo"

If your scripts or CI still pinned chimera cc, replace it with chimera mink. The flag surface is identical — cc was never anything but a thin alias that called into the mink dispatcher.

The internal chimera mink cc subcommand (Mink’s own settings/cache helper) is unaffected; only the top-level alias goes.

What’s new in v0.7

The v0.7 release ships a curated P2 batch of capability infill picked from the W12 audits across Codex / OpenCode / Claw / Pi-Mono / Little-Coder gap analyses, plus the usual ProgramBench / scaffold maturation. See release notes for the per-item list with LOC + tests + docs cross-references.

Headlines:

• Items closing existing TODOs in the agent loop, tool layer, and per-CLI subcommand surfaces.
• Small UX wins on the seven-CLI surface (mink, otter, ferret, weasel, shrew, stoat, badger) that don’t need their own wave to ship.

The --legacy-react escape hatch remains for callers that want the old Session REPL.

Recommended upgrade path

1. Upgrade. pip install --upgrade chimera-run (or uv pip install --upgrade chimera-run). The PyPI distribution name is chimera-run; the Python import is still import chimera.
2. Sweep your code for AgentPreset.build().

   grep -rn "AgentPreset\..*\.build(" your_project/

   Replace each call site with CodingAgent.from_preset(...). The preset-name map is in agent-preset-to-coding-agent.md.
3. Sweep your CI / scripts for chimera cc.

   grep -rn "chimera cc\b" your_project/

   Replace each invocation with chimera mink.
4. chimera doctor — runs cleanly under v0.7 and reports 0.7.0 for each CLI’s version row. Catches API-key drift, optional daemons, extras, and stale pins.
5. Optionally adopt the W15 P2 items. None auto-launch without an opt-in surface (a flag, a file, or a tool registration) — see the release notes for the per-item adoption surface.

Per-CLI --version bumped to 0.7.0

Every animal CLI’s --version now prints chimera <name> 0.7.0. Scripts that pinned exact-string match against 0.6.0 need a one-line bump. Test fixtures inside the chimera repo were updated in this release; downstream user scripts may need a one-line change.

Deprecation timeline

Symbol	Status in v0.7	Removed in
chimera cc subcommand alias	Removed	v0.7.0
AgentPreset.build()	Removed	v0.7.0
claude_code preset key	DeprecationWarning (use coding_agent)	v0.8.0
chimera.agents.presets.agent_styles module	Stays (private _compose API)	not scheduled

See also

• Chimera 0.7.0 release notes — the full ship list and quality bar.
• Migrating from v0.5 to v0.6 — read first if you skipped v0.6.
• AgentPreset -> CodingAgent.from_preset — the canonical preset-migration recipe.
• Per-CLI quickstarts: mink · otter · ferret · weasel · shrew · stoat · badger.