In a large stockpot, heat the olive oil over medium heat and gently saute the onion, garlic, chickpeas, and tamari for about 5 minutes, until the onion starts to soften.
Add in the carrots, celery, thyme, 2 teaspoons of salt, a few grinds of black pepper, and 4 cups of water. Bring the water to a boil, then lower the heat and cover the pot with a lid. Let the soup simmer until the vegetables are tender, about 20 to 25 minutes.
While the soup is simmering, use a spiralizer to create "noodles" out of the zucchini. When the soup vegetables are tender, stir the zucchini noodles into the hot soup and stir briefly, about 1-2 more minutes, until the zucchini is wilted and tender.
Season with additional salt and pepper to taste, and serve warm. Leftover soup can be stored in an airtight container in the fridge for up to a week.
Instant Pot: If you'd prefer to make this in the Instant Pot, use the Sauté function to complete Step 1, then press the Cancel button to change settings. Add in the ingredients in Step 2, secure the lid and turn the pressure release to sealing. Cook on high pressure for 10 minutes then allow the pressure to naturally release for 10 minutes. Move the pressure release to venting to release any remaining steam pressure, then stir in the zucchini noodles and adjust the seasoning to taste. Serve warm.